Nakata Hiroki

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Profile and Settings

• Name (Japanese)

  Hiroki

• Name (Kana)

  Nakata

Research Interests

• 神経科学；運動制御；運動学習；発育発達; 生体医工学; ヘルスケア

Research Areas

• Life sciences, Biomedical engineering
• Life sciences, Neuroscience - general
• Life sciences, Nutrition and health science

Research Experience

• Apr. 2022, 9999, Nara Women's University
• Apr. 2021, Mar. 2022, 奈良女子大学 研究院工学系 准教授
• Apr. 2014, Mar. 2021, Nara Women's University, Faculty, Division of Human Life and Environmental Sciences
• Apr. 2013, Mar. 2014, 奈良女子大学 研究院人文科学系 准教授
• Oct. 2009, Mar. 2013, 早稲田大学スポーツ科学学術院 研究院助教
• Apr. 2009, Sep. 2009, 日本学術振興会 特別研究員(PD)（受入研究機関：東京大学大学院 総合文化研究科）
• Apr. 2007, Mar. 2009, 日本学術振興会 特別研究員(PD)（受入研究機関：名古屋大学医学部保健学科）
• Oct. 2006, Mar. 2007, 日本学術振興会 特別研究員(PD)（受入研究機関：自然科学研究機構 生理学研究所）

Education

• Sep. 2006, The Graduate University for Advanced Studies, Graduate School, Division of Life Science, 生理科学専攻
• Mar. 2001, University of Tsukuba, School of Health and Physical Education

Ⅱ．研究活動実績

Published Papers

• Adv Exerc Sports Physiol, The Athletes’ Brain., Nakata H, 2020, 26, 31, 34
• Refereed, J Hum Sport Exerc, The relationship between free-throw accuracy and performance variables in male wheelchair basketball players., Shigematsu S, Ogawa M, Neya M, Fujiwara M, Nakata H, 2022, 17, 919, 930, Scientific journal
• Refereed, Sports Med Open, Relative age effects in male Japanese professional athletes: A 25-year historical analysis., Sasano N, Katsumata Y, Nakata H, 2020, 6, 48
• Not Refereed, デサントスポーツ科学, 幼少期における筋出力調整能力の発達過程に関する研究, 大高千明、中田大貴、藤原素子, 2020, 41, 244, 251
• Refereed, Neurosci Lett, The relationship between cognitive style and sensory gating during auditory and somatosensory tasks., Mabuchi Y, Aoki Y, Shibasaki M, Nakata H, 2020, 738, 135354
• Refereed, スポーツ科学研究, 児童の接地タイプによる疾走パフォーマンスの違い, 信岡沙希重、樋口貴俊、後藤悠太、中田大貴、礒繁雄、彼末一之, 2020, 17, 28, 43
• Refereed, 奈良女子大学スポーツ科学研究, 奈良女子大学スポーツ健康科学コース, The relationship between continuous bilateral hop and basic exercise ability among young children, 室采音、高徳希、大高千明、藤原素子、中田大貴, Continuous bilateral hop has been used to evaluate a person's agility by focusing on the movement time. In the present study, we examined the movement time as well as hopping pattern score on continuous bilateral hop, and investigated the relationship between continuous bilateral hop and basic motor ability (25-m sprint, tennis ball throwing and standing long jumping) among 131 young children aged 4 to 5 years. The movement time was significantly shorter in 5- than in 4-year-old children, but the hopping pattern score did not change with increasing age. The score was significantly higher in girls than in boys, while the movement time was significantly shorter in boys than in girls. Moreover, a significant correlation was observed between the movement time and basic motor ability (25-m sprint and standing long jumping), the score and basic motor ability (25-m sprint, tennis ball throwing and standing long jumping). These data suggest that continuous bilateral hop can be used as indexes for agility as well motor coordination in young children., 2020, 22, 1, 12, 21

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• Refereed, Journal of sport rehabilitation, Comparison of the position-matching and position-reproducing tasks to detect deficits in knee position sense after reconstruction of the anterior cruciate ligament., Takuma Hoshiba; Hiroki Nakata; Yasuaki Saho; Kazuyuki Kanosue; Toru Fukubayashi, CONTEXT: Deficits in knee position sense following reconstruction of the anterior cruciate ligament (ACL) can delay an athlete's return to sport participation and increase the risk of reinjury. Deficits in position sense postreconstruction have been evaluated using either a position-reproducing or position-matching task. OBJECTIVE: The aim of our study was to combine both to determine which assessment would be more effective to identify deficits in knee position sense. DESIGN: Longitudinal laboratory-based study. PARTICIPANTS: Eleven athletes (6 men and 5 women; mean age, 20.5 [1.2] y), who had undergone ACL reconstruction with an ipsilateral hamstring autograft, and 12 age-matched controls. INTERVENTIONS: Position sense was evaluated at 6 and 12 months postreconstruction and once for the control group. In addition, peak isokinetic knee extension and flexion strength, at 60°/s and 180°/s, was assessed for the ACL reconstruction group to evaluate possible influences of muscle strength on knee joint position sense. MAIN OUTCOME MEASURES: The variables include the angular differences between the reference limb and indicator limb, and peak torque values of isokinetic knee extension and flexion. RESULTS: Significant matching differences were identified at 6 months postsurgery on the position-matching task, but not at 12 months postsurgery. No significant between-group and within-subject differences were identified on the position-reproducing task. No significant matching errors were identified for the control group. There was no correlation between errors in position sense and maximum isokinetic strength. CONCLUSION: The position-matching task is more sensitive than the position-reproducing task to identify deficits in knee position sense over the first year following ACL reconstruction surgery., 2020, 29, 1, 87, 92, Scientific journal, True, 10.1123/jsr.2017-0275

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• Not Refereed, 奈良女子大学スポーツ科学研究, 幼児の体力的特性と知能特性との関連についての検討：15年の推移に着目して, 中田大貴、室采音、土生川覚弥、大高千明、丹羽劭昭, 2019, 21, 1, 9
• Not Refereed, 日本生気象学会雑誌, 認知機能と環境ストレス, 中田大貴、芝﨑学, 2019, 56, 3, 11
• Refereed, NeuroReport, Ovid Technologies (Wolters Kluwer Health), Differences in characteristics of somatosensory evoked potentials between children and adults., Takezawa M, Kamijo K, Shibasaki M, Nakata H, 2019, 30, 18, 1284, 1288, Scientific journal, 10.1097/wnr.0000000000001355

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• Refereed, デサントスポーツ科学, 暑熱環境下の運動による脱水がヒト脳認知機能に及ぼす影響, Nakata Hiroki, 2019, 40, 47-57
• Refereed, 体育測定評価研究, 歓声量から観客を興奮させるプレーを評価する, Nakata Hiroki, 2019, 18, 71, 76
• Refereed, IBRO Reports, Assessment of brain mechanisms involved in the processes of thermal sensation, pleasantness/unpleasantness, and evaluation., Yuka Aizawa; Tokiko Harada; Hiroki Nakata; Mizuki Tsunakawa; Norihiro Sadato; Kei Nagashima, The conscious perception of thermal stimuli is divided into two categories: thermal sensation (i.e., discriminative component) and pleasantness/unpleasantness (i.e., hedonic component). There have been very few studies which clearly dissociated the two components. The aim of the present study was 1) to identify brain regions involved in perception of thermal stimuli per se, dissociating those related to the two components, and additionally 2) to examine brain regions of the explicit evaluation processes for the two components. Sixteen participants received local thermal stimuli of either 41.5 °C or 18.0 °C during whole-body thermal stimuli of 47.0 °C, 32.0 °C, or 17.0 °C. The local stimuli were delivered to the right forearm with the Peltier device. The whole-body stimuli delivered through a water-perfusion suit was aimed to modulate thermal pleasantness/unpleasantness to the local stimulus. The local stimulation at the same temperature was conducted five times with 30-s intervals. Brain activation was assessed by functional magnetic resonance imaging (fMRI), and the participants were asked to report their ratings of thermal sensation and pleasantness/unpleasantness following the cessation of each local stimulus. Local thermal stimulation activated specific brain regions such as the anterior cingulate cortex, insula, and inferior parietal lobe, irrespective of the temperature of local and whole-body stimuli; however, no specific activation for hot or cold sensation was observed. Different brain regions were associated with pleasantness and unpleasantness; the caudate nucleus and frontal regions for pleasantness, and the medial frontal and anterior cingulate cortex for unpleasantness. In addition, the explicit evaluation process for the discriminative and hedonic components immediately following the cessation of local stimulus involved different brain regions; the medial prefrontal cortex extending to the anterior cingulate cortex, insula, middle frontal cortex, and parietal lobes during the explicit evaluation of thermal sensation, and the medial prefrontal cortex, posterior cingulate cortex, and inferior parietal lobes during that of pleasantness/unpleasantness., 2019, 6, 54, 63, Scientific journal, True, 10.1016/j.ibror.2019.01.003

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• Refereed, J Phys Fitness Sports Med, Relationship between basketball free-throw accuracy and other performance variables among collegiate female players., Ogawa M, Hoshino S, Fujiwara M, Nakata H, 2019, 8, 127, 136
• Refereed, NeuroReport, Effects of white noise duration on somatosensory event-related potentials., Ohbayashi W, Kakigi R, Nakata H, 2019, 30, 26, 31
• Refereed, Neurosci Lett, Remote effects on corticospinal excitability during motor execution and motor imagery., Shironouchi F, Ohtaka C, Mizuguchi N, Kato K, Kakigi R, Nakata H, 2019, 707, 134284
• Refereed, Exp Brain Res, Effects of stimulus intensity and auditory white noise on human somatosensory cognitive processing: A study using event-related potentials., Mizukami H, Kakigi R, Nakata H, 2019, 237, 521, 530
• Refereed, Physiol Rep, Effects of repetitive exercise and thermal stress on human cognitive processing., Shibasaki M, Namba M, Kamijo YI, Ito T, Kakigi R, Nakata H, 2019, 7, e14003
• Refereed, PLoS One, The difference in hemodynamic responses between dominant and non-dominant hands during muscle contraction and relaxation: An fNIRS study., Yokoyama N, Ohtaka C, Kato K, Kubo H, Nakata H, The present study used functional near-infrared spectroscopy (fNIRS), and investigated the differences in neural activation of ipsi- or contralateral hemispheres between right dominant and left non-dominant hands among right-handed subjects using consecutive motor tasks with muscle contraction and relaxation. The subjects performed tasks under four conditions: (1) right hand up (R-Up), (2) left hand up (L-Up), (3) right hand down (R-Down), and (4) left hand down (L-Down). The peak amplitude of oxy-Hb was significantly larger at the contralateral than ipsilateral hemisphere in the premotor area (PM) under the R-Up condition, and no significant differences were observed between contra- and ipsilateral hemispheres under the L-Up condition. In addition, the peak amplitude was more negative at the contra- than ipsilateral hemisphere in the PM under the R-Down condition, while the peak amplitude was significantly more negative at the ipsi- than contralateral hemisphere in the PM under the L-Down condition. These results suggest that the PM of the left hemisphere among right-handed subjects plays an important role in muscle contraction and relaxation with force control., 2019, 14, 7, e0220100, Scientific journal, True, 10.1371/journal.pone.0220100

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• Refereed, PLoS One, Negative BOLD responses during hand and foot movements: An fMRI study., Nakata H, Domoto R, Mizuguchi N, Sakamoto K, Kanosue K, 2019, 14, e0215736
• Refereed, Am J Physiol Regul Integr Comp Physiol, Effects of whole-body skin cooling on human cognitive processing: A study using SEPs and ERPs., Nakata H, Kobayashi F, Lawley J, Kakigi R, Shibasaki M, 2019, 317, R432, R441
• Refereed, 奈良女子大学スポーツ科学研究, 認知スタイルとダーツパフォーマンスの関係性の検討, Nakata Hiroki, 2018, 20, 1-12
• Not Refereed, デサントスポーツ科学, 高体温時の認知機能低下の機能的磁気共鳴画像法による空間的神経ネットワーク評価, Nakata Hiroki, 2018, 39, 84-93
• Refereed, 陸上競技研究紀要, データベースを利用した新しい競技力指標と心理テストの関係性の検討, Nakata Hiroki, 2018, 14, 48-55
• Refereed, J Musculoskelet Neuronal Interact, Performance control in one consecutive motor task sequence - Approaching central neuronal motor behaviour preceding isometric contraction onsets and relaxation offsets at lower distinct torques., Vogt T, Kato K, Flüthmann N, Bloch O, Nakata H, Kanosue K, 2018, 18, 1, 8
• Refereed, J Appl Physiol, Dynamic cerebral autoregulation during cognitive task: Effect of hypoxia., Ogoh S, Nakata H, Miyamoto T, Bailey D, Shibasaki M, 2018, 124, 1413, 1419
• Refereed, PLoS One, Head-eye movement of collegiate baseball batters during fastball hitting., Higuchi T, Nagami T, Nakata H, Kanosue K, 2018, 13, e0200443
• Refereed, Neurosci Lett, Elsevier Ireland Ltd, Modulation of corticospinal excitability during positive and negative motor imageries., Yokota H, Mizuguchi N, Kakigi R, Nakata H, We investigated corticospinal excitability during positive (execution) and negative (suppression) imageries for the right and left upper and lower limbs. In the Positive Imagery tasks, sixteen subjects were instructed to repeatedly imagine rotation of the index finger of the right or left hand, or the ankle of the right or left foot. In the Negative Imagery tasks, they were asked to imagine the suppression of movements for the index finger of the right or left hand, or the ankle of the right or left foot. A single-pulse transcranial magnetic stimulation was delivered over the left hand primary motor cortex, and motor evoked potentials (MEPs) were recorded from the right first dorsal interosseous (FDI) muscle under all conditions. The MEP amplitudes of the FDI were significantly larger in the Positive and Negative Imagery tasks than in the resting control task during motor imagery of the right hand, left hand, and left foot, but not during that of right foot. Our results indicate that imageries of suppressing hand and foot movements enhanced corticospinal excitability., 2018, 672, 1, 5, Scientific journal, 10.1016/j.neulet.2018.02.036

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• Refereed, Sports Med Open, Characteristics of relative age effects and anthropometric data in Japanese recreational and elite male junior baseball players., Katsumata Y, Omuro K, Mitsukawa N, Nakata H, 2018, 4, 52
• Refereed, Eur J Pain, Wiley, Warm-, hot-, and pain-related neural activities depending on baseline skin temperatures., Nakata H, Kakigi R, Shibasaki M, 2018, 22, 10, 1791, 1799, Scientific journal, 10.1002/ejp.1275

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• Not Refereed, 奈良体育学会研究年報, 暑熱負荷時の認知機能評価, Nakata Hiroki, 2018, 22, 19-24
• Not Refereed, 奈良体育学会研究年報, ホワイトノイズがGo/No-go課題中の事象関連電位に及ぼす影響, Nakata Hiroki, 2018, 22, 13-18
• Not Refereed, 奈良体育学会研究年報, 高体温時および顔／頭部冷却時における体性感覚認知処理過程の検討, Nakata Hiroki, 2018, 22, 7-12
• Not Refereed, 奈良体育学会研究年報, 生まれつき足が遅い子はいない, Nakata Hiroki, 2018, 22, 45-46
• Refereed, Sci Rep, NATURE PUBLISHING GROUP, Suppression of cognitive function in hyperthermia; From the viewpoint of executive and inhibitive cognitive processing, Shibasaki M, Namba M, Oshiro M, Kakigi R, Nakata H, Climate change has had a widespread impact on humans and natural systems. Heat stroke is a life-threatening condition in severe environments. The execution or inhibition of decision making is critical for survival in a hot environment. We hypothesized that, even with mild heat stress, not only executive processing, but also inhibitory processing may be impaired, and investigated the effectiveness of body cooling approaches on these processes using the Go/No-go task with electroencephalographic event-related potentials. Passive heat stress increased esophageal temperature (Tes) by 1.30 +/- 0.24 degrees C and decreased cerebral perfusion and thermal comfort. Mild heat stress reduced the amplitudes of the Go-P300 component (i.e. execution) and No-go-P300 component (i.e. inhibition). Cerebral perfusion and thermal comfort recovered following face/head cooling, however, the amplitudes of the Go-P300 and No-go-P300 components remained reduced. During whole-body cooling, the amplitude of the Go-P300 component returned to the pre-heat baseline, whereas that of the No-go-P300 component remained reduced. These results suggest that local cooling of the face and head does not restore impaired cognitive processing during mild heat stress, and response inhibition remains impaired despite the return to normothermia., Mar. 2017, 7, 43528, Scientific journal, 10.1038/srep43528

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• Refereed, 奈良女子大学スポーツ科学研究, 確率共鳴と運動抑制に関連した脳活動特性, Nakata Hiroki, 2017, 19, 1-10
• Not Refereed, 繊維製品消費科学, 暑熱環境下における認知機能, Nakata Hiroki, 2017, 58, 50-54
• Not Refereed, デサントスポーツ科学, 暑熱環境の違いが運動時のヒト脳認知機能に及ぼす影響, Nakata Hiroki, 2017, 38, 17-27
• Refereed, NeuroReport, LIPPINCOTT WILLIAMS & WILKINS, The relationship between cognitive style and event-related potentials during auditory and somatosensory Go/No-go paradigms, Imanaka M, Kakigi R, Nakata H, Cognitive style including field dependence/independence (FDI) is an important factor affecting individual personalities. The present study aimed to clarify the relationship between cognitive styles and the characteristics of cognitive processing using event-related potentials. We used the Embedded-Figures Test to assess the cognitive styles [field dependence (FD), field independence (FI)] of the individuals, and individuals performed auditory and somatosensory Go/No-go paradigms. Participants were divided into two groups (FD and FI) on the basis of EFT scores. Reaction times during auditory Go/No-go paradigms were significantly earlier in the FI group than in the FD group, and response variabilities and omission errors were significantly smaller in the FI group than in the FD group. Go-P300 and No-go-P300 amplitudes were significantly larger in the FI group than in the FD group, suggesting that the FI group exhibited greater neural activity for response executive and inhibitory processing. No significant differences were observed in the amplitudes or latencies of auditory N100 and somatosensory N140 components between the FI and FD groups, suggesting that auditory-related and somatosensory-related neural activities were not related to FDI cognitive styles. Our results showed that FDI cognitive styles were related to neural activity for response executive and inhibitory processing., 2017, 28, 822, 827, Scientific journal, 10.1097/WNR.0000000000000833

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• Refereed, NeuroReport, LIPPINCOTT WILLIAMS & WILKINS, Effects of white noise on event-related potentials in somatosensory Go/No-go paradigms, Ohbayashi W, Kakigi R, Naklata H, Exposure to auditory white noise has been shown to facilitate human cognitive function. This phenomenon is termed stochastic resonance, and a moderate amount of auditory noise has been suggested to benefit individuals in hypodopaminergic states. The present study investigated the effects of white noise on the N140 and P300 components of event-related potentials in somatosensory Go/No-go paradigms. A Go or No-go stimulus was presented to the second or fifth digit of the left hand, respectively, at the same probability. Participants performed somatosensory Go/No-go paradigms while hearing three different white noise levels (45, 55, and 65dB conditions). The peak amplitudes of Go-P300 and No-go-P300 in ERP waveforms were significantly larger under 55dB than 45 and 65dB conditions. White noise did not affect the peak latency of N140 or P300, or the peak amplitude of N140. Behavioral data for the reaction time, SD of reaction time, and error rates showed the absence of an effect by white noise. This is the first event-related potential study to show that exposure to auditory white noise at 55dB enhanced the amplitude of P300 during Go/No-go paradigms, reflecting changes in the neural activation of response execution and inhibition processing., 2017, 28, 788, 792, Scientific journal, 10.1097/WNR.0000000000000821

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• Refereed, Neurosci Res, ELSEVIER IRELAND LTD, Effects of mastication on human somatosensory processing: A study using somatosensory-evoked potentials, Nakata H, Aoki M, Sakamoto K, The aim of the present study was to investigate the effects of mastication on somatosensory processing using somatosensory-evoked potentials (SEPs). Fourteen healthy subjects received a median nerve stimulation at the right wrist under two conditions: Mastication and Control. SEPs were recorded in five sessions for approximately seven minutes: Pre, Post 1, 2, 3, and 4. Subjects were asked to chew gum for five minutes after one session in Mastication. Control included the same five sessions. The amplitudes and latencies of P14, N20, P25, N35, P45, and N60 components at C3', frontal N30 component at Fz, and P100 and N140 components at Pz were analyzed. The amplitude of P45-N60 was significantly smaller at Post 1, 2, 3, and 4 than at Pre in Control, but not in Mastication. The latency of P25 was significantly longer at Post 2, 3, and 4 than at Pre in Control, but not in Mastication. The latency of P100 was significantly longer at Post 2 than at Pre in Control, but not in Mastication. These results suggest the significant effects of mastication on the neural activity of human somatosensory processing. (C) 2016 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved., 2017, 117, 28, 34, Scientific journal, 10.1016/j.neures.2016.12.002

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• Refereed, Am J Physiol Regul Integr Comp Physiol, AMER PHYSIOLOGICAL SOC, Effects of face/head and whole body cooling during passive heat stress on human somatosensory processing, Nakata H, Namba M, Kakigi R, Shibasaki M, We herein investigated the effects of face/head and whole body cooling during passive heat stress on human somatosensory processing recorded by somatosensory-evoked potentials (SEPs) at C4' and Fz electrodes. Fourteen healthy subjects received a median nerve stimulation at the left wrist. SEPs were recorded at normothermic baseline (Rest), when esophageal temperature had increased by similar to 1.2 degrees C (heat stress: HS) during passive heating, face/head cooling during passive heating (face/head cooling: FHC), and after HS (whole body cooling: WBC). The latencies and amplitudes of P14, N20, P25, N35, P45, and N60 at C4' and P14, N18, P22, and N30 at Fz were evaluated. Latency indicated speed of the subcortical and cortical somatosensory processing, while amplitude reflected the strength of neural activity. Blood flow in the internal and common carotid arteries (ICA and CCA, respectively) and psychological comfort were recorded in each session. Increases in esophageal temperature due to HS significantly decreased the amplitude of N60, psychological comfort, and ICA blood flow in the HS session, and also shortened the latencies of SEPs (all, P < 0.05). While esophageal temperature remained elevated, FHC recovered the peak amplitude of N60, psychological comfort, and ICA blood flow toward preheat baseline levels as well as WBC. However, the latencies of SEPs did not recover in the FHC and WBC sessions. These results suggest that impaired neural activity in cortical somatosensory processing during passive HS was recovered by FHC, whereas conduction velocity in the ascending somatosensory input was accelerated by increases in body temperature., 2017, 312, 6, R996, R1003, Scientific journal, 10.1152/ajpregu.00039.2017

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• Refereed, Sports Med Open, Relationship between the relative age effect and lengths of professional careers in male Japanese baseball players: a retrospective analysis., Nakata H, 2017, 3, 21
• Refereed, Percept Mot Skills, SAGE PUBLICATIONS INC, Relative Age Effect in Physical Fitness Among Elementary and Junior High School Students, Nakata H, Akido M, Naruse K, Fujiwara M, The present study investigated characteristics of the relative age effect (RAE) among a general sample of Japanese elementary and junior high school students. Japan applies a unique annual age-grouping by birthdates between April 1 and March 31 of the following year for sport and education. Anthropometric and physical fitness data were obtained from 3,610 Japanese students, including height, weight, the 50-m sprint, standing long jump, grip strength, bent-leg sit-ups, sit and reach, side steps, 20-m shuttle run, and ball throw. We examined RAE-related differences in these data using a one-way analysis of variance by comparing students with birthdates in the first (April-September) versus second (October-March of the following year) semesters. We observed a significant RAE for boys aged 7 to 15 years on both anthropometric and fitness data, but a significant RAE for girls was only evident for physical fitness tests among elementary school and not junior high school students. Thus, a significant RAE in anthropometry and physical fitness was evident in a general sample of school children, and there were RAE gender differences among adolescents., 2017, 124, 900, 911, Scientific journal, 10.1177/0031512517722284

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• Refereed, J Appl Physiol, AMER PHYSIOLOGICAL SOC, Effects of acute hypoxia on human cognitive processing: A study using ERPs and SEPs., Nakata H, Miyamoto T, Ogoh S, Kakigi R, Shibasaki M, Although hypoxia has the potential to impair the cognitive function, the effects of acute hypoxia on the high-order brain function (executive and/or inhibitory processing) and somatosensory ascending processing remain unknown. We tested the hypothesis that acute hypoxia impairs both motor executive and inhibitory processing and somatosensory ascending processing. Fifteen healthy subjects performed two sessions (sessions 1 and 2), consisting of electroencephalographic event-related potentials with somatosensory Go/No-go paradigms and somatosensory-evoked potentials (SEPs) under two conditions (hypoxia and normoxia) on different days. On 1 day, participants breathed room air in the first and second sessions of the experiment; on the other day, participants breathed room air in the first session, and 12% O-2 in the second session. Acute hypoxia reduced the peak amplitudes of Go-P300 and No-go-P300, and delayed the peak latency of Go-P300. However, no significant differences were observed in the peak amplitude or latency of N140, behavioral data, or the amplitudes and latencies of individual SEP components between the two conditions. These results suggest that acute hypoxia impaired neural activity in motor executive and inhibitory processing, and delayed higher cognitive processing for motor execution, whereas neural activity in somatosensory processing was not affected by acute hypoxia. NEW & NOTEWORTHY Hypoxia has the potential to impair the cognitive function, but the effects of acute hypoxia on the cognitive function remain debatable. We investigated the effects of acute hypoxia on human cognitive processing using electroencephalographic event-related potentials and somatosensory-evoked potentials. Acute normobaric hypoxia impaired neural activity in motor executive and inhibitory processing, but no significant differences were observed in neural activity in somatosensory processing., 2017, 123, 1246, 1255, Scientific journal, 10.1152/japplphysiol.00348.2017

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• Not Refereed, バイオメカニクス研究, 児童の走運動における調整力, Nakata Hiroki, 2017, 20, 177, 181
• Not Refereed, 教育システム研究, 保健体育科の教員養成における教育実践演習の実践報告 －模擬授業・討議がひらく可能性－, Nakata Hiroki, 2017, 別冊, 191-204
• Not Refereed, 奈良体育学会研究年報, 機能的磁気共鳴画像法を用いた運動遂行時・運動イメージ時におけるNegative BOLD反応, Nakata Hiroki, 2017, 21, 19-24
• Not Refereed, 陸上競技研究紀要, 日本人アスリートにおける相対年齢効果, Nakata Hiroki, 2017, 13, 9-18
• Refereed, Front Hum Neurosci, Muscle relaxation of the foot reduces corticospinal excitability of hand muscles and enhances intracortical inhibition., Kato K, Muraoka T, Mizuguchi N, Nakagawa K, Nakata H, Kanosue K, 2016, 10, 218
• Refereed, J Appl Biomech, Relation between lift force and ball spin for different baseball pitches., Nagami T, Higuchi T, Nakata H, Yanai T, Kanosue K, 2016, 32, 196, 204
• Refereed, PLOS ONE, PUBLIC LIBRARY SCIENCE, Contribution of visual information about ball trajectory to baseball hitting accuracy., Higuchi T, Nagami T, Nakata H, Isaka T, Kanosue K, The contribution of visual information about a pitched ball to the accuracy of baseball-bat contact may vary depending on the part of trajectory seen. The purpose of the present study was to examine the relationship between hitting accuracy and the segment of the trajectory of the flying ball that can be seen by the batter. Ten college baseball field players participated in the study. The systematic error and standardized variability of ball-bat contact on the bat coordinate system and pitcher-to-catcher direction when hitting a ball launched from a pitching machine were measured with or without visual occlusion and analyzed using analysis of variance. The visual occlusion timing included occlusion from 150 milliseconds (ms) after the ball release (R+150), occlusion from 150 ms before the expected arrival of the launched ball at the home plate (A-150), and a condition with no occlusion (NO). Twelve trials in each condition were performed using two ball speeds (31.9 m.s(-1) and 40.3 m.s(-1)). Visual occlusion did not affect the mean location of ball-bat contact in the bat's long axis, short axis, and pitcher-to-catcher directions. Although the magnitude of standardized variability was significantly smaller in the bat's short axis direction than in the bat's long axis and pitcher-to-catcher directions (p < 0.001), additional visible time from the R+150 condition to the A-150 and NO conditions resulted in a further decrease in standardized variability only in the bat's short axis direction (p < 0.05). The results suggested that there is directional specificity in the magnitude of standardized variability with different visible time. The present study also confirmed the limitation to visual information is the later part of the ball trajectory for improving hitting accuracy, which is likely due to visuo-motor delay., 2016, 11, e0148498, Scientific journal, 10.1371/journal.pone.0148498

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• Refereed, J Phys Fitness Sports Med, The Japanese Society of Physical Fitness and Sports Medicine, Anteroposterior ground reaction force as an indicator of gait alteration during treadmill walking after anterior cruciate ligament reconstruction., Hoshiba T, Nakata H, Saho Y, Kanosue K, Fukubayashi T, We investigated the weight transferring aspect of gait pattern during treadmill walking and muscle strength of the knee extensors and flexors following unilateral anterior cruciate ligament (ACL) reconstruction surgery. At 6 and 12 postoperative months, 11 patients (six men, five women) walked on a split-belt treadmill with two embedded force plates at their preferred speeds, 20% slower and 20% faster. Seventeen healthy control subjects (nine men, eight women) were also evaluated. Peak values of three components of ground reaction force (vertical, anteroposterior, and mediolateral) were measured bilaterally, and their variabilities were analyzed by coefficients of variation (CVs). The CVs for the anteroposterior forces differed between the reconstructed and contralateral limbs at 6 postoperative months, and this difference disappeared at 12 months. This was not matched by the time course change of quadriceps strength since quadriceps weakness in the reconstructed limb persisted up to 12 months postoperative. These findings suggest that gait alteration in anteroposterior forces may not be caused by quadriceps weakness alone, and the reconstructed and contralateral limbs may compensate for gait execution over the first year following ACL reconstruction surgery., 2016, 5, 1, 95, 103, 10.7600/jpfsm.5.95

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• Refereed, Neuroscience, PERGAMON-ELSEVIER SCIENCE LTD, Motor imagery beyond the motor repertoire: Activity in the primary visual cortex during kinesthetic motor imagery of difficult whole body movements., Mizuguchi N, Nakata H, Kanosue K, To elucidate the neural substrate associated with capabilities for kinesthetic motor imagery of difficult wholebody movements, we measured brain activity during a trial involving both kinesthetic motor imagery and action observation as well as during a trial with action observation alone. Brain activity was assessed with functional magnetic resonance imaging (fMRI). Nineteen participants imagined three types of whole-body movements with the horizontal bar: the giant swing, kip, and chin-up during action observation. No participant had previously tried to perform the giant swing. The vividness of kinesthetic motor imagery as assessed by questionnaire was highest for the chin-up, less for the kip and lowest for the giant swing. Activity in the primary visual cortex (V1) during kinesthetic motor imagery with action observation minus that during action observation alone was significantly greater in the giant swing condition than in the chin-up condition within participants. Across participants, V1 activity of kinesthetic motor imagery of the kip during action observation minus that during action observation alone was negatively correlated with vividness of the kip imagery. These results suggest that activity in V1 is dependent upon the capability of kinesthetic motor imagery for difficult whole-body movements. Since V1 activity is likely related to the creation of a visual image, we speculate that visual motor imagery is recruited unintentionally for the less vivid kinesthetic motor imagery of difficult whole-body movements. (C) 2015 The Authors. Published by Elsevier Ltd. on behalf of IBRO. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)., 2016, 315, 104, 113, Scientific journal, 10.1016/j.neuroscience.2015.12.013

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• Refereed, 奈良女子大学スポーツ科学研究, 奈良女子大学生活環境学部スポーツ健康科学コース, Negative BOLD responses during motor execution and imagery: an fMRI study., Nakata H, Matsuda N, Mizuguchi N, Sakamoto K, Kanosue K, The aim of this functional magnetic resonance imaging (fMRI) study was to evaluate negative deflections in blood oxygen level-dependent (BOLD) signals during motor execution of left or right hand movements, and motor imagery of left or right hand movements. We observed the Negative BOLD responses during left and right hand movements in the superior frontal gyrus (SFG), medial frontal gurus (MFG), precuneus, ipsilateral primary motor cortex (MI), premotor area (PM), dorsolateral prefrontal cortex (DLPFC), and middle occipital gyrus (MOG), while those of Negative BOLD during motor imagery of left and right hand movements were found in the SFG/MFG and precuneus. These findings indicate that the SFG/MFG and precuneus, which involved regions similar to those of the default mode network, were involved in the neural networks of Negative BOLD during both motor execution and motor imagery. Also, deactivations in the ipsilateral MI, PM, DLPFC, and MOG during motor execution were added to the default neural networks. The present findings extend the applicability of BOLD signals by comparing Negative and Positive signals in order to understand the brain functions involved in motor execution and motor imagery., 2016, 18, 65, 77

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• Refereed, J Psychophysiology, HOGREFE & HUBER PUBLISHERS, Modality difference in N2 and P3 components between visual and auditory Go/No-go paradigms., Nakata H, Arakawa N, Suzuki C, Nakayama M, We investigated the modality difference in the N2 and P3 components of event-related potentials (ERPs) between visual and auditory Go/No-go paradigms. We evaluated the relationship between RT and the amplitudes and latencies of N2 and P3 in visual and auditory Go/No-go paradigms. No significant differences were observed in the latencies of N2 and P3 between visual and auditory paradigms. Significant correlations were observed between RT and the latency of P3 in the visual and auditory paradigms. In contrast, the amplitudes of N2 and P3 were significantly larger in the visual paradigm than in the auditory paradigm. A significant correlation was observed between RT and the amplitude of P3 only in the auditory paradigm. These results suggested that there were two neural networks for the response execution and inhibitory function, common and uncommon, that depended on the stimulus modality., 2016, 30, 131, 140, Scientific journal, 10.1027/0269-8803/a000163

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• Refereed, Am J Physiol Regul Integr Comp Physiol, AMER PHYSIOLOGICAL SOC, The effect of elevations in internal temperature on event-related potentials during a simple cognitive task in humans., Shibasaki M, Namba M, Oshiro M, Crandall C, Nakata H, The effect of hyperthermia on cognitive function remains equivocal, perhaps because of methodological discrepancy. Using electroencephalographic event-related potentials (ERPs), we tested the hypothesis that a passive heat stress impairs cognitive processing. Thirteen volunteers performed repeated auditory oddball paradigms under two thermal conditions, normothermic time control and heat stress, on different days. For the heat stress trial, these paradigms were performed at preheat stress (i.e., normothermic) baseline, when esophageal temperature had increased by similar to 0.8 degrees C, when esophageal temperature had increased by similar to 2.0 degrees C, and during cooling following the heat stress. The reaction time and ERPs were recorded in each session. For the time control trial, subjects performed the auditory oddball paradigms at approximately the same time interval as they did in the heat stress trial. The peak latency and amplitude of an indicator of auditory processing (N100) were not altered regardless of thermal conditions. An indicator of stimulus classification/evaluation time (latency of P300) and the reaction time were shortened during heat stress; moreover an indicator of cognitive processing (the amplitude of P300) was significantly reduced during severe heat stress (8.3 +/- 1.3 mu V) relative to the baseline (12.2 +/- 1.0 mu V, P < 0.01). No changes in these indexes occurred during the time control trial. During subsequent whole body cooling, the amplitude of P300 remained reduced, and the reaction time and latency of P300 remained shortened. These results suggest that excessive elevations in internal temperature reduce cognitive processing but promote classification time., 2016, 311, R33, R38, Scientific journal, 10.1152/ajpregu.00086.2016

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• Refereed, Am J Physiol Regul Integr Comp Physiol, AMER PHYSIOLOGICAL SOC, Effects of aerobic exercise under different thermal conditions on human somatosensory processing., Nakata H, Oshiro M, Namba M, Shibasaki M, The present study aimed to investigate the effects of aerobic exercise on human somatosensory processing recorded by somatosensory evoked potentials (SEPs) under temperate [TEMP, 20 degrees C and 40% relative humidity (RH)] and hot (HOT, 35 degrees C and 30% RH) environments. Fifteen healthy subjects performed 4 x 15-min bouts of a moderate cycling exercise [mean power output: 156.5 x 7.7 (SE) W], with a 10-min rest period and received a posterior tibial nerve stimulation at the left ankle before and after each exercise bout; SEPs were recorded in five sessions; 1st (pre), 2nd (post-1st exercise bout), 3rd (post-2nd exercise bout), 4th (post-3rd exercise bout), and 5th (post-4th exercise bout). The peak latencies and amplitudes of the P37, N50, P60, and N70 components at Cz were evaluated. The latencies of P37, N50, P60, and N70 were significantly shorter with the repetition of aerobic exercise, and these shortened latencies were significantly greater in the HOT condition than in the TEMP condition (P37: 3rd, P < 0.05, and 5th, P < 0.01; P60: 4th, P < 0.05, and 5th, P < 0.01; N70: 4th, P < 0.05, and 5th, P < 0.001). No significant differences were observed in the amplitudes of any SEP component under either thermal condition. These results suggest that the conduction velocity of the ascending somatosensory input was accelerated by increases in body temperature, and aerobic exercise did not alter the strength of neural activity in cortical somatosensory processing., 2016, 311, R629, R636, Scientific journal, 10.1152/ajpregu.00153.2016

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• Not Refereed, デサントスポーツ科学, 暑熱環境下における聴覚情報処理および高次認知機能の評価, Nakata Hiroki, 2016, 37, 82-91
• Refereed, Sci Rep, NATURE PUBLISHING GROUP, The right temporoparietal junction encodes efforts of others during action observation., Mizuguchi N, Nakata H, Kanosue K, Smooth social interactions require a deep understanding of others' intentions and feelings. In the present study, to investigate brain regions that respond to inference of others' effort level, we recorded brain activity during action observation of different effort levels using functional magnetic resonance imaging (fMRI). We used a dumbbell curl movement to depict a movement requiring effort. To dissociate the factors of effort level of the actor and weight of the dumbbell, we used four combinations of dumbbell weight and actor physique: a thin actor or a built actor lifting a heavy or light dumbbell. During observation of dumbbell curls, the bilateral front-parietal action observation network (AON) was activated. This included the premotor cortices, parietal cortices, visual areas 5/superior temporal cortices (STS), amygdalae, hippocampi, right dorsolateral and ventrolateral frontal cortices. When we evaluated brain regions associated with the actor's effort level, activity in the right temporoparietal junction (TPJ) and STS was observed. However, activity in the front-parietal AON was independent of the actor's effort during action observation. This finding suggests that the right TPJ and STS play an important role in the inference of others' effort levels during the observation of others' movements., 2016, 6, 30274, Scientific journal, 10.1038/srep30274

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• Not Refereed, Adv Exerc Sports Physiol, Japan Society of Exercise and Sports Physiology, Effects of voluntary movements on pain-related brain activity., Nakata H, Kakigi R, 2016, 22, 3, 39, 44

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• Refereed, 体育学研究, 児童の疾走速度とピッチ・ストライド・接地時間・滞空時間の関係, Nakata Hiroki, 2015, 60, 497-510
• Refereed, PLoS One, Skill-specific changes in somatosensory Nogo potentials in baseball players., Yamashiro K, Sato D, Onishi H, Sugawara K, Nakazawa S, Akatsuka K, Nakata H, Maruyama A, 2015, 10, e0142581
• Refereed, Front Psychol, The effect of somatosensory input on motor imagery depends upon motor imagery capability., Mizuguchi N, Yamagishi T, Nakata H, Kanosue K, 2015, 6, 104
• Refereed, Clin Neurophysiol, ELSEVIER IRELAND LTD, Mastication accelerates Go/No-go decisional processing: An event-related potential study., Sakamoto K, Nakata H, Yumoto M, Sadato N, Kakigi R, Objective: The purpose of the present study was to investigate the effect of mastication on Go/No-go decisional processing using event-related potentials (ERPs). Method: Thirteen normal subjects underwent seven sessions of a somatosensory Go/No-go paradigm for approximately 4 min; Pre, and Post 1, 2, 3, 4, 5, and 6. The Control condition included the same seven sessions. The RT and standard deviation were recorded, and the peak amplitude and latency of the N140 and P300 components were analyzed. Results: The RT was significantly shorter in Mastication than in Control at Post 1-3 and 4-6. The peak latency of N140 was earlier in Mastication than in Control at Post 4-6. The latency of N140 was shortened by repeated sessions in Mastication, but not by those in Control. The peak latency of P300 was significantly shorter in Mastication than in Control at Post 4-6. The peak latency of P300 was significantly longer in Control with repeated sessions, but not in Mastication. Conclusions: These results suggest that mastication may influence response execution processing in Go trials, as well as response inhibition processing in No-go trials. Significance: Mastication accelerated Go/No-go decisional processing in the human brain. (C) 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., 2015, 126, 2099, 2107, Scientific journal, 10.1016/j.clinph.2014.12.034

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• Refereed, 奈良女子大学スポーツ科学研究, 奈良女子大学生活環境学部スポーツ健康科学コース, Is relative age associated with sport dropout?: Evidence from Japanese novelists, Nakata H, Sakamoto K, The present study investigated the existence of the relative age effect, a biased distributionof birth dates, in Japanese novelists. The relative age effect is considered to be a factor forsuccess in sporting activities, with relatively older players in the same age group being morelikely to achieve sporting success than younger players. We hypothesized that relativelyyounger people were more likely to focus on other things besides sporting success, such astheir work, study, obtaining licentiates, and hobbies, than relatively older people. Astatistically biased distribution was observed in birth dates among novelists born in the1940s and onward, and the percentage of relatively younger people that were winners of theAkutagawa Prize or Naoki Prize, prestigious Japanese literary awards, was significantlyhigher than relatively older people. These results suggest that relatively younger peopleshifted their interest from succeeding in sport to something else, and relative age effectslasted in both childhood and adults., 2015, 17, 21, 29

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• Not Refereed, 日本運動器疼痛学会誌, 運動による除痛効果に関する脳内認知機構, Nakata Hiroki, 2015, 7, 132-138
• Refereed, Neurosci Lett, ELSEVIER IRELAND LTD, Effects of task repetition on event-related potentials in somatosensory Go/No-go paradigm., Nakata H, Sakamoto K, Kakigi R, We investigated the effects of task repetition on the N140 and P300 components of event-related potentials (ERPs) in somatosensory Go/No-go paradigms. A Go or No-go stimulus was presented to the second or fifth digit of the left hand, respectively, at the same probability, and subjects had to respond by pushing a button with their right thumb as quickly as possible only after the presentation of a Go stimulus. The condition comprised seven sessions of recordings, and subjects were allowed to relax for five minutes after one session. The behavioral data for the reaction time (RT), standard deviation of RT, and error rates showed the absence of an effect by task repetition. In ERP waveforms, the amplitudes of N140 and P300 decreased with task repetition, and the latency of P300 was delayed by task repetition. There was no significant effect of task repetition on the peak latency of N140. Changes in amplitude and latency values in N140 and P300 during Go/No-go paradigms reflected changes in the neural activation of response execution and inhibition processing with task repetition. (C) 2015 Elsevier Ireland Ltd. All rights reserved., 2015, 594, 82, 86, Scientific journal, 10.1016/j.neulet.2015.03.055

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• Refereed, Eur J Neurosci, WILEY-BLACKWELL, Temporal dynamics of neural activity in motor execution and inhibition processing., Nakata H, Sakamoto K, Honda Y, Kakigi R, Although many neuroimaging studies using functional magnetic resonance imaging have shown the neuronal networks for motor execution and inhibition processing, the precise activation timing of each brain region is not yet well understood. In the present study, we investigated the temporal dynamics of neural activities in multiple brain regions using magnetoencephalography (MEG) and electroencephalography (EEG) simultaneously during somatosensory Go/No-go paradigms. The results of MEG showed that neural activities in the bilateral premotor area at approximately 150ms and in the primary motor cortex at approximately 250ms were only detected in Go trials, while brain responses in the bilateral prefrontal cortex at approximately 170ms were only observed in No-go trials. In addition, the amplitudes of the N140 and P300 components in EEG was significantly larger in No-go trials than in Go trials, and the latencies of N140 and P300 were significantly later in No-go trials than in Go trials. Our results indicated the time courses of neural processing in response execution and inhibition processing, and revealed differences in their underlying neural mechanisms., 2015, 41, 1448, 1458, Scientific journal, 10.1111/ejn.12889

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• Refereed, Am J Physiol Regul Integr Comp Physiol, Effects of passive heat stress on human somatosensory processing., Nakata H, Oshiro M, Namba M, Shibasaki M, 2015, 309, R1387, R1396
• Refereed, Front Hum Neurosci, FRONTIERS RESEARCH FOUNDATION, Activity of right premotor-parietal regions dependent upon imagined force level: an fMRI study, Mizuguchi N, Nakata H, Kanosue K, In this study, we utilized functional magnetic resonance imaging (fMRI) to measure blood oxygenation level-dependent (BOLD) signals. This allowed us to evaluate the relationship between brain activity and imagined force level. Subjects performed motor imagery of repetitive right hand grasping with three different levels of contractile force; 10%, 30%, and 60% of their maximum voluntary contraction (MVC). We observed a common activation among each condition in the following brain regions; the dorsolateral prefrontal cortex (DLPFC), ventrolateral prefrontal cortex (VLPFC), supplementary motor area (SMA), premotor area (PM), insula, and inferior parietal lobule (IPL). In addition, the BOLD signal changes were significantly larger at 60% MVC than at 10% MVC in the right PM, the right IPL, and the primary somatosensory cortex (SI). These findings indicate that during motor imagery right fronto-parietal activity increases as the imagined contractile force level is intensified. The present finding that the right brain activity during motor imagery is clearly altered depending on the imagined force level suggests that it may be possible to decode intended force level during the motor imagery of patients or healthy subjects., 2014, 8, 810, Scientific journal, 10.3389/fnhum.2014.00810

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• Refereed, Neurosci Lett, ELSEVIER IRELAND LTD, Effector-independent brain activity during motor imagery of the upper and lower limbs: An fMRI study, Mizuguchi N, Nakata H, Kanosue K, We utilized functional magnetic resonance imaging (fMRI) to evaluate the common brain region of motor imagery for the right and left upper and lower limbs. The subjects were instructed to repeatedly imagined extension and flexion of the right or left hands/ankles. Brain regions, which included the supplemental motor area (SMA), premotor cortex and parietal cortex, were activated during motor imagery. Conjunction analysis revealed that the left SMA and inferior frontal gyrus (IFG)/ventral premotor cortex (vPM) were commonly activated with motor imagery of the right hand, left hand, right foot, and left foot. This result suggests that these brain regions are activated during motor imagery in an effector independent manner. (C) 2014 Elsevier Ireland Ltd. All rights reserved., 2014, 581, 69, 74, Scientific journal, 10.1016/j.neulet.2014.08.025

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• Refereed, J Physiol Sci, SPRINGER JAPAN KK, Somato-motor inhibitory processing in humans: evidence from neurophysiology and neuroimaging, Nakata H, Sakamoto K, Honda Y, Kakigi R, Motor execution processing has been examined using an index of behavioral performance such as reaction times, kinetics, and kinematics. However, difficulties have been associated with the study of motor inhibitory processing because of the absence of actual behavioral performance. Therefore, non-invasive neurophysiological and neuroimaging methods including electroencephalography, magnetoencephalography, transcranial magnetic stimulation, and functional magnetic resonance imaging have been used to investigate neural processes in the central nervous system. We mainly reviewed research on somato-motor inhibitory processing based on data obtained by using these techniques, which can examine 'when', 'where, and 'how' motor inhibition occurs in the brain. Although to date a number of studies have used these techniques separately, few studies have utilized them in a comprehensive manner. In this review, we provide evidence that combining neurophysiological and neuroimaging methods should contribute to our understanding of how executive and inhibitory functions are implemented., 2014, 64, 233, 252, 10.1007/s12576-014-0320-0

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• Refereed, J Phys Fitness Sports Med, The Japanese Society of Physical Fitness and Sports Medicine, Differences in trunk rotation during baseball batting between skilled players and unskilled novices., Nakata H, Miura A, Yoshie M, Higuchi T, Kudo K, 2014, 3, 457, 466, Scientific journal, 10.7600/jpfsm.3.457

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• Refereed, Front Psychol, FRONTIERS RESEARCH FOUNDATION, Meditation reduces pain-related neural activity in the anterior cingulate cortex, insula, secondary somatosensory cortex, and thalamus, Nakata H, Sakamoto K, Kakigi R, Recent studies have shown that meditation inhibits or relieves pain perception.To clarify the underlying mechanisms for this phenomenon, neuroimaging methods, such as functional magnetic resonance imaging, and neurophysiological methods, such as magnetoencephalography and electroencephalography, have been used. However, it has been difficult to interpret the results, because there is some paradoxical evidence. For example, some studies reported increased neural responses to pain stimulation during meditation in the anterior cingulate cortex (ACC) and insula, whereas others showed a decrease in these regions. There have been inconsistent findings to date. Moreover, in general, since the activities of the ACC and insula are correlated with pain perception, the increase in neural activities during meditation would be related to the enhancement of pain perception rather than its reduction. These contradictions might directly contribute to the 'mystery of meditation.' In this review, we presented previous findings for brain regions during meditation and the anatomical changes that occurred in the brain with long-term meditation training. We then discussed the findings of previous studies that examined pain-related neural activity during meditation. We also described the brain mechanisms responsible for pain relief during meditation, and possible reasons for paradoxical evidence among previous studies. By thoroughly overviewing previous findings, we hypothesized that meditation reduces pain-related neural activity in the ACC, insula, secondary somatosensory cortex, and thalamus. We suggest that the characteristics of the modulation of this activity may depend on the kind of meditation and/or number of years of experience of meditation, which were associated with paradoxical findings among previous studies that investigated pain-related neural activities during meditation., 2014, 5, 1489, 10.3389/fpsyg.2014.01489

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• Refereed, Research journal of sport science in Nara Women's University, Nara Women's University, Differences in body size between left-handed and right-handed Japanese professional baseball players., Nakata H, The present study investigated differences in height, weight, and body mass index (BMI)between left-handed and right-handed Japanese professional baseball pitchers and batters.Some 345 pitchers and 356 batters who played in 2001, and 352 pitchers and 269 batters whoplayed in 2011 were evaluated. Analyses of variances (ANOVAs) revealed significantdifferences in height and weight, but not BMI, between left-handed and right-handed pitchersand batters. ANOVAs also showed a significant difference in body size between the players in2001 and 2011. The findings suggest that left-handed baseball pitchers and batters are smallerthan right-handed pitchers and batters in Japan as well as major league baseball., 2014, 16, 41, 45

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• Not Refereed, J Phys Fitness Sports Med, Relative age effects in Japanese athletes., Nakata H, Sakamoto K, 2014, 3, 467, 476
• Refereed, 東京体育学研究, 足関節筋の弛緩は手関節筋の皮質脊髄路興奮性を低下させる, Nakata Hiroki, 2013, 4, 5-9
• Refereed, J Appl Biomech, HUMAN KINETICS PUBL INC, The effect of fastball backspin rate on baseball hitting accuracy., Higuchi T, Morohoshi J, Nagami T, Nakata H, Kanosue K, The effectiveness of fastballs of equivalent speed can differ; for example, one element of this difference could be due to the effect of rate and orientation of ball spin on launched ball trajectory. In the present experiment, baseball batters' accuracy in hitting fastballs with different backspin rates at a constant ball velocity of 36 m/s was examined. Thirteen skilled baseball players (professionals, semiprofessionals, and college varsity players) participated in the study. The movements of bat and ball were recorded using two synchronized high-speed video cameras. The Pearson product-moment correlation coefficient (r) was calculated and used to analyze the relationship between ball backspin rate and the vertical distance between ball center and sweet spot at the moment of ball-bat impact. Ball backspin rate was positively correlated with increases in the distance from the optimal contact point of the swung bat (sweet spot) to the actual point of contact (r = .38, P < .001). Batters were most effective at the usual backspin rate for the ball velocity used. The decrease in accuracy of the batter's swing that was observed when the fastball's backspin deviated from the usual rate likely occurred because experienced batters predict ball trajectory from perceived ball speed., 2013, 29, 279, 284, Scientific journal
• Refereed, Percept Mot Skills, AMMONS SCIENTIFIC, LTD, Disturbance in hitting accuracy by professional and collegiate baseball players due to intentional change of target position., Higuchi T, Nagami T, Morohoshi J, Nakata H, Kanosue K, The present study investigated bat control of skilled baseball batters during tee batting, faced with an intentional change in target position. Twelve, skilled, male baseball players (M age = 24 yr., SD = 4) participated in the study. Participants were instructed to hit a baseball off a tee 0.8 m from the ground (Hitting condition), and also to deliberately swing just above the ball (Air Swing condition). The task for the participants was to perform, in alternate order, 15 swings at a real baseball on a stationary tee and 15 swings at an imaginary ball that was said to be on top of the real baseball. The participants were instructed to hit the ball toward center field just as they would hit in a game. While most participants could hit the real ball in the sweet area of the bat, only one participant did so in the Air Swing condition. Average distances from the center of the sweet area to ball center at the moment of ball-bat contact in the Air Swing condition (85 mm) were significantly greater than the distance in the Hitting condition (38 mm). The larger error in hitting an imaginary ball in the sweet area could be due to perceptual changes following the batter's altered focus, expectation of a lack of contact, and/or lack of feedback from the swing. It was suggested that baseball batters should be aware of the possible error in hitting accurately when they intentionally shifted the target., 2013, 116, 627, 639, Scientific journal, 10.2466/30.23.25.PMS.116.2.627-639

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• Refereed, Exp Brain Res, SPRINGER, Modulation of corticospinal excitability dependent upon imagined force level., Mizuguchi N, Umehara I, Nakata H, Kanosue K, Motor imagery is defined as the mental execution of a movement without any muscle activity. In the present study, corticospinal excitability was assessed by motor evoked potentials (MEPs) when the subjects imagined isometric elbow flexion at various force levels. Electromyography was recorded from the right brachioradialis, the biceps brachii and the triceps brachii muscles. First, the maximum voluntary contraction (MVC) of elbow flexion was recorded in each subject. Subjects practiced performing 10, 30 and 60 % MVC using visual feedback. After the practice, MEPs were recorded during the imagery of elbow flexion with the forces of 10, 30 and 60 % MVC without any feedback. After the MEPs recording, we assigned subjects to reproduce the actual elbow flexion force at 10, 30 and 60 % MVC. The MEPs amplitudes in the brachioradialis and biceps brachii in the 60 % MVC condition were significantly greater than those in the 10 % MVC condition (p < 0.05). These findings suggest that the enhancement of corticospinal excitability during motor imagery is associated with an increase in imagined force level., 2013, 230, 243, 249, Scientific journal, 10.1007/s00221-013-3649-3

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• Refereed, Neurosci Res, ELSEVIER IRELAND LTD, Brain activity during motor imagery of an action with an object: a functional magnetic resonance imaging study., Mizuguchi N, Nakata H, Hayashi T, Sakamoto M, Muraoka T, Uchida Y, Kanosue K, We utilized functional magnetic resonance imaging to investigate the brain regions activated during motor imagery of an action with an object both with and without passively holding the object. Participants performed the following tasks: (1) 'Imagery with Ball' condition: subjects imagined squeezing a foam ball (7 cm diameter) while holding the ball, (2) 'Imagery' condition: subjects imagined squeezing a ball without holding the ball, and (3) 'Ball' condition: subjects held the ball without motor imagery. Regions activated by the 'Imagery with Ball' condition were located in the left dorsolateral prefrontal cortex (DLPFC), supplemental motor areas (SMA), inferior parietal lobule (IPL), superior parietal lobule (SPL), insula, cerebellum and basal ganglia. A direct comparison revealed that the right DLPFC and the right IPL showed a higher level of activation during the 'Imagery with Ball' than during the 'Imagery' + 'Ball' conditions. Our studies suggested that the right front-parietal networks were involved in the motor imagery of an action with an object. (c) 2013 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved., 2013, 76, 150, 155, Scientific journal, 10.1016/j.neures.2013.03.012

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• Refereed, Percept Mot Skills, AMMONS SCIENTIFIC, LTD, Relative age effects in Japanese baseball: A historical analysis., Nakata H, Sakamoto K, The present study investigated the existence of the relative age effect, a biased distribution of birth dates, in Japanese professional baseball players born from 1911 to 1980. Japan applies a unique annual-age grouping for sport and education, which is from April 1 to March 31 of the following year. Thus, athletes were divided into four groups based on their month of birth; quarters Q1 (April-June), Q2 (July-September), Q3 (October-December), and Q4 (January-March of the following year). There were statistically biased distributions of birth dates among players born in the 1940s and subsequent decades (medium effects), and similar (but small) relative age effects were observed among players born in the 1910s, 1920s, and 1930s. The magnitude of the relative age effect changed with time, and socio-cultural factors such as international competition and media coverage may have contributed greatly to this effect., 2013, 117, 276, 289, Scientific journal, 10.2466/10.25.PMS.117x13z1

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• Refereed, J Strength Cond Res, LIPPINCOTT WILLIAMS & WILKINS, Relationship between performance variables and baseball ability in youth baseball players., Nakata H, Nagami T, Higuchi T, Sakamoto K, Kanosue K, Nakata, H, Nagami, T, Higuchi, T, Sakamoto, K, and Kanosue, K. Relationship between performance variables and baseball ability in youth baseball players. J Strength Cond Res 27(10): 2887-2897, 2013The present study investigated the relationship of performance variables and anthropometric measurements on baseball ability in 164 youth baseball players (age: 6.4-15.7 years). To evaluate their baseball performance, ball speeds in pitching and batting were recorded and kinetic energies of the pitched and hit balls were calculated. To record anthropometric and physical fitness characteristics, height and weight were measured and a battery of physical fitness tests covering standing long jump, side steps, sit-ups, 10-m sprint, trunk flexion, back strength, and grip strengths of both hands were conducted. The results of a multiple regression analysis revealed several significant predictors: age, body mass index (BMI), standing long jump, 10-m sprint, and grip strength for pitched ball kinetic energy and age, BMI, standing long jump, and back strength for hit ball kinetic energy. This study provides scientific evidence that relates certain specific physical performance tests and body characteristics with high achievement in the actual performance of pitching and batting. Youth players, their parents, coaches, and trainers would benefit by addressing these characteristics when planning training programs to improve the baseball performance of youth players., 2013, 27, 2887, 2897, Scientific journal, 10.1519/JSC.0b013e3182a1f58a

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• Refereed, J Strength Cond Res, LIPPINCOTT WILLIAMS & WILKINS, Electromyographic analysis of lower limbs during baseball batting., Nakata H, Miura A, Yoshie M, Kanosue K, Kudo K, We investigated the muscle activation pattern of lower limbs in baseball batting by recording surface electromyography (sEMG) from 8 muscles, the left and right rectus femoris (RF), biceps femoris (BF), tibialis anterior (TA), and medial gastrocnemius (MG) muscles. The muscle activities were compared between 10 skilled baseball players and 10 unskilled novices. The batting motion was divided into 7 phases: waiting, shifting body weight, stepping, landing, swing, impact, and follow through. The timing for these phases was analyzed by using a high-speed video camera. The onset latencies of sEMG were significantly earlier in baseball players at the left-RF (p < 0.01), right-BF (p < 0.05), and left-BF (p < 0.01). The peak amplitudes of sEMG activity were greater in skilled players at the right-RF (p < 0.01), right-BF (p < 0.01), left-BF (p < 0.01), left-TA (p < 0.01), right-MG (p < 0.01), and left-MG (p < 0.05). The timing for shifting, stepping, and landing was also significantly earlier in skilled players (p < 0.05, p < 0.01, and p < 0.05, respectively). Our findings suggest that preparations for the swing are made earlier in skilled baseball players who recruit their lower muscles for the swing more effectively than novices., 2013, 27, 5, 1179, 1187, Scientific journal, 10.1519/JSC.0b013e3182653ca9

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• Refereed, Clin Neurophysiol, Cortical rhythm of No-go processing in humans: An MEG study., Nakata H, Sakamoto K, Otsuka A, Yumoto M, Kakigi R, Objective: We investigated the characteristics of cortical rhythmic activity in No-go processing during somatosensory Go/No-go paradigms, by using magnetoencephalography (MEG). Methods: Twelve normal subjects performed a warning stimulus (S1) - imperative stimulus (S2) task with Go/No-go paradigms. The recordings were conducted in three conditions. In Condition 1, the Go stimulus was delivered to the second digit, and the No-go stimulus to the fifth digit. The participants responded by pushing a button with their right thumb for the Go stimulus. In Condition 2, the Go and No-go stimuli were reversed. Condition 3 was the resting control. Results: A rebound in amplitude was recorded in the No-go trials for theta, alpha, and beta activity, peaking at 600-900. ms. A suppression of amplitude was recorded in Go and No-go trials for alpha activity, peaking at 300-600. ms, and in Go and No-go trials for beta activity, peaking at 200-300. ms. Conclusion: The cortical rhythmic activity clearly has several dissociated components relating to different motor functions, including response inhibition, execution, and decision-making. Significance: The present study revealed the characteristics of cortical rhythmic activity in No-go processing. © 2012 International Federation of Clinical Neurophysiology., 2013, 124, 273, 282, Scientific journal, 10.1016/j.clinph.2012.06.019

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• Not Refereed, 体育の科学, 運動イメージとスキル, Nakata Hiroki, 2013, 63, 93-98
• Not Refereed, バイオメカニクス研究, 運動抑制に関わる脳内メカニズム, Nakata Hiroki, 2013, 17, 128-136
• Not Refereed, J Phys Fitness Sports Med, Motor imagery and sport performance., Mizuguchi N, Nakata H, Uchida Y, Kanosue K, 2012, 1, 103, 111
• Refereed, Neurosci Lett, ELSEVIER IRELAND LTD, Influence of somatosensory input on corticospinal excitability during motor imagery., Mizuguchi N, Sakamoto M, Muraoka T, Moriyama N, Nakagawa K, Nakata H, Kanosue K., Our previous studies showed that corticospinal excitability during imagery of squeezing a foam ball was enhanced by somatosensory input generated by passively holding the ball. In the present study, using the same experimental model, we investigated whether corticospinal excitability was influenced by holding the object with the hand opposite to the imagined hand. Corticospinal excitability was assessed by monitoring motor evoked potentials (MEPs) in the first dorsal interosseous muscle following transcranial magnetic stimulation over the motor cortex during motor imagery. Subjects were asked to imagine squeezing a foam ball with the right hand (experiment 1) or the left hand (experiment 2), while either holding nothing (Null condition), a ball in the right hand (Right condition) or a ball in the left hand (Left condition). The MEPs amplitude during motor imagery was increased, only when the holding hand and the imagined hand were on the same side. These results suggest that performance improvement and rehabilitation exercises will be more effective when somatosensory stimulation and motor imagery are done on the same side. (C) 2012 Elsevier Ireland Ltd. All rights reserved., 2012, 514, 127, 130, Scientific journal, 10.1016/j.neulet.2012.02.073

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• Refereed, J Strength Cond Res, LIPPINCOTT WILLIAMS & WILKINS, Electromyographic activity of lower limbs to stop baseball batting., Nakata H, Miura A, Yoshie M, Kudo K, Nakata, H, Miura, A, Yoshie, M, and Kudo, K. Electromyographic activity of lower limbs to stop baseball batting. J Strength Cond Res 26(6): 1461-1468, 2012-We investigated the muscle activation pattern of the lower limbs for the stopping motion of baseball batting by recording surface electromyography (EMG) from 8 muscles, the left and right rectus femoris (RF), biceps femoris (BF), tibialis anterior (TA), and medial gastrocnemius (MG) muscles. First, muscle activities for 'Swing' and 'Stopping' trials were examined in 10 skilled baseball players and 10 unskilled novices. Second, the characteristics of EMG activities for 'Stopping' were compared between the 2 groups. The peak latencies of EMG were significantly shorter in 'Stopping' than in 'Swing' at the right-TA, left-BF, and left-MG between both groups. The peak amplitudes of EMG activity were significantly larger in 'Swing' than in 'Stopping' at the right-TA, left-BF, and left-MGin both groups. In addition, the peak amplitudes of EMGactivity for 'Stopping' were significantly larger in the players than in novices at the right-RF and right-TA. The characteristics of EMG activity clearly differed between 'Swing' and 'Stopping', and between baseball players and nonplayers, indicating that evaluating the EMG activity in batting enables the understanding of proficiency. Our findings should help players, novices, and coaches to optimize batting performance., 2012, 26, 6, 1461, 1468, Scientific journal, 10.1519/JSC.0b013e318231ab12

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• Refereed, Eur J Appl Physiol, SPRINGER, The relationship between reaction time and response variability and somatosensory No-go potentials., Nakata H, Sakamoto K, Kakigi R, We investigated the relationship between reaction time (RT) and response variability and somatosensory Go/No-go potentials. Event-related potentials following electrical stimulation of the second (Go stimulus) or fifth (No-go stimulus) digit of the left hand were recorded from 16 subjects, and Go and No-go stimuli were presented at an even probability. The subjects were instructed to respond to the Go stimuli by pushing a button with their right thumb. We analyzed the correlation between RT and the N140 and P300 components, and between the standard deviation (SD) of RT and the N140 and P300. Neither the amplitude nor latency of the No-go-N140 (N140 evoked by No-go stimuli) or the Go-N140 (N140 evoked by Go stimuli) related significantly with RT and the SD of RT. There was a significant negative correlation between RT and the amplitude of the No-go-P300 (P300 evoked by No-go stimuli) at Fz and C3, indicating that subjects with a shorter RT had a No-go-P300 of larger amplitude. The latency of the Go-P300 (P300 evoked by Go stimuli) at Pz and C3 showed a significant correlation with RT. The SD of RT was significantly correlated with the amplitudes of the No-go-P300 at C3 and Go-P300 at Pz and C4, and the latency of the No-go-P300 at Cz and Go-P300 at Fz, Cz, Pz, C3, and C4. Our results suggest that response speed and variability for the Go stimulus in Go/No-go paradigms affect No-go-related neural activity for the No-go stimulus., 2012, 112, 207, 214, Scientific journal, 10.1007/s00421-011-1973-5

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• Refereed, Percept Mot Skills, AMMONS SCIENTIFIC, LTD, Association of relative age effects in sports with number of years in school., Nakata H, Sakamoto K, The present study investigated the association of the relative age effect, a biased distribution of birth dates, with a high school versus university background in Japanese professional soccer and baseball players. The number of athletes born in the first quarter (April June) was larger than the number born in the fourth quarter (January March) for both soccer and baseball; however, the magnitude of the relative age effect differed with years in school. The skew of birth dates was stronger among players who only graduated high school than those who graduated university or college. This phenomenon was confirmed in both baseball and soccer players. The findings suggest relative age effects in professional sports to be related to years of age and years in school., 2012, 115, 166, 170, Scientific journal, 10.2466/10.05.11.PMS.115.4.166-170

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• Refereed, J Strength Cond Res, Differences in the head movement during baseball batting between skilled players and novices., Nakata H, Miura A, Yoshie M, Kudo K, 2012, 26, 2632, 2640
• Refereed, Percept Mot Skills, AMMONS SCIENTIFIC, LTD, Sex differences in relative age effects among Japanese athletes., Nakata H, Sakamoto K., The present study investigated the relative age effect (RAE), a biased distribution of elite athletes' birthdates, in Japanese female athletes. Japan applies a unique annual-age grouping for sport and education, which is from April 1 to March 31 of the following year. A total of 1,335 female athletes were evaluated from six sports: softball, soccer, volleyball, basketball, badminton, and track and field (long distance), and compared with male athletes. All athletes played in the top level of Japanese leagues for each sport in 2010. Distribution of the birth dates in each female sport showed a significant RAE only in volleyball. For males, significant RAEs were observed in baseball, soccer, and track and field. Findings suggest that the determinants of RAEs in sports may differ between males and females., 2012, 115, 179, 186, Scientific journal, 10.2466/10.05.17.PMS.115.4.179-186

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• Refereed, J Adv Com Intell Intell Inform, Neurophysiological and dynamical control principles underlying variable and stereotyped movement patterns in the process of motor skill acquisition., Kudo K, Miyazaki M, Sekiguchi H, Kadota H, Fujii S, Miura A, Yoshie M, Nakata H., 2011, 15, 942, 953
• Refereed, PLoS One, PUBLIC LIBRARY SCIENCE, The modulation of corticospinal excitability during motor imagery of actions with objects., Mizuguchi N, Sakamoto M, Muraoka T, Nakagawa K, Kanazawa S, Nakata H, Moriyama N, Kanosue K, We investigated whether corticospinal excitability during motor imagery of actions (the power or the pincer grip) with objects was influenced by actually touching objects (tactile input) and by the congruency of posture with the imagined action (proprioceptive input). Corticospinal excitability was assessed by monitoring motor evoked potentials (MEPs) in the first dorsal interosseous following transcranial magnetic stimulation over the motor cortex. MEPs were recorded during imagery of the power grip of a larger-sized ball (7 cm) or the pincer grip of a smaller-sized ball (3 cm) with or without passively holding the larger-sized ball with the holding posture or the smaller-sized ball with the pinching posture. During imagery of the power grip, MEPs amplitude was increased only while the actual posture was the same as the imagined action (the holding posture). On the other hand, during imagery of the pincer grip while touching the ball, MEPs amplitude was enhanced in both postures. To examine the pure effect of touching (tactile input), we recorded MEPs during imagery of the power and pincer grip while touching various areas of an open palm with a flat foam pad. The MEPs amplitude was not affected by the palmer touching. These findings suggest that corticospinal excitability during imagery with an object is modulated by actually touching an object through the combination of tactile and proprioceptive inputs., 2011, 6, e26006, Scientific journal, 10.1371/journal.pone.0026006

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• Refereed, Med Sci Sports Exerc, LIPPINCOTT WILLIAMS & WILKINS, Spin on fastball thrown by elite baseball pitchers., Nagami T, Morohoshi J, Higuchi T, Nakata H, Naito S, Kanosue K, NAGAMI, T., J. MOROHOSHI, T. HIGUCHI, H. NAKATA, S. NAITO, and K. KANOSUE. Spin on Fastballs Thrown by Elite Baseball Pitchers. Med. Sci. Sports Exerc., Vol. 43, No. 12, pp. 2321-2327, 2011. Purpose: In this study, we analyzed the direction of the spin axis angles and the spin rate of baseballs pitched by elite collegiate and professional pitchers. Method: The video image of a ball being pitched was taken from the period just before release until 200 ms after release with a high-speed video camera at a rate of 1000 frames per second. A custom-made device was used to analyze the spin axis angle and the spin rate. Results and Conclusion: There were no significant differences in the direction of the spin axis angles or the spin rate between collegiate and professional pitchers. A significant correlation was obtained between spin rate and ball speed; that is, the higher the ball speed, the greater the spin rate. In addition, the spin rate deviated more across subjects than did ball speed. For all subjects, the azimuth and elevation of spin axis were 19 degrees +/- 14 degrees and -32 degrees +/- 9 degrees, respectively. Some of the pitchers were able to put a characteristic spin on their fastball; the nature of this spin could be related to their pitching success., 2011, 43, 2321, 2327, Scientific journal, 10.1249/MSS.0b013e318220e728

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• Refereed, Percept Mot Skills, AMMONS SCIENTIFIC, LTD, Relative age effect in Japanese male athletes., Nakata H, Sakamoto K, The present study investigated the relative age effect, a biased distribution of elite athletes' birthdates, in Japanese male athletes. Japan applies a unique annual-age grouping for sport and education, which is from April 1 to March 31 of the following year. A total of 4,318 male athletes was evaluated from 12 sports: baseball, soccer, basketball, volleyball, handball, golf, horse racing, rugby, American football, sumo, Ekiden (track and field in long distance), and badminton. They played in the top level of Japanese leagues for each sport in 2010. The distribution of the birth dates was examined in each sport and showed significant relative age effect in baseball, soccer, volleyball, Ekiden, basketball, sumo, and horse racing, but not in all sports. The findings suggest that although the school year in Japan starts on April 1, significant relative age effects are observed in some sporting events., 2011, 113, 570, 574, Scientific journal, 10.2466/05.10.11.PMS.113.5.570-574

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• Refereed, NeuroReport, LIPPINCOTT WILLIAMS & WILKINS, The relationship in gating effects between short- and long-latency SEPs., Nakata H, Sakamoto K, Yumoto M, Kakigi R, We investigated the relationship between short-latency and long-latency somatosensory-evoked potentials (SEPs) relating to voluntary movement. In general, the amplitudes of short-latency components in SEPs are attenuated during movement, whereas those of long-latency are enhanced, and this phenomenon is termed 'gating effects'. This study aimed to examine the relationship of changes in amplitude between short-latency and long-latency SEPs. SEPs were recorded from 11 participants at Fz, Cz, Pz, and C4' by stimulating the left median nerve. Two tasks were conducted; Control and Movement. In Control, the participant was asked to relax with no specific task. In Movement, the participant was encouraged to continue a rapid drumming motion of all fingers of the left hand at a self-paced rate. The amplitudes of short-latency SEPs, the P25 at C4' and N30 at Fz, were significantly smaller in the Movement than Control condition. By contrast, the amplitudes of long-latency SEPs, the N140 at Fz, Cz, and Pz were significantly larger in Movement than Control condition. Moreover, a significant positive correlation was observed in the rate of amplitude change between the frontal N30 and vertex N140, indicating that for the participants with a frontal N30 of smaller amplitude during Movement, the amplitude of the vertex N140 was smaller. We inferred that the neural activities in movement-related cortices affected the sources for the frontal N30 and vertex N140 in the same neuronal network simultaneously. NeuroReport 22:1000-1004 (C) 2011 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins., 2011, 22, 1000, 1004, Scientific journal, 10.1097/WNR.0b013e32834dc296

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• Refereed, Neurosci Res, ELSEVIER IRELAND LTD, A difference exists in somatosensory processing between the anterior and posterior parts of the tongue., Sakamoto K, Nakata H, Inui K, Perrucci MG, Del Gratta C, Kakigi R, Romani GL, The somatic sensation of the tongue is necessary for daily life, but it is difficult to know the underlying neural mechanisms. In particular, because of the vomiting reflex and several morphological problems, no neuroimaging studies have examined somatosensory processing by stimulating the posterior part of the tongue, except for two magnetoencephalographic studies (Sakamoto et al., 2008a,b). This is the first study to clarify the human cortical processing for sensory perception by the posterior part of the tongue with a newly developed device and functional magnetic resonance imaging (fMRI). Stimulation of the left and right postero-lateral parts of the tongue induced significant activity in the primary somatosensory cortex (SI) and Brodmann area 40 in the right hemisphere and the anterior cingulate cortex (ACC). In contrast, antero-lateral stimulation produced activity only in the right SI. The activated region in SI was significantly larger following stimulation of the posterior than anterior part. These results indicate that a clear difference exists in somatosensory processing between stimulation of the antero-lateral and postero-lateral parts of the tongue, and a right hemisphere is dominant for the stimulation of both antero-lateral and postero-lateral areas. The activity in BA 40 and ACC may imply that the posterior of the tongue belongs to the visceral system. (C) 2009 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved., 2010, 66, 173, 179, Scientific journal, 10.1016/j.neures.2009.10.013

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• Refereed, Anti-Aging Medicine, Japanese Society of Anti-Aging Medicine, Effect of mastication on human brain activity., Sakamoto K, Nakata H, Yumoto M, Kakigi R, Mastication is a complicated movement generated from a neural population in the brainstem and a neural network involving several brain regions. Recently, attention has been focused on the relationship between mastication and age-related decline in human cognitive function, but the neural mechanisms underlying this association remain unknown. In this article, we review research on the effect of mastication based on data obtained using event-related potentials (ERPs), including the P300 component and contingent negative variation (CNV), motor-related cortical potentials (MRCPs), and reaction time (RT) as behavioral data. The peak latency of P300 and RT clearly shortened with the repetition of sessions in Mastication, but not in Control, Jaw Movement, or Finger Tapping. The mean amplitude of CNV differed between the Mastication and Control conditions with the repetition of sessions. By contrast, there was no significant difference in the amplitude of MRCP between Mastication and Control in any of the sessions. These results suggest that mastication is associated with cognitive processing rather than movement-related processing in the human brain. We believe that non-invasive recording methods, such as electroencephalography (EEG), magnetoencephalography (MEG), transcranial magnetic stimulation (TMS), functional magnetic resonance imaging (fMRI), and near-infrared spectroscopy (NIRS), will supply valuable evidence in support of a positive relationship between mastication and cognition., 2010, 7, 13, 153, 160, 10.3793/jaam.7.153

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• Refereed, Front Physiol, FRONTIERS RESEARCH FOUNDATION, Somatosensory processing of the tongue in humans., Sakamoto K, Nakata H, Yumoto M, Kakigi R, We review research on somatosensory (tactile) processing of the tongue based on data obtained using non-invasive neurophysiological and neuroimaging methods. Technical difficulties in stimulating the tongue, due to the noise elicited by the stimulator, the fixation of the stimulator, and the vomiting reflex, have necessitated the development of specialized devices. In this article, we show the brain activity relating to somatosensory processing of the tongue evoked by such devices. More recently, the postero-lateral part of the tongue has been stimulated, and the brain response compared with that on stimulation of the antero-lateral part of the tongue. It is likely that a difference existed in somatosensory processing of the tongue, particularly around primary somatosensory cortex, Brodmann area 40, and the anterior cingulate cortex., 2010, 1, 136, 145, 10.3389/fphys.2010.00136

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• Refereed, Brain Res Review, ELSEVIER SCIENCE BV, Characteristics of the athletes' brain: Evidence from neurophysiology and neuroimaging., Nakata H, Yoshie M, Miura A, Kudo K, We review research on athletes' brains based on data obtained using non-invasive neurophysiological and neuroimaging methods; these data pertain to cognitive processing of visual, auditory, and somatosensory (tactile) stimulation as well as to motor processing, including preparation, execution, and imagery. It has been generally accepted that athletes are faster, stronger, able to jump higher, more accurate, more efficient, more consistent, and more automatic in their sports performances than non-athletes. These claims have been substantiated by neuroscientific evidence of the mechanisms underlying the plastic adaptive changes in the neuronal circuits of the brains of athletes. Reinforced neural networks and plastic changes are induced by the acquisition and execution of compound motor skills during extensive daily physical training that requires quick stimulus discrimination, decision making, and specific attention. In addition, it is likely that the manner of neuronal modulation differs among sports. We also discuss several problems that should be addressed in future studies. (C) 2009 Elsevier B.V. All rights reserved, 2010, 62, 2, 197, 211, 10.1016/j.brainresrev.2009.11.006

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• Refereed, Neurosci Lett, ELSEVIER IRELAND LTD, Characteristics of No-go P300 component during somatosensory Go/No-go paradigms., Nakata H, Sakamoto K, Kakigi R, The present study investigated one of the characteristics of No-go-related brain activity during somatosensory Go/No-go paradigms, by manipulating the stimulus site and response hand. Somatosensory event-related potentials (ERPs) were recorded in ten right-handed subjects. Electrical stimulation was delivered to the second and fifth digit of one hand, and the subjects had to respond to a Go stimulus by pushing a button with the thumb contralateral to the stimulated side as quickly as possible. We focused on the peak amplitude and latency of Som-Go-P300 (P300 evoked by somatosensory Go stimuli) and Som-No-go-P300 (P300 evoked by somatosensory No-go stimuli) components. The amplitude of Som-No-go-P300, which is very similar to No-go-P300 components following visual and auditory stimulation, was significantly larger than that of Som-Go-P300 at fronto-central electrodes, indicating 'anteriorization' of the No-go-P300. The amplitude of Som-No-go-P300 was significantly larger in right than left hemispheres during right hand response conditions, but this difference was not found under left hand conditions. In addition, the difference in amplitude between Som-Go- and Som-No-go-P300, which is frequently described as 'the Go/No-go effect' on P300, was significant in the left hemisphere under right hand response conditions, whereas a significant effect was found in both the left and the right hemispheres under left hand response conditions. Our findings suggested that the anteriorization of No-go-P300 was independent of stimulus modalities such as visual, auditory, and somatosensory, and the amplitude of No-go-P300 and Go/No-go effects on P300 was affected by the response hand. (c) 2010 Elsevier Ireland Ltd. All rights reserved., 2010, 478, 124, 127, Scientific journal, 10.1016/j.neulet.2010.05.002

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• Refereed, NeuroReport, LIPPINCOTT WILLIAMS & WILKINS, Effects of the interstimulus interval on somatosensory go/no-go event-related potentials., Nakata H, Sakamoto K, Kakigi R, This study investigated the characteristics of event-related potentials using somatosensory go/no-go paradigms. We manipulated the interstimulus interval and analyzed its effect on the peak amplitude and latency of the N140 and P300 components. The amplitude of N140 increased as the interstimulus interval increased, and was significantly larger in no-go than in go trials at the 1-s and 2-s interstimulus intervals, but not the 4-s and 6-s interstimulus intervals. The amplitude of P300 also increased with the interstimulus interval, and was significantly larger in no-go than in go trials at all interstimulus intervals. The reaction time in go trials was longer with increasing interstimulus interval. This study suggests that brain activities associated with go/no-go decisional processes are influenced by the interstimulus interval. NeuroReport 21:1040-1044 (C) 2010 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins., 2010, 21, 1040, 1044, Scientific journal, 10.1097/WNR.0b013e32833f7bb5

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• Refereed, J Neurophysiol, AMER PHYSIOLOGICAL SOC, Time course of activity in itch-related brain regions: A combined MEG-fMRI study., Mochizuki H, Inui K, Tanabe C.H, Akiyama F.L, Otsuru N, Yamashiro K, Sasaki A, Nakata H, Sadato N, Kakigi R, Mochizuki H, Inui K, Tanabe HC, Akiyama LF, Otsuru N, Yamashiro K, Sasaki A, Nakata H, Sadato N, Kakigi R. Time course of activity in itch-related brain regions: a combined MEG-fMRI study. J Neurophysiol 102: 2657-2666, 2009. First published August 26, 2009; doi: 10.1152/jn.00460.2009. Functional neuroimaging studies have identified itch-related brain regions. However, no study has investigated the temporal aspect of itch-related brain processing. Here this issue was investigated using electrically evoked itch in ten healthy adults. Itch stimuli were applied to the left wrist and brain activity was measured using magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI). In the MEG experiment, the magnetic responses evoked by the itch stimuli were observed in the contralateral and ipsilateral frontotemporal regions. The dipoles associated with the magnetic responses were mainly located in the contralateral (nine subjects) and ipsilateral (eight subjects) secondary somatosensory cortex (SII)/insula, which were also activated by the itch stimuli in the fMRI experiment. We also observed an itch-related magnetic response in the posterior part of the centroparietal region in six subjects. MEG and fMRI data showed that the magnetic response in this region was mainly associated with itch-related activation of the precuneus. The latency was significantly longer in the ipsilateral than that in the contralateral SII/insula, suggesting the difference to be associated with transmission in the callosal fibers. The timing of activation of the precuneus was between those of the contralateral and ipsilateral SII/insula. Other sources were located in the premotor, primary motor, and anterior cingulate cortices (one subject each). This study is the first to demonstrate part of the time course of itch-related brain processing. Combining methods with high temporal and spatial resolution (e.g., MEG and fMRI) would be useful to investigate the temporal aspect of the brain mechanism of itch., 2009, 102, 2657, 2666, Scientific journal, 10.1152/jn.00460.2009

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• Refereed, Neurosci Lett, ELSEVIER IRELAND LTD, Negative BOLD during tongue movement: A functional magnetic resonance imaging study., Sakamoto K, Nakata H, Perrucci GM, Del Gratta C, Kakigi R, Romani GL, The aim of this functional magnetic resonance imaging (fMRI) study was to evaluate negative blood oxygen level-dependent (BOLD) signals during voluntary tongue movement. Deactivated (Negative BOLD) regions included the posterior parietal cortex (PPC), precuneus, and middle temporal gyrus. Activate (Positive BOLD) regions included the primary somatosensory-motor area (SMI), inferior parietal lobular medial frontal gyrus, superior temporal gyrus. insula, lentiform nucleus, and thalamus. The results were not consistent with previous studies involving unilateral hand and finger movements showing the dead activation of motor-related cortical areas including the ipsilateral MI. The areas of Negative BOLD in the PPC and precuneus might reflect specific neural networks relating to voluntary tongue movement. (C) 2009 Elsevier Ireland Ltd. All rights reserved., 2009, 466, 120, 123, Scientific journal, 10.1016/j.neulet.2009.09.038

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• Refereed, Neurosci Res, ELSEVIER IRELAND LTD, The effect of mastication on human motor preparation processing: A study with CNV and MRCP., Sakamoto K, Nakata H, Honda Y, Kakigi R, To clarify the effect of mastication on motor preparation processing using electroencephalography (EEG), we investigated the effect of mastication on contingent negative variation (CNV) and reaction time (RT) in Experiment 1, and movement-related cortical potentials (MRCPs) in Experiment 2. The twelve subjects performed four CNV or MRCP sessions, and in the Mastication condition chewed a gum base during the resting period between sessions, Pre (before chewing) and Post 1, 2, and 3 (after chewing). In the Control condition, the subjects performed the same sessions without chewing gum during the intervals between sessions on another day. In Experiment 1, the mean amplitudes of the early- and late-CNV were significantly larger in Mastication than Control at Post 2 and Post 3. RT also differed significantly between Mastication and Control at Post 3. By contrast, in Experiment 2, there were no significant differences between Mastication and Control for the mean amplitudes of MRCPs including Bereitschaftspotential (BP) and negative slope (NS') in any session. These results suggest that mastication influences cognitive processing reflected by CNV with stimulus-triggered movement, rather than motor-related processing reflected by MRCPs relating to self-initiated movement, and provide evidence concerning the mechanisms for the effect of mastication on the human brain. (c) 2009 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved., 2009, 64, 259, 266, Scientific journal, 10.1016/j.neures.2009.03.008

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• Refereed, Clin Neurophysiol, ELSEVIER IRELAND LTD, The effect of mastication on human cognitive processing: A study using event-related potentials., Sakamoto K, Nakata H, Kakigi R, Objective: The purpose of the present Study was to clarify the effect of mastication on cognitive processing using reaction time (RT) and event-related potentials (ERPs). Methods: The two experiments consisted of two conditions, Mastication (chewing gum) and Control (relaxing Without chewing gum) in Experiment 1, and law Movement (opening and closing the jaw) and Finger Tapping (tapping the right index finger) in Experiment 2. The subjects performed four sessions of an auditory oddball paradigm. RT and ERPs were recorded in these four sessions, Pre (before chewing), and Post 1, Post 2 and Post 3 (after chewing). Results: In Mastication for RT and the peak latencies of P300 and N100. the values were significantly longer in Pre than in Post 2 or Post 3. By contrast, in Control, jaw Movement, and Finger Tapping, they were almost identical among sessions or significantly shorter in Pre than in Post 2 or Post 3. Conclusions: Mastication influences cognitive processing time as reflected by RT and the latency of ERP waveforms. Significance: This is the first study investigating the effect of mastication on the central nervous system using event-related potentials. (C) 2008 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., 2009, 120, 41, 50, Scientific journal, 10.1016/j.clinph.2008.10.001

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• Refereed, NeuroReport, LIPPINCOTT WILLIAMS & WILKINS, The characteristics of no-go potentials with intraepidermal stimulation., Nakata H, Sakamoto K, Inui K, Hoshiyama M, Kakigi R, The objective of this study was to investigate whether no-go potentials during go/no-go tasks were observed after painful stimulation using intratepidermal electrical stimulation. Event-related potentials were recorded by stimulating the medial or lateral side of the left-hand dorsum. Peak amplitudes of N2 and P3 were significantly larger in no-go trials than in go trials at frontocentral electrodes during go/no-go task, but the differences were not found during rest control and choice reaction time tasks. These characteristics of no-go-related potentials were very similar to event-related potential waveforms during visual, auditory, and somatosensory go/no-go tasks. We suggest that cortical activities relating to response inhibitory processing are not dependent on the sensory modality used. NeuroReport 20:1149-1154 (C) 2009 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins., 2009, 20, 1149, 1154, Scientific journal, 10.1097/WNR.0b013e32832f81d6

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• Refereed, Neurosci Lett, ELSEVIER IRELAND LTD, Negative BOLD effect on somato-motor inhibitory processing: an fMRI study., Nakata H, Sakamoto K, Ferretti A, Perrucci GM, Del Gratta C, Kakigi R, Romani GL, Inhibiting inappropriate behavior and thoughts in the current context is an essential ability for humans, but the neural mechanisms for response inhibitory processing are a matter of continuous debate. The aim of this event-related functional magnetic resonance imaging (fMRI) study was to evaluate the negative blood oxygen level dependent (BOLD) effect on inhibitory processing during go/no-go paradigms. Fifteen subjects performed two different types of somatosensory go/no-go paradigm: (1) button press and (2) count. Go and no-go stimuli were presented with an even probability. We observed a common negative activation during Movement No-go and Count No-go trials in the right SFG, corresponding to BA 8. These findings suggest that the right SFG region was responsible for the negative BOLD effect on inhibitory processing, which was independent of the required response mode. We hypothesized several possible explanations for the deactivation of the SFG during no-go trials. (c) 2009 Elsevier Ireland Ltd. All rights reserved., 2009, 462, 101, 104, Scientific journal, 10.1016/j.neulet.2009.06.088

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• Refereed, NeuroImage, ACADEMIC PRESS INC ELSEVIER SCIENCE, Centrifugal modulation of human LEP components to a task-relevant noxious stimulation triggering voluntary movement., Nakata H, Sakamoto K, Honda Y, Mochizuki H, Hoshiyama M, Kakigi R, In the present study, we investigate the top-down centrifugal modulation of neural responses to a task-relevant noxious stimulation triggering voluntary movement by recording magnetoencephalography (MEG) and electroencephalography (EEG) simultaneously. An auditory warning signal was followed 2-3 s later by a noxious YAG laser stimulation as an imperative signal delivered to the left hand dorsum. Ten normal subjects performed three different conditions, Control, Movement, and Count. In Control, the subjects were asked to relax and rest quietly with no task. In Movement, the subjects extended the left index finger after imperative stimuli. In Count, the subjects counted the number of imperative stimuli silently. The amplitude of the N2 component recorded by EEG, which peaked about 220 ms after noxious stimulation, was significantly attenuated in Movement, but not in Count, compared to Control. The root-mean-square (RMS) from both hemispheres, and areal mean signal (AMS) amplitudes and the equivalent current dipole (ECD) strengths from SI/PPC and bilateral SII recorded at around 170 ms by MEG were not significantly different among the three conditions. In contrast, ECD strengths and AMS amplitudes from the anterior cingulate cortex (ACC), which showed a similar peak to the N2 component, were smaller in Movement than Control and Count. We therefore suspect that neural activities related to generator mechanisms of N2, especially including ACC, are inhibited by movement-related neural activities during the preparatory period. The present findings indicate a characteristic of pain-motor integration in a movement preparatory period. (C) 2008 Published by Elsevier Inc., 2009, 45, 129, 142, 10.1016/j.neuroimage.2008.11.026

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• Refereed, Clin Neurophysiol, Neural responses related to point-light walker perception: a magnetoencephalographic study., Hirai M, Kaneoke Y, Nakata H, Kakigi R, 2008, 119, 2775, 2784
• Refereed, Clin Neurophysiol, ELSEVIER IRELAND LTD, Somatotopic representation of the tongue in human secondary somatosensory cortex., Sakamoto K, Nakata H, Kakigi R, Objective: To clarify the somatotopic representation of the tongue secondary somatosensory cortex (SII) in humans. Methods: Somatosensory evoked magnetic fields (SEFs) were recorded from nine Subjects after stimulating four body sites, left,micro (LA) and postero (LP) lateral margins of the tongue, left median nerve at the wrist (Hand), and left tibial nerve at the ankle (Foot). Results: Clear neural activities were recorded from the bilateral SII in both hemispheres after the four sites were stimulated. The tongue SII for LA and LP was located close to the hand SII and significantly more anterior than the Foot SII There was no significant difference in the location of dipoles between the LA and LP areas of the tongue SII The mean peak latencies of the tongue SII for LA and LP were significantly shorter in the hemisphere contralateral to the stimulation than the ipsilateral hemisphere. Conclusions: The tongue areas are considered to occupy a small region in SII with insufficient spatial separation to differentiate anterior from posterior areas even using magnetoencephalography which has a higher spatial resolution than electroencephalography (EEG). Significance: This is the first systematical Study to clarify the activated regions in SII following stimulation of the tongue. (c) 2008 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., 2008, 119, 2125, 2134, Scientific journal, 10.1016/j.clinph.2008.05.003

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• Refereed, Clin Neurophysiol, ELSEVIER IRELAND LTD, Somatosensory-evoked magnetic fields following stimulation of the tongue in humans., Sakamoto K, Nakata H, Kakigi R, Objective: To clarify the characteristics relating to the temporal dynamics of the tongue primary somatosensory cortex (SI). Methods: We fabricated individual intraoral devices and recorded somatosensory-evoked magnetic fields (SEFs) from 10 normal subjects. The tongue was stimulated with a concentrated bipolar electrode in four areas: the right and left antero-lateral margins, and the right and left postero-lateral margins. Results: The primary component was recorded about 19 ms post-stimulation. Six components, termed 1M, 2M, 3M, 4M, 5M, and 6M, respectively, were found within 130 ms of the stimulation. These activities were detected in hemispheres both contralateral and ipsilateral to the stimulation, and were estimated to be located around the tongue SI. In addition, the latency of the contralateral hemisphere was significantly shorter than that of the ipsilateral hemisphere for all components, independent of the area stimulated. Conclusions: Tactile stimulation of the tongue-elicited activity in the tongue SI in both hemispheres. Significance: This is the first study to investigate the brain responses evoked by stimulating different areas of the tongue, using magnetoencephalography. (C) 2008 International Federation of Clinical Neuro physiology. Published by Elsevier Ireland Ltd. All rights reserved., 2008, 119, 1664, 1673, Scientific journal, 10.1016/j.clinph.2008.03.029

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• Refereed, Cereb Cortex, OXFORD UNIV PRESS INC, Temporal dynamics of adaptation to natural sounds in the human auditory cortex., Altmann CF, Nakata H, Noguchi Y, Inui K, Hoshiyama M, Kaneoke Y, Kakigi R, We aimed at testing the cortical representation of complex natural sounds within auditory cortex by conducting 2 human magnetoencephalography experiments. To this end, we employed an adaptation paradigm and presented subjects with pairs of complex stimuli, namely, animal vocalizations and spectrally matched noise. In Experiment 1, we presented stimulus pairs of same or different animal vocalizations and same or different noise. Our results suggest a 2-step process of adaptation effects: first, we observed a general item-unspecific reduction of the N1m peak amplitude at 100 ms, followed by an item-specific amplitude reduction of the P2m component at 200 ms after stimulus onset for both animal vocalizations and noise. Multiple dipole source modeling revealed the right lateral Heschl's gyrus and the bilateral superior temporal gyrus as sites of adaptation. In Experiment 2, we tested for cross-adaptation between animal vocalizations and spectrally matched noise sounds, by presenting pairs of an animal vocalization and its corresponding or a different noise sound. We observed cross-adaptation effects for the P2m component within bilateral superior temporal gyrus. Thus, our results suggest selectivity of the evoked magnetic field at 200 ms after stimulus onset in nonprimary auditory cortex for the spectral fine structure of complex sounds rather than their temporal dynamics., 2008, 18, 1350, 1360, Scientific journal, 10.1093/cercor/bhm166

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• Refereed, Brain Res Bull, PERGAMON-ELSEVIER SCIENCE LTD, Executive functions with different motor outputs in somatosensory Go/Nogo tasks: an event-related functional MRI study., Nakata H, Sakamoto K, Ferretti A, Perrucci GM, Del Gratta C, Kakigi R, Romani GL, The aim of this event-related functional magnetic resonance imaging (fMRI) study was to investigate and compare executive functions with different motor outputs in somatosensory Go/Nogo tasks: (1) Button press and (2) Count. Go and Nogo stimuli were presented with an even probability. We observed a common network for Movement and Count Go trials in several regions of the brain including the dorsolateral (DLPFC) and ventrolateral prefrontal cortices (VLPFC), supplementary motor area (SMA), posterior parietal cortex (PPC), inferior parietal lobule (IPL), Insula, and superior temporal gyrus (STG). Direct comparison revealed that primary sensorimotor area (SMI), premotor area (PM), and anterior cingulate cortex (ACC) were more activated during Movement than Count Go trials. In contrast, the VLPFC was more activated during Count than Movement Go trials. Our results suggest that there were two neural networks for the supramodal executive function, common and uncommon, depending on the required response mode. (c) 2008 Elsevier Inc. All rights reserved., 2008, 77, 197, 205, Scientific journal, 10.1016/j.brainresbull.2008.07.008

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• Refereed, NeuroImage, ACADEMIC PRESS INC ELSEVIER SCIENCE, Evoked magnetic fields following noxious laser stimulation of the thigh in humans., Nakata H, Tamura Y, Sakamoto K, Akatsuka K, Hirai M, Inui K, Hoshiyama M, Saitoh Y, Yamamoto T, Katayama Y, Kakigi R, Primary somatosensory cortex (SI) and posterior parietal cortex (PPC) are activated by noxious Stimulation. In neurophysiological studies using magnetoencephalography (MEG), however, it has been difficult to separate the activity in SI from that in PPC following stimulation of the upper limb, since the hand area of SI is very close to PPC. Therefore, we investigated human pain processing using MEG following the application of a thulium-YAG laser to the left thigh to separate the activation of SI and PPC, and to clarify the time Course of the activities involved. The results indicated that cortical activities were recorded around SI, contralateral secondary somatosensory cortex (611), ipsilateral secondary somatosensory cortex (iSII), and PPC between 150-185 ms. The precise location of PPC was indicated to be the inferior parietal lobule (IPL), corresponding to Brodmann's area 40. The mean peak latencies of SI, cSII, iSII and IPL were 152, 170, 181, and 183 ms, respectively. This is the first study to clarify the time course of the activities of SI, SII, and PPC in human pain processing using MEG. (C) 2008 Elsevier Inc. All rights reserved., 2008, 42, 858, 868, 10.1016/j.neuroimage.2008.05.017

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• Refereed, NeuroImage, ACADEMIC PRESS INC ELSEVIER SCIENCE, Somato-motor inhibitory processing in humans: An event-related functional MRI study., Nakata H, Sakamoto K, Ferretti A, Perrucci GM, Del Gratta C, Kakigi R, Romani GL, Inhibiting inappropriate behavior and thoughts is an essential ability for humans, but the regions responsible for inhibitory processing are a matter of continuous debate. This is the first study of somatosensory go/nogo tasks using event-related functional magnetic resonance imaging (fMRI). Fifteen subjects preformed two different types of go/nogo task, i.e. (1) Movement and (2) Count, to compare with previous studies using visual go/nogo tasks, and confirm whether the inhibitory processing is dependent on sensory modalities. Go and nogo stimuli were presented with an even probability. Our data indicated that the response inhibition network involved the dorsolateral (DLPFC) and ventrolateral (VLPFC) prefrontal cortices, pre-supplementary motor area (pre-SMA), anterior cingulate cortex (ACC), inferior parietal lobule (IPL), insula, and temporoparietal junction (TPJ), which were consistent with previous results obtained using visual go/nogo tasks. These activities existed in both Movement and Count Nogo trials. Therefore, our results suggest that the network for inhibitory processing is not dependent on sensory modalities but reflects common neural activities. In addition, there were differences of activation intensity between Movement and Count Nogo trials in the prefrontal cortex, temporal lobe, and ACC. Thus, inhibitory processing would involve two neural networks, common and uncommon regions, depending on the required response mode. (c) 2007 Elsevier Inc. All rights reserved., 2008, 39, 1858, 1866, Scientific journal, 10.1016/j.neuroimage.2007.10.041

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• Refereed, Clin Neurophysiol, ELSEVIER IRELAND LTD, Objective examination for two-point stimulation using a somatosensory oddball paradigm: an MEG study., Akatsuka K, Wasaka T, Nakata H, Kida T, Hoshiyama M, Tamura Y, Kakigi R, Objective: To establish an objective two-point discrimination test using magnetoencephalography (MEG). Methods: First, we determined the discrimination threshold (DT) of the two-points. In the first experiment, we applied 0.9DT as standard stimuli, and 0.8DT, 1.1DT and 2DT as deviant stimuli in Conditions 1, 2 and 3, respectively. In the second experiment, we used 2DT and 0.9DT as the standard and deviant stimuli, respectively, in Condition 1. We applied two-stimuli that subjects felt as definitely one point or two-points in Condition 2 and 3, respectively. Results: In the first experiment, the components peaking around 30-70 and 150-250 ms following deviant stimuli were significantly larger than those following standard stimuli. Considering the peak latency, these components seem consistent with the magnetic mismatch field (MMF). In the second experiment, the MMF was recorded only in Condition 1. Therefore, it is considered that the MMF was recorded only when subjects automatically discriminate one point from two-points stimuli. Conclusions: This novel method can be used in neurophysiological two-point discrimination tests without the need to rely on the examiners' skills and subjects' reactions. Significance: We confirmed that our new method could be used for the objective examination of two-point spatial discrimination. (c) 2006 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., 2007, 118, 403, 411, Scientific journal, 10.1016/j.clinph.2006.09.030

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• Refereed, Exp Brain Res, SPRINGER, The effect of stimulus probability on the somatosensory mismatch field., Akatsuka K, Wasaka T, Nakata H, Kida T, Kakigi R, We investigated the effect of deviant stimulus probability on the somatosensory magnetic mismatch negativity (MMNm) using an electrical two-point stimulation. First, we determined the discrimination threshold (DT) of the two-point distance. We applied standard stimuli at a distance that subjects felt as one point and deviant stimuli at a distance that subjects definitely felt as two points. We used three deviant stimulus probabilities, 10, 30, and 50%. The components peaking around 30-70 ms (first component) and 150-250 ms (fourth component) following deviant stimuli were significantly larger than those following standard stimuli in 10% condition, but not in 30 or 50% condition. The equivalent current dipole (ECD) was located in the contralateral primary somatosensory cortex (cSI) for the first component, and in the cSI and in the contralateral secondary somatosensory cortex (cSII) for the fourth component. The peak amplitude of the MMNm decreased as the probability of the deviant stimulus increased. The Somatosensory MMNm was affected by deviant stimulus probability similar to an auditory mismatch negativity (MMN)., 2007, 181, 607, 614, Scientific journal, 10.1007/s00221-007-0958-4

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• Refereed, Neuroscience, PERGAMON-ELSEVIER SCIENCE LTD, Characteristics of sensori-motor interaction in the primary and secondary somatosensory cortices in humans: A magnetoencephalography study., Wasaka T, Kida T, Nakata H, Akatsuka K, Kakigi R, We studied sensori-motor interaction in the primary (SI) and secondary somatosensory cortex (Sill using magnetoencephalography. Since SII in both hemispheres was activated following unilateral stimulation, we analyzed SIIc (contralateral to stimulation) as well as SIIi (ipsilateral to stimulation). Four tasks were performed in human subjects in which a voluntary thumb movement of the left or right hand was combined with electrical stimulation applied to the index finger of the left or right hand: L-M-L-(S) (movement of the left thumb triggered stimulation to the left finger), L-(M)-R((S)) (movement of the left thumb triggered electrical stimulation to the right finger), R-(M)-R-(S) (movement of the right thumb triggered electrical stimulation to the right finger), and R-(M)-L-(S) (movement of the right thumb triggered electrical stimulation to the left finger). Stimulation to the index finger only (S condition) was also recorded. In SI, the amplitude of N20m and P35m was significantly attenuated in the R-(M)-R-(S) and L-(M)-L-(S) tasks compared with the S condition, but that for other tasks showed no change, corresponding to a conventional gating phenomenon. In SII, the R-(M)-L-(S) task significantly enhanced the amplitude of SIIc but reduced that of SIIi compared with the S condition. The L-(M)-L-(S) and R-(M)-R-(S) tasks caused a significant enhancement only in Sill. The L-(M)-R-(S) task enhanced the amplitude only in SIIc. The laterality index showed that SII modulation with voluntary movement was more dominant in the hemisphere ipsilateral to movement but was not affected by the side of stimulation. These results provided the characteristics of activities in somatosensory cortices, a simple inhibition in SI but complicated changes in SII depending on the side of movement and stimulation, which may indicate the higher cognitive processing in SII. (C) 2007 IBRO. Published by Elsevier Ltd. All rights reserved., 2007, 149, 446, 456, Scientific journal, 10.1016/j.neuroscience.2007.07.040

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• Refereed, NeuroImage, ACADEMIC PRESS INC ELSEVIER SCIENCE, Centrifugal regulation of human cortical responses to a task-relevant somatosensory signal triggering voluntary movement., Kida T, Wasaka T, Inui K, Akatsuka K, Nakata H, Kakigi R, Many studies have reported a movement-related modulation of response in the primary and secondary somatosensory cortices (SI and Sit) to a task-irrelevant stimulation in primates. In the present study, magnetoencephalography (MEG) was used to examine the top-down centrifugal regulation of neural responses in the human SI and Sit to a task-relevant somatosensory signal triggering a voluntary movement. Nine healthy adults participated in the study. A visual warning signal was followed 2 s later by a somatosensory imperative signal delivered to the right median nerve at the wrist. Three kinds of warning signal informed the participants of the reaction which should be executed on presentation of the imperative signal (rest or extension of the right index finger, extension of the left index ringer). The somatosensory stimulation was used to both generate neural responses and trigger voluntary movement and therefore was regarded as a task-relevant signal. The responses were recorded using a whole-head MEG system. The P35m response around the SI was reduced in magnitude without alteration of the primary SI response, N20m, when the signal triggered a voluntary movement compared to the control condition, whereas bilateral SII responses peaking at 70-100 ms were enhanced and the peak latency was shortened. The peak latency of the responses in the SI and Sit preceded the onset of the earliest voluntary muscle activation in each subject. Later bilateral perisylvian responses were also enhanced with movement. In conclusion, neural activities in the SI and Sit evoked by task-relevant somatosensory signals are regulated differently by motor-related neural activities before the afferent inputs. The present findings indicate a difference in function between the SI and Sit in somatosensory-motor regulation. (c) 2006 Elsevier Inc. All rights reserved., 2006, 32, 1355, 1364, Scientific journal, 10.1016/j.neuroimage.2006.05.015

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• Refereed, Suppl Clin Neurophysiol, Cortical processing of noxious information in humans: a magnetoencephalographic study., Inui K, Wang X, Qiu Y, Tsuji T, Nakata H, Kakigi R, 2006, 59, 127, 1331
• Refereed, Cereb Cortex, OXFORD UNIV PRESS INC, Brain processing of the signals ascending through unmyelinated C fibers in humans: an event-related fMRI study., Qiu Y, Honda M, Noguchi Y, Nakata H, Tamura Y, Tanaka S, Sadato N, Wang X, Inui K, Kakigi R, Event-related functional magnetic resonance imaging was used to investigate brain processing of the signals ascending from peripheral C and A delta fibers evoked by phasic laser stimuli on the right hand in humans. The stimulation of both C and A delta nociceptors activated the bilateral thalamus, bilateral secondary somatosensory cortex, right (ipsilateral) middle insula, and bilateral Brodmann's area (BA) 24/32, with the majority of activity found in the posterior portion of the anterior cingulate cortex (ACC). However, magnitude of activity in the right (ipsilateral) BA32/8/6, including dorsal parts in the anterior portion of the ACC (aACC) and pre-supplementary motor area (pre-SMA), and the bilateral anterior insula was significantly stronger following the stimulation of C nociceptors than A delta nociceptors. It was concluded that the activation of C nociceptors, related to second pain, evokes different brain processing from that of A delta nociceptors, related to first pain, probably due to the differences in the emotional and motivational aspects of either pain, which are mainly related to the aACC, pre-SMA, and anterior insula., 2006, 16, 1289, 1295, Scientific journal, 10.1093/cercor/bhj071

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• Refereed, Exp Brain Res, SPRINGER, Centrifugal regulation of task-relevant somatosensory signals to trigger a voluntary movement., Kida T, Wasaka T, Nakata H, Kakigi R, Many previous papers have reported the modulation of somatosensory evoked potentials (SEPs) during voluntary movement, but the locus and mechanism underlying the movement-induced centrifugal modulation of the SEPs elicited by a task-relevant somatosensory stimulus still remain unclear. We investigated the centrifugal modulation of the SEPs elicited by a task-relevant somatosensory stimulus which triggers a voluntary movement in a forewarned reaction time task. A pair of warning (S1: auditory) and imperative stimuli (S2: somatosensory) was presented with a 1 s interstimulus interval. Subjects were instructed to respond by moving the hand ipsilateral or contralateral to the somatosensory stimulation which elicits the SEPs. In four experiments, the locus and selectivity of the SEPs' modulation, the contribution of cutaneous afferents and the effect of contraction magnitude were examined, respectively. A control condition where subjects had no task to perform was compared to several task conditions. The amplitude of the frontal N30, parietal P30, and central P25 was decreased and that of the long latency P80 and N140 was increased when the somatosensory stimuli triggered a voluntary movement of the stimulated finger compared to the control condition. The N60 decreased with the movement of any finger. These results were considered to be caused by the centrifugal influence of neuronal activity which occurs before a somatosensory imperative stimulus. The present findings did not support the hypothesis that the inhibition of afferent inputs by descending motor commands can occur at subcortical levels. A higher contraction magnitude produced a further attenuation of the amplitude of the frontal N30, while it decreased the enhancement of the P80. Moreover, the modulation of neuronal responses seems to result mainly from the modulation of cutaneous afferents, especially from the moved body parts. In conclusion, the short- and long-latency somatosensory neuronal activities evoked by task-relevant ascending afferents from the moved body parts are regulated differently by motor-related neuronal activities before those afferent inputs. The latter activities may be associated with sensory gain regulation related to directing attention to body parts involved in the action., 2006, 169, 289, 301, Scientific journal, 10.1007/s00221-005-0141-8

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• Refereed, Exp Brain Res, SPRINGER, Centrifugal regulation of a task-relevant somatosensory signal triggering voluntary movement without a preceding warning signal., Kida T, Wasaka T, Nakata H, Akatsuka K, Kakigi R, A warning signal followed by an imperative signal generates anticipatory and preparatory activities, which regulate sensory evoked neuronal activities through a top-down centrifugal mechanism. The present study investigated the centrifugal regulation of neuronal responses evoked by a task-relevant somatosensory signal, which triggers a voluntary movement without a warning signal. Eleven healthy adults participated in this study. Electrical stimulation was delivered to the right median nerve at a random interstimulus interval (1.75-2.25 s). The participants were instructed to extend the second digit of the right hand as fast as possible when the electrical stimulus was presented (ipsilateral reaction condition), or extend that of the left hand (contralateral reaction condition). They also executed repetitively extension of the right second digit at a rate of about 0.5 Hz, irrespective of electrical stimulation (movement condition), to count silently the number of stimuli (counting condition). In the control condition, they had no task to perform. The amplitude of short-latency somatosensory evoked potentials, the central P25, frontal N30, and parietal P30, was significantly reduced in both movement and ipsilateral reaction conditions compared to the control condition. The amplitude of long-latency P80 was significantly enhanced only in the ipsilateral reaction condition compared to the control, movement, contralateral reaction, and counting conditions. The long-latency N140 was significantly enhanced in both movement and ipsilateral reaction conditions compared to the control condition. In conclusion, short- and long-latency neuronal activities evoked by task-relevant somatosensory signals were regulated differently through a centrifugal mechanism even when the signal triggered a voluntary movement without a warning signal. The facilitation of activities at a latency of around 80 ms is associated with gain enhancement of the task-relevant signals from the body part involved in the action, whereas that at a latency of around 140 ms is associated with unspecific gain regulation generally induced by voluntary movement. These may be dissociated from the simple effect of directing attention to the stimulation., 2006, 173, 733, 741, Scientific journal, 10.1007/s00221-006-0448-0

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• Refereed, Exp Brain Res, SPRINGER, Active attention modulates passive attention-related neural responses to sudden somatosensory input against a silent background., Kida T, Wasaka T, Nakata H, Akatsuka K, Kakigi R, To reveal whether active attention modulates neuronal responses related to passive attention to somatosensory stimuli presented suddenly against a silent background, we examined the passive attention-related change in amplitude of the event-related brain potentials (ERPs), caused by temporal infrequency of stimuli. Eighteen healthy subjects performed passive and active attention tasks in two stimulus conditions. In the oddball condition, frequent (80%, standard) and infrequent (20%, deviant) electrical stimuli were randomly delivered to the second and third digits of the left hand. In the deviant-alone condition, the deviant stimulus (deviant-alone stimulus) was delivered with the same timing and sequence as in the oddball condition without standard stimuli. The P100, N140, and P200 elicited by the deviant-alone stimulus were enhanced in amplitude compared to those evoked by the oddball deviant stimulus in both the active and passive tasks. Moreover, active attention increased the enhancement of P100 and N140. The difference waveform (deviant-alone minus oddball deviant) provided similar findings. In conclusion, active attention enhances neural responses related to passive shifts of attention to somatosensory signals suddenly presented against a silent background. The results indicate that top-down signals for detecting target stimuli interact with passive shifts of attention caused by bottom-up signals., 2006, 175, 609, 617, Scientific journal, 10.1007/s00221-006-0578-4

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• Refereed, Clin Neurophysiol, ELSEVIER IRELAND LTD, Pre-movement modulation of tibial nerve SEPs caused by a self-initiated dorsiflexion., Wasaka T, Nakata H, Kida T, Kakigi R, Objective: To investigate the centrifugal effect on somatosensory evoked potentials (SEPs), we recorded the pre-movement modulation of SEPs following stimulation of the tibial nerve caused by a self-initiated dorsiflexion. Methods: SEPs following stimulation of the right tibial nerve at the popliteal fossa were recorded during self-initiated dorsiflexion of the right ankle every 5-7 s. Based on the onset of Bereitschaftspotential and negative slope, the preparatory period before dorsiflexion was divided into four sub-periods (pre-BP, BP1a, BP1b and BP2 sub-period), and SEPs in each sub-period were averaged. SEPs were also recorded in a stationary condition. Results: P30, N40, P50 and N70 were identified at Cz in all subjects. The amplitude of P30 was significantly smaller in the BP2 sub-period than in the pre-BP sub-period. The N40 amplitude was significantly attenuated in the BP2 sub-period compared with the stationary condition, the pre-BP sub-period, the BP1a sub-period and the BPlb sub-period. Conclusions: These results suggested that the motor-related areas involved in generating negative slope modulated the tibial nerve SEPs preceding a self-initiated contraction of the agonist muscle. Significance: The centrifugal gating effect on SEPs extends to the somatosensory information from the antagonistic body part. (c) 2006 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., 2006, 117, 2023, 2029, Scientific journal, 10.1016/j.clinph.2006.06.003

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• Refereed, Neurosci Lett, ELSEVIER IRELAND LTD, The characteristics of the nogo-N140 component in somatosensory go/nogo tasks., Nakata H, Inui K, Wasaka T, Tamura Y, Kida T, Kakigi R, Nogo-related brain potentials may not be dependent on sensory modalities but reflect common neural activities specific to the inhibitory process. Recent studies reported that nogo potentials were elicited by not only visual and auditory but also somatosensory stimulation. However, the characteristics of this nogo potential evoked by somatosensory stimulation have been unclear because of the small number of reports. In the present study, therefore, to determine the characteristics of this potential, the effects of stimulus site and response hand were investigated. Electrical stimulation was delivered to the second and fifth digit of one hand, and the subjects had to respond to a go stimulus by pushing a button with the thumb contralateral to the stimulated side as quickly as possible. The amplitudes of the nogo-N140 component (N140 evoked by the nogo stimuli), which is very similar to the nogo-N2 components following visual and auditory stimulation, were unrelated to the stimulated digits, the second and fifth digit of the left and right hand. However, differences between go and nogo ERPs were significantly larger in the hemisphere contralateral to the response hand than the ipsilateral hemisphere. This result was inconsistent with visual and auditory go/nogo studies showing a right-hemi sphere dominance or bilateral activities in nogo trials. Therefore, nogo-N140 should be considered to reflect the inhibitory process especially in the hemisphere contralateral to the response hand and the sensory modality dependency of nogo potentials. (c) 2006 Elsevier Ireland Ltd. All rights reserved., 2006, 397, 318, 322, Scientific journal, 10.1016/j.neulet.2005.12.041

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• Refereed, Clin Neurophysiol, ELSEVIER IRELAND LTD, Higher anticipated force required a stronger inhibitory process in go/nogo tasks., Nakata H, Inui K, Wasaka T, Tamura Y, Akatsuka K, Kida T, Kakigi R, Objective: We investigated the effect of the inhibitory process with increasing muscle force on event-related potentials (ERPs) and motor evoked potentials (MEPs). Methods: The subjects performed a S1-S2 paradigm with go/nogo tasks. S1 was an auditory tone burst, and S2 was an electrical stimulation applied to the second (go stimuli) or fifth digit (nogo stimuli) of the left hand. The recordings were conducted at 3 force levels; 10, 30 and 50% maximal voluntary contraction (MVC). After the presentation of S2, the subjects were instructed to adjust their force level to match the target line with a force trajectory line in only the go trials. Results: Nogo-N 140 was significantly more negative in amplitude than go-N140 in all conditions, and became larger with increasing muscle force. The MEP, which was recorded at 150 ms after S2, became significantly smaller with increasing muscle force in nogo trials, whereas it became larger in go trials. Conclusions: Our results indicated that stronger inhibitory cerebral activity was needed for a nogo stimulus, in the case where a stronger response was needed for a go stimulus. Significance: The present study showed a significant relationship between cortical inhibitory process and muscle force. (c) 2006 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., 2006, 117, 1669, 1676, Scientific journal, 10.1016/j.clinph.2006.03.032

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• Not Refereed, PAIN RESEARCH, C線維を上行する信号によって賦活される脳部位：機能的磁気共鳴画像(fMRI)を用いた研究, Nakata Hiroki, 2006, 21, 95-102
• Refereed, Eur J Neurosci, BLACKWELL PUBLISHING, Functional relationship between human rolandic oscillations and motor cortical excitability: an MEG study., Tamura Y, Hoshiyama M, Nakata H, Hiroe N, Inui K, Kaneoke Y, Inoue K, Kakigi R, Synchronization and desynchronization of the neural rhythm in the brain play an important role in the orchestration of perception, motor action and conscious experience. Based on the results of electrocorticographic and magnetoencephalographic (MEG) recordings, it has been considered that human rolandic oscillations originate in the anterior bank of the central sulcus (20-Hz rhythm) and the postcentral cortex (10-Hz rhythm): the 20-Hz oscillation is closely related to motor function, while the 10-Hz rhythm is attributed mainly to sensory function. To test whether the rolandic oscillations are functionally relevant to the motor cortical excitability, we examined effects of 1-Hz repetitive transcranial magnetic stimulation (rTMS) of the left primary motor cortex (M1) on movement-related changes of the rolandic oscillations in 12 normal subjects. MEG data recorded during brisk extension of the right index finger in two different sessions (with and without rTMS conditioning) were compared. Motor-evoked potential (MEP) of the right hand muscle was also measured before and after rTMS to assess the motor cortical excitability. We found that 1-Hz rTMS over M1 significantly reduced the movement-related rebound of the 20-Hz oscillation in association with decreased motor cortical excitability. In particular, movement-related rebound of the 20-Hz rhythm was closely tied with motor cortical excitability. These findings further strengthen the notion of functional relevance of 20-Hz cortical oscillation to motor cortical excitability. In the framework of previous studies, the decrease in movement-related rebound may be regarded as a compensatory reaction to the inhibited cortical activity., 2005, 21, 2555, 2562, Scientific journal, 10.1111/j.1460-9568.2005.04096.x

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• Refereed, Clin Neurophysiol, ELSEVIER IRELAND LTD, Mismatch responses related to temporal discrimination of somatosensory stimulation., Akatsuka K, Wasaka T, Nakata H, Inui K, Hoshiyama M, Kakigi R, Objective: To determine the existence of a preattentively evoked somatosensory mismatch negativity component and to investigate the use of that component in objective clinical diagnostics. Methods: First we determined the temporal discrimination threshold (DT) of paired stimuli in each subject, and applied two sequential electrical stimuli to the hand with paired stimulus times of (1) DT -10 ms, (2) DT -30 ms and (3) DT +50 ms. Then, we recorded ERPs using an oddball paradigm, frequent (standard) and rare (deviant). We used two stimuli, DT-30 ms and DT-10 ms, in the first experiment, and DT -30 ms and DT +50 ms, in the second experiment. Results: In each experiment, two specific components, a negative component peaking at approximately 60 ms (N60) and a large positive component peaking around 100-200 ms (P150), were identified, mainly following the deviant stimulus, which were considered somatosensory mismatch components. N60 was more remarkably identified in the second experiment and P150 in the first. Conclusions: N60 might be generated during tasks which subjects can clearly discriminate, but P150, which seems to correspond to auditory mismatch negativity, might be generated in tasks which require fine discrimination. Significance: We confirmed that our new method could be used for the objective examination of temporal discrimination. (c) 2005 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., 2005, 116, 1930, 1937, Scientific journal, 10.1016/j.clinph.2005.04.021

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• Refereed, Clin Neurophysiol, ELSEVIER IRELAND LTD, Face representation in the human secondary somatosensory cortex., Nguyen BT, Inui K, Hoshiyama M, Nakata H, Kakigi R, Objective: To investigate the somatotopic organization of the facial skin area in the secondary somatosensory cortex (SII) in humans. Methods: Somatosensory evoked magnetic fields following air-puff stimulation of 5 body sites, the foot, the lip and 3 points of the facial skin (forehead. cheek and mandibular angle point), were recorded. We focused on activities in SII following stimulation of these 5 sites and compared dipole locations among them. Results: There was a clear somatotopic organization in SII with lip in the most lateral area, foot in the most medial area and face in an intermediate area close to the lip area. However, there was no significant difference of dipole localization in Sit among the 3 areas of facial skin. similar to the overlapped somatotopic organization of facial skin areas in the primary somatosensory cortex in our previous study. Conclusions: The facial skin areas are considered to occupy a small area in SII with insufficient spatial separation to differentiate each area of facial skin even using magnetoencephalography which has a high spatial resolution. Significance: This is the first systematic study of the activated regions in SII following stimulation of the facial skin. (c) 2005 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., 2005, 116, 1247, 1253, Scientific journal, 10.1016/j.clinph.2005.01.018

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• Refereed, Eur J Pain, W B SAUNDERS CO LTD, Intracerebral pain processing in a Yoga Master who claims not to feel pain during meditation., Kakigi R, Nakata H, Inui K, Hiroe N, Nagata O, Honda M, Tanaka S, Sadato N, Kawakami M., We recorded magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) following noxious laser stimulation in a Yoga Master who claims not to feel pain when meditating. As for background MEG activity, the power of alpha frequency bands peaking at around 10 Hz was much increased during meditation over occipital, parietal and temporal regions, when compared with the non-meditative state, which might mean the subject was very relaxed, though he did not fall asleep, during meditation. Primary pain-related cortical activities recorded from primary (SI) and secondary somatosensory cortices (SII) by MEG were very weak or absent during meditation. As for fMRI recording, there were remarkable changes in levels of activity in the thalamus, SII-insula (mainly the insula) and cingulate cortex between meditation and non-meditation. Activities in all three regions were increased during non-meditation, similar to results in normal subjects. In contrast, activities in all three regions were weaker during meditation, and the level was lower than the baseline in the thalamus. Recent neuroirnaging and electrophysiological studies have clarified that the emotional aspect of pain perception mainly involves the insula and cingulate cortex. Though we cannot clearly explain this unusual condition in the Yoga Master, a change of multiple regions relating to pain perception could be responsible, since pain is a complex sensory and emotional experience. (c) 2004 European Federation of Chapters of the International Association for the Study of Pain. Published by Elsevier Ltd. All rights reserved., 2005, 9, 581, 589, Scientific journal, 10.1016/j.ejpain.2004.12.006

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• Refereed, Brain Res Cogn Brain Res, ELSEVIER SCIENCE BV, Gating of SEPs by contraction of the contralateral homologous muscle during the preparatory period of self-initiated plantar flexion., Wasaka T, Nakata H, Kida T, Kakigi R, To investigate the centrifugal change in somatosensory information processing caused by contraction of the contralateral homologous muscle, we recorded the somatosensory-evoked potentials (SEPs) during the preparatory period of a self-initiated plantar flexion. The SEPs following stimulation of the right tibial nerve at the popliteal fossa were recorded in nine healthy subjects. Self-initiated plantar flexion of the left ankle was performed once every 5 to 7 s. The electrical stimulation was delivered continuously, and the subjects were instructed to concentrate on the movement and not to pay attention to the electrical stimulation. Based on the components of movement-related cortical potential, Bereitschaftspotential (BP) and Negative slope (NS), the preparatory period was divided into four sub-periods (NS, BP-1, BP-2, and Pre-BP). To obtain pre-movement SEPs, the signals following stimulation in each sub-period were averaged. SEPs were attenuated in the preparatory period, especially in the NS sub-period. The amplitude of N40 component was significantly attenuated compared with that in the stationary state and other sub-periods. The amplitude of P53 and N70 was smaller in the NS sub-period than other pre-movement subperiods. Since there was no centripetal effect on SEPs in the preparatory period, these findings suggested that the activity of motor-related areas modulated the somatosensory information from the contralateral non-movement limb (centrifugal gating). It was assumed that an inhibition on the somatosensory inputs from contralateral limb was caused by the projection via either the corpus callosum or ipsilateral cortico-cortical projections. (c) 2004 Elsevier B.V. All rights reserved., 2005, 23, 354, 360, Scientific journal, 10.1016/j.cogbrainres.2004.11.002

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• Refereed, Exp Brain Res, SPRINGER, Changes in the centrifugal gating effect on somatosensory evoked potentials depending on the level of contractile force., Wasaka T, Nakata H, Kakigi R, Kida T., In this study, we investigated the somatosensory evoked potentials (SEPs) during the preparatory period of self-initiated plantar flexion at different force levels of muscle contraction and elucidated the mechanism behind the centrifugal gating effect on somatosensory information processing. We recorded SEPs following stimulation of the tibial nerve at the popliteal fossa during the preparatory period of a 20% maximal voluntary contraction (MVC) and 50% MVC. The preparatory period was divided into two sub-periods based on the components of movement-related cortical potentials, the negative slope (NS sub-period) and the Bereitschaftspotential (BP sub-period). The subjects were instructed to concentrate on the movement and not to pay attention to the continuous electrical stimulation. Pre-movement SEPs were averaged separately during the two sub-periods under each MVC condition. The mean amplitudes of BP and NS were larger during the 50% MVC than the 20% MVC. As for the components of SEPs, during the NS sub-period the amplitude of P30 under the 50% MVC and N40 under both conditions were significantly smaller than that in the stationary sequence, and N40 amplitude was significantly smaller during the 50% MVC than the 20% MVC. During the BP sub-period, the amplitude of P30 and N40 during the 50% MVC was significantly smaller than during the stationary sequence, while it was not significantly different between the 20% and 50% MVCs. In conclusion, the extent of the centrifugal gating effect on SEPs was dependent on the activities of motor-related areas, which generated the NS and BP., 2005, 166, 118, 125, Scientific journal, 10.1007/s00221-005-2333-7

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• Refereed, Eur J Neurosci, BLACKWELL PUBLISHING, Differential modulation in human primary and secondary somatosensory cortices during the preparatory period of self-initiated finger movement., Wasaka T, Nakata H, Akatsuka K, Kida T, Inui K, Kakigi R., To elucidate the mechanisms underlying sensorimotor integration, we investigated modulation in the primary (SI) and secondary (SII) somatosensory cortices during the preparatory period of a self-initiated finger extension. Electrical stimulation of the right median nerve was applied continuously, while the subjects performed a self-initiated finger extension and were instructed not to pay attention to the stimulation. The preparatory period was divided into five sub-periods from the onset of the electromyogram to 3000 ms before movement and the magnetoencephalogram signals following stimulation in each sub-period were averaged. Multiple source analysis indicated that the equivalent current dipoles (ECDs) were located in SI and bilateral SII. Although the ECD moment for N20m (the upward deflection peaking at around 20 ms) was not significantly changed, that for P30m (the downward deflection peaking at around 30 m) was significantly smaller in the 0- to -500-ms sub-period than the -2000- to -3000-ms sub-period. As for SII, the ECD moment for the SII ipsilateral to movement showed no significant change, while that for the contralateral SII was significantly larger in the 0- to -500-ms sub-period than the -1500- to -2000-ms or -2000- to -3000-ms sub-period. The opposite effects of movement on SI and SII cortices indicated that these cortical areas play a different role in the function of the sensorimotor integration and are affected differently by the centrifugal process., 2005, 22, 1239, 1247, Scientific journal, 10.1111/j.1460-9568.2005.04289.x

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• Refereed, J Cogn Neurosci, M I T PRESS, An ERP study of second language learning after childhood: Effects of proficiency., Ojima S, Nakata H, Kakigi R, Whether there is an absolute critical period for acquiring language is a matter of continuous debate. One approach to address this issue is to compare the processes of second language (L2) learning after childhood and those of first language (L1) learning during childhood. To study the cortical process of postchildhood L2 learning, we compared event-related brain potentials recorded from two groups of adult Japanese speakers who attained either high or intermediate proficiency in English after childhood (J-High and J-Low), and adult native English speakers (ENG). Semantic anomalies embedded in English sentences evoked a clear N400 component in all three groups, With only the time Course of the brain activation varying among the groups. Syntactic violations elicited a left-lateralized negativity similar to the left anterior negativity in ENG and J-High, but not in J-Low. In ENG, a P600 component was additionally found. These results suggest that semantic processing is robust from early on in L2 learning, whereas the development of syntactic processing is more dependent on proficiency as evidenced by the lack of the left-lateralized negativity in J-Low. Because early maturation and stability of semantic processing as opposed to syntactic processing are also a feature of L1 processing, postchildhood L2 learning may be governed by the same brain properties as those which govern childhood L1 learning. We argue that these processes are qualitatively similar in many respects, with only restricted domains of language processing being subject to absolute critical period effects., 2005, 17, 1212, 1228, Scientific journal
• Refereed, Exp Brain Res, SPRINGER, Effects of ISI and stimulus probability on event-related go/nogo potentials after somatosensory stimulation., Nakata H, Inui K, Wasaka T, Tamura Y, Kida T, Kakigi R, The present study investigated the characteristics of the middle-latency negative potential of event-related potentials (ERPs) using somatosensory go/nogo tasks. We manipulated interstimulus interval (ISI) in Experiment 1 and stimulus probability in Experiment 2 and analyzed the subtracted difference waveform resulting from subtraction of the ERP evoked by the go stimulation from that evoked by the nogo stimulation. In Experiment 1, the peak latency of negativity became significantly longer as the ISI increased, but the peak amplitude was unchanged. The reaction time (RT) was longer with increasing ISI. In Experiment 2, manipulation of the stimulus probability yielded an increase in peak amplitude with decreasing probability of the nogo stimulus, but did not affect the latency. The RT increased as the probability of a nogo stimulus rose. Because manipulation of the ISI and stimulus probability elicited different brain activities, we hypothesized that manipulation of the ISI elicited a delay of the stimulus evaluation process including response inhibition, and that stimulus probability significantly affected the strength of the response inhibition process., 2005, 162, 293, 299, Scientific journal, 10.1007/s00221-004-2195-4

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• Refereed, Eur J Neurosci, BLACKWELL PUBLISHING, Somato-motor inhibitory processing in humans: A study with MEG and ERP., Nakata H, Inui K, Wasaka T, Akatsuka K, Kakigi R., The go/nogo task is a useful paradigm for recording event-related potentials (ERPs) to investigate the neural mechanisms of response inhibition. In nogo trials, a negative deflection at around 140-300 ms (N2), which has been called the 'nogo potential', is elicited at the frontocentral electrodes, compared with ERPs recorded in go trials. In the present study, we investigated the generators of nogo potentials by recording ERPs and by using magnetoencephalography (MEG) simultaneously during somatosensory go/nogo tasks to elucidate the regions involved in generating nogo potentials. ERP data revealed that the amplitude of the nogo-N140 component, which peaked at about 155 ms from frontocentral electrodes, was significantly more negative than that of go-N140. MEG data revealed that a long-latency response peaking at approximately 160 ms, termed nogo-M140 and corresponding to nogo-N140, was recorded in only nogo trials. The equivalent current dipole of nogo-M140 was estimated to lie around the posterior part of the inferior frontal sulci in the prefrontal cortex. These results revealed that both nogo-N140 and nogo-M140 evoked by somatosensory go/nogo tasks were related to the neural activity generated from the prefrontal cortex. Our findings combining MEG and ERPs clarified the spatial and temporal processing related to somato-motor inhibition caused in the posterior part of the inferior frontal sulci in the prefrontal cortex in humans., 2005, 22, 1784, 1792, Scientific journal, 10.1111/j.1460-9568.2005.04368.x

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• Refereed, Brain Res, ELSEVIER SCIENCE BV, Load- and cadence-dependent modulation of somatosensory evoked potentials and Soleus H-reflexes during active leg pedaling in humans., Sakamoto M, Nakajima T, Wasaka T, Kida T, Nakata H, Endoh T, Nishihira Y, Komiyama T, Modulation of transmission in group I muscle afferent pathways to the somatosensory cortex and those to the a-motoneuron were investigated during active leg pedaling. Cerebral somatosensory evoked potentials (SEPs) and Soleus (Sol) H-reflexes following posterior tibial nerve stimulation were recorded at four different pedaling phases. The subjects were asked to perform pedaling at three different cadences (30, 45 and 60 rpm with 0.5 kp, cadence task; C-task) and with three different workloads (at 45 rpm with 0.0, 0.5 and 1.0 kp, load task: L-task). In both C- and L-tasks, Sol H-reflexes were modulated in a phase-dependent manner, showing an increase in the power phase and a decrease in the recovery phase. In contrast, the early SEP (P30-N40) components were modulated in a phase-dependent manner when the cadence and load were low. When focusing on the power phases, significant cadence- and load-dependent modulations of the P30-N40 were found, and inversely graded with the cadence and load. The H-reflex was found to be significantly decreased at the highest cadence, i.e., cadence-dependent modulation. In contrast, the H-reflex during the L-task was found to be proportional to the load. The correlation analysis between the size of H-reflex and the amount of background (BG) electromyographic (EMG) activity demonstrated that the H-reflex in the power phase did not depend on the BG EMG in either C- or L-task. These findings suggested that transmission of muscle afferents along the ascending pathways to the cerebral cortex and the spinal cord is independently controlled in accordance with the biomechanical constraints of active pedaling. (C) 2004 Elsevier B.V. All rights reserved., 2004, 1029, 272, 285, Scientific journal, 10.1016/j.brainres.2004.09.054

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• Refereed, Brain Res Cogn Brain Res, ELSEVIER SCIENCE BV, Differential modulation of temporal and frontal components of the somatosensory N140 and the effect of interstimulus interval in a selective attention task., Kida T, Nishihira Y, Wasaka T, Nakata H, Sakamoto M, modulation of the somatosensory N140 was examined in a selective attention task where a control condition was applied and the interstimulus interval (ISI) was varied. Electrical stimuli were randomly presented to the left index (p = 0.4) and middle fingers (p = 0.1), and right index (p = 0.4) and middle fingers (p = 0.1). In the attend-right condition, subjects were instructed to count silently the number of infrequent target stimuli presented to the right middle finger, and to the left middle finger in the attend-left condition. They had no task in the control condition. Each condition was performed with two different sets of ISI (mean 400 vs. 800 ms). The somatosensory N140 elicited by frequent standard stimuli was analyzed. The N140 amplitude was larger for the attended ERP compared to the control and unattended ERPs. This attention effect was more marked at the frontal electrodes compared to the temporal electrodes contralateral to the stimulation side. Furthermore, the attention effect at the frontal electrode was larger when the ISI was 800 ms than when it was 400 ms. The N140 amplitude did not differ between the control and unattended ERPs, which might show that a small processing negativity (PN) occurred during the control condition or difference in vigilance level between them. In conclusion, the early lateral ("temporal") and late midline ("frontal") components of the N1 (N140) show different behavior, and thus may have different functional significance. Enhancement of the attention effect at the frontal electrode in the longer ISI condition supports the hypothesis that it is related to stronger, voluntary maintenance of the attentional trace. (C) 2003 Elsevier B.V. All rights reserved., 2004, 19, 33, 39, Scientific journal, 10.1016/j.cogbrainres.2003.10.016

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• Refereed, Clin Neurophysiol, ELSEVIER SCI IRELAND LTD, Passive enhancement of the somatosensory P100 and N140 in an active attention task using deviant alone condition., Kida T, Nishihira Y, Wasaka T, Nakata H, Sakamoto M, Objective: We investigated the changes in the somatosensory P100 and N140 during passive (reading) versus active tasks (counting, button pressing) and oddball (target = 20%, standard = 80%) versus deviant alone conditions (standards were omitted). Methods: Nine healthy subjects performed the 3 tasks (reading, counting and button pressing) under two conditions. Standard and target electrical stimuli were presented in a random order to the index or middle fingers of the left hand at a constant 800 ms interstimulus interval in the oddball conditions. In the deviant alone conditions, only target stimuli were presented with the same timing as in the oddball conditions. Results: The N140 amplitude increased for the deviant alone stimuli compared with the oddball standard and target stimuli regardless of whether the task was passive or active, indicating passive shifts of attention related to temporal infrequency. The P100 amplitude also increased for the deviant alone stimuli compared with the oddball standard and target stimuli in both passive and active tasks, but the enhancement seemed to be even smaller than that of the N140 amplitude. Conclusions: The somatosensory N140 passively increased even if subjects tried to attend actively to the stimulus source when the deviant alone condition was used. This change in N140 amplitude may be related to a strong orienting effect against a 'silent' background. Significance: The present study provided evidence that the N140 is an indicator of passive attention against a silent background when the deviant alone condition or long interstimulus interval was used. (C) 2004 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., 2004, 115, 871, 879, Scientific journal, 10.1016/j.clinph.2003.11.037

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• Refereed, Clin Neurophysiol, ELSEVIER SCI IRELAND LTD, Resource allocation and somatosensory P300 amplitude during dual task: effects of tracking speed and predictability of tracking direction., Kida T, Nishihira Y, Hatta A, Wasaka T, Tazoe T, Sakajiri Y, Nakata H, Kaneda T, Kuroiwa K, Akiyama S, Sakamoto M, Kamijo K, Higashiura T, Objective: The amount of attentional resources allocated to a task is determined by the intrinsic demands, also denoted as task load or difficulty of the task. Effects of resource allocation on the somatosensory N140 and P300 were investigated in an inter-modal situation using a dual-task methodology. Methods: Under a dual-task condition, subjects concurrently performed a visuomotor tracking task and a somatosensory oddball task, while they performed just the oddball task under an oddball-only condition. In the tracking task, the subjects tracked the target line, which was presented on an oscilloscope and automatically moved, with the line which represented their own force generated by grip movement with the left hand. Tracking speed (experiment 1) and tracking predictability (experiment 2) were manipulated to vary task difficulty. N140, P300, and reaction time (RT) in the oddball task and tracking accuracy in the tracking task were measured. Results: The P300 and N140 amplitudes were reduced in the dual-task condition compared to those in the oddball-only condition. The fastest tracking speed produced lower tracking accuracy and later RT. However, the tracking speed did not affect the P300 or N140 amplitudes. In contrast, the P300 amplitude was smaller when the change in tracking direction was unpredictable than when it was predictable, without any differences in tracking accuracy or RT, N140. Conclusions: The differences in behaviors among N140, P300, and RT following manipulation of task difficulty support the multiple-resource hypothesis, which defines functionally separate pools of resources. Significance: The present study may show that the P300 amplitude reflects modality-unspecific resource at more central level, and that the N140 amplitude involves perceptual resource. (C) 2004 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., 2004, 115, 2616, 2628, Scientific journal, 10.1016/j.clinph.2004.06.013

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• Refereed, Clin Neurophysiol, ELSEVIER SCI IRELAND LTD, Cognitive processes in two-point discrimination: an ERP study., Tamura Y, Hoshiyama M, Inui K, Nakata H, Wasaka T, Ojima S, Inoue K, Kakigi R, Objective: To elucidate the temporal features of the cognitive process in two-point discrimination (TPD). Methods: We measured somatosensory event-related potentials (ERPs) in 9 subjects during the TPD task, in which we provided a pair of electrical pulses simultaneously, altering the distance between the electrodes. We analyzed the TPD-related ERPs and investigated the relationship between the potentials and the subjects' judgments. Results: During the TPD task, a negative potential approximately 140 ms after the stimulation (N140) was enhanced as compared to a stimulus counting task. Two late positive components, LPC-1 and LPC-2, whose peak latencies were 300 and 500 ms, respectively, were identified only in the TPD task. The LPC-1 was recorded dominantly in the fronto-central area, while the LPC-2 was detected dominantly in the centro-parietal area. The amplitude of the LPC-2 was significantly modulated by the degree of consistency in the subjects' judgment. On the other hand, these ERP components did not show significant difference between the alternate judgments, i.e. 'one-point' or 'two-point' judgment. Conclusions: Our results suggest that the N140 is related to the attention toward the stimulation. The LPC-1 and LPC-2 are likely to correspond to the processes represented by P3a and P3b, based on their temporal and spatial behavior. (C) 2004 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved,, 2004, 115, 1875, 1884, Scientific journal, 10.1016/j.clinph.2004.03.018

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• Refereed, Neurology, LIPPINCOTT WILLIAMS & WILKINS, Facilitation of A delta-fiber-mediated acute pain by repetitive transcranial magnetic stimulation, Tamura Y, Hoshiyama M, Inui K, Nakata H, Qiu Y, Ugawa Y, Inoue K, Kakigi R, Background: Repetitive transcranial magnetic stimulation (rTMS) of the motor cortex modulates acute and chronic pain perception. The authors previously showed that rTMS over the primary motor cortex (M1) inhibited capsaicin-induced acute pain ascending through C-fibers. Objective: To investigate the effects of 1-Hz rTMS over M1 on acute experimentally induced pain mediated by Adelta-fibers (i.e., another type of acute pain). Methods: The authors examined whether rTMS over M1 affected laser evoked potentials (LEPs) in 13 normal subjects using thulium: yttrium-aluminum-garnet laser stimulation. Subjective pain-rating scores and LEPs obtained under three different conditions rTMS, realistic sham stimulation, and a control condition with no stimulation - were compared. Results: The authors found that 1-Hz rTMS over M1 significantly aggravated the subjective pain and enhanced the N2-P2 amplitudes compared with the sham or control sessions. Because the pain-rating scores and the N2-P2 amplitudes correlated positively, the N2-P2 amplitudes in the present study can be regarded as the cortical correlate of subjective pain. Conclusions: Together with the authors' previous study on C-fiber pain, this facilitatory effect of repetitive transcranial magnetic stimulation on Adelta-fiber-mediated further strengthens the notion of a relationship between repetitive transcranial magnetic stimulation over M1 and pain perception., 2004, 62, 2176, 2181, Scientific journal
• Refereed, Clin Neurophysiol, ELSEVIER SCI IRELAND LTD, Effects of a go/nogo task on event-related potentials following somatosensory stimulation., Nakata H, Inui K, Nishihira Y, Hatta A, Sakamoto M, Kida T, Wasaka T, Kakigi R, Objective: We investigated the effects of a go/nogo task on event-related potentials (ERPs) evoked by somatosensory stimuli. Methods: ERPs following electrical stimulation of the second (go stimulus) or fifth (nogo stimulus) left-handed digit were recorded from 9 subjects. The recordings were conducted in 3 conditions: Control, Count and Movement. The subjects were instructed to count the go stimuli silently in Count, and respond to the go stimuli by grasping right hands in Movement. Go and nogo stimuli were presented at an even probability. Results: N140 was recorded in all conditions and P300 in Count and Movement. The mean amplitudes of the nogo stimuli in the interval 140-200 msec and nogo-N140 amplitude were significantly more negative than those of the go stimuli in Count or Movement. Nogo-P300 was larger in amplitude than go-P300 in Movement but not Count. The effect of P300 was applied to Fz and Cz, but not at Pz. Conclusions: In the present study, effects of a somatosensory go/nogo task on ERPs were investigated, and our findings were very similar to those of previous studies using visual and auditory go/nogo tasks. Therefore, we suggest that cortical activities relating to go/nogo tasks are not dependent on sensory modalities. Significance: The present study showed for the first time the go/nogo effects on somatosensory-evoked ERPs. These effects were similar to those in visual and auditory ERP studies. (C) 2003 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., 2004, 115, 361, 368, Scientific journal, 10.1016/j.clinph.2003.09.013

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• Refereed, Pain, ELSEVIER SCIENCE BV, Movements modulate cortical activities evoked by noxious stimulation., Nakata H, Inui K, Wasaka T, Tamura Y, Tran TD, Qiu Y, Wang X, Nguyen TB, Kakigi R, To evaluate the effects of movement on cortical activities evoked by noxious stimulation, we recorded magnetoencephalography following noxious YAG laser stimulation applied to the dorsum of the left hand in normal volunteers. Results of the present study can be summarized as follows: (1) active movement of the hand ipsilateral to the side of noxious stimulation resulted in significant attenuation of both primary and secondary somatosensory cortices (SI and SII) in the hemisphere contralateral to the stimulated hand (cSI and cSII). Activity in the hemisphere ipsilateral to the side of stimulation (iSII) was not affected. (2) Active movement of the hand contralateral to the side of noxious stimulation resulted in significant attenuation of cSII. Activity in cSI and iSII was not affected. (3) Passive movement of the hand ipsilateral to the side of noxious stimulation resulted in significant attenuation of cSI. Activity in cSII and iSII was not affected. (4) Visual analogue scale (VAS) changes showed a similar pattern to the amplitude changes of cSII. These results suggest that activities in three regions are modulated by movements differently. Inhibition in cSI was considered to be mainly due to an interaction in SI by the signals ascending from the stimulated and movement hand. Inhibition in cSII was considered to be mainly due to particular brain activities relating to motor execution and/or movement execution associated with a specific attention effect. In addition, since VAS changes showed a similar relationship with the amplitude changes of cSII, cSII may play a role in pain perception. (C) 2003 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved., 2004, 107, 91, 98, Scientific journal, 10.1016/j.pain.2003.10.001

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• Not Refereed, 神経進歩, 痛覚認知のイメージング, Nakata Hiroki, 2004, 48, 261-273
• Refereed, Adv Exerc Sports Physiol, Japan Society of Exercise and Sports Physiology, Stimulus context affects P300 and reaction time during a somtosensory discrimination task., Kida T, Nishihira Y, Hatta A, Wasaka T, Nakata H, Sakamoto M, Context-dependent modulation of the somatosensory P300 and reaction time during an oddball paradigm were investigated. Subjects were instructed to respond by pressing a button with the thumb of the right hand as fast as possible whenever an infrequent target stimulus in a sequence of frequent standard stimuli was presented. According to the number of preceding standard stimuli, the raw EEG data were divided into five categories, and then averaged separately. As a result, five kinds of target-evoked ERP wave-forms were obtained at each electrode. Reaction time (RT) was shortened and P300 amplitude was increased as the number of standard stimuli preceding the target stimulus increased. These sequential effects on the P300 and RT are discussed in terms of 'expectancy'. The present results indicate that stimulus context affects the P300 and RT in a somatosensory oddball task., 2003, 9, 3, 105, 110

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• Refereed, Eur J Appl Physiol, SPRINGER-VERLAG, Changes in the somatosensory N250 and P300 by the variation of reaction time., Kida T, Nishihira Y, Hatta A, Wasaka T, Nakata H, Sakamoto M, Nakajima T, We investigated the relationship between somatosensory event-related potentials (ERP) and the variation of reaction time (RT). For this purpose, we recorded the ERPs (N250 and P300) in fast- and slow-reaction trials during a somatosensory discrimination task. Strong, standard, and weak target electrical stimuli were randomly delivered to the left median nerve at the wrist with a random interstimulus interval (900-1,100 ms). All the subjects were instructed to respond by pressing a button with their right thumb as fast as possible whenever a target stimulus was presented. We divided all the trials into fast- and slow-RT trials and averaged the data. N250 latency tended to be delayed when the RT was slow, but not significantly. P300 latency was delayed significantly when the RT was slow, but to a much lesser extent than the RT delay, so we concluded that the change of RT was not fully determined by the processes reflected by the somatosensory N250 or P300. Furthermore, the larger and earlier P300 in the fast-RT trials implied that when larger amounts of attentional resources were allocated to a given task, the speed of stimulus evaluation somewhat increased and RT was shortened to a great extent. N250 amplitude did not significantly vary in the two RT clusters. In conclusion, the somatosensory N250 reflects active target detection, which is relatively independent of the modulation of the response speed, whereas the somatosensory P300 could change without manipulation of either the stimulus or the response processing demand., 2003, 89, 326, 330, Scientific journal, 10.1007/s00421-003-0801-y

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• Refereed, NeuroImage, ACADEMIC PRESS INC ELSEVIER SCIENCE, Gating of somatosensory evoked magnetic fields during the preparatory period of self-initiated finger movement., Wasaka T, Hoshiyama M, Nakata H, Nishihira Y, Kakigi R, The temporal change in somatosensory evoked magnetic fields (SEFs) in the preparatory period of self-initiated voluntary movement was investigated. The SEF following stimulation of the right median nerve was recorded, using a 204-channel whole-head MEG system, in nine healthy subjects during a self-initiated extension of the right index finger every 5 to 7 s. The preparatory period before finger movement was divided into six subperiods, and the MEG signals following the stimulation in each subperiod were averaged separately. SEFs were also recorded in the resting state. The ECD strengths for N20m and P60m were not significantly changed in any subperiod before movement compared with those in the resting state. The ECD strength for P30m was significantly smaller 500 ms or less before movement than during the resting state and 1500 ms or less before movement compared to that during the period from 3000 to 4000 ms before movement. Thus, we confirmed that the SEF components were attenuated even during a period of self-initiated voluntary movement. The modulation started at least 1500 ms before movement and was greater for the P30m than the N20m component. These findings suggested that motor-associated cortices attenuated SEF components by a centrifugal gating process. (C) 2003 Elsevier Inc. All rights reserved., 2003, 20, 1830, 1838, Scientific journal, 10.1016/S1053-8119(03)00442-7

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• Refereed, Eur J Neurosci, BLACKWELL PUBLISHING LTD, Pain processing within the primary somatosensory cortex in humans., Inui K, Wang X, Qiu Y, Nguyen BT, Ojima S, Tamura Y, Nakata H, Wasaka T, Tran TD, Kakigi R, To investigate the processing of noxious stimuli within the primary somatosensory cortex (SI), we recorded magnetoencephalography following noxious epidermal electrical stimulation (ES) and innocuous transcutaneous electrical stimulation (TS) applied to the dorsum of the left hand. TS activated two sources sequentially within SI: one in the posterior bank of the central sulcus and another in the crown of the postcentral gyrus, corresponding to Brodmann's areas 3b and 1, respectively. Activities from area 3b consisted of 20- and 30-ms responses. Activities from area 1 consisted of three components peaking at 26, 36 and 49 ms. ES activated one source within SI whose location and orientation were similar to those of the TS-activated area 1 source. Activities from this source consisted of three components peaking at 88, 98 and 109 ms, later by 60 ms than the corresponding TS responses. ES and TS subsequently activated a similar region in the upper bank of the sylvian fissure, corresponding to the secondary somatosensory cortex (SII). The onset latency of the SII activity following ES (109 ms) was later by 29 ms than that of the first SI response (80 ms). Likewise, the onset latency of SII activity following TS (52 ms) was later by 35 ms than that of area 1 of SI (17 ms). Therefore, our results showed that the processing of noxious and innocuous stimuli is similar with respect to the source locations and activation timings within SI and SII except that there were no detectable activations within area 3b following noxious stimulation., 2003, 18, 2859, 2866, Scientific journal, 10.1046/j.1460-9568.2003.02995.x

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• Refereed, Brain Topogr, Mechanisms of differences in gating effects on short- and long-latency somatosensory evoked potentials relating to movement., Nakata H, Inui K, Wasaka T, Nishihira Y, Kakigi R, We investigated the mechanisms underlying the differences in gating effects on short- and long-latency somatosensory evoked potentials (SEPs) relating to movement. SEPs were recorded in normal subjects for 6 different tasks in Experiment 1: Control, Movement, Distraction, Attention, Movement during Distraction and Movement during Attention, and for 4 different tasks in Experiment 2: Control, Passive Movement, Contralateral Movement and Movement Imagery. The amplitudes of short-latency SEPs were significantly reduced by active and passive movement of the stimulated hand, but long-latency SEPs (N140-P200) were significantly enhanced by active movement of the stimulated hand. Attention, Distraction, Contralateral Movement and Movement Imagery did not affect the amplitudes of SEPs. The degree of enhancement of long-latency SEPs by active Movement was greater than that by active movement with Attention or Distraction. Gating effects on long-latency SEPs were different from those on short-latency SEPs. Since this effect was not related to Attention/Distraction, Passive Movement, Movement Imagery or Movement of another site, it is probably due to specific centrifugal effects, which are different from more direct gating effects on short-latency components. This study showed the difference in gating effects on somatosensory perception depending on time periods following stimulation, which may indicate an interaction between motor and somatosensory cortex., 2003, 15, 211, 222, Scientific journal, 10.1023/A:1023908707851

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• Refereed, J Mot Learn Dev, Kinematic characteristics of the standing long jump in young children aged 4-5 years., Ogawa M, Ohtaka C, Fujiwara M, Nakata H, 2021, 9, 80, 94, Scientific journal
• Refereed, 陸上競技研究紀要, 短距離走者を対象とした心理テストの時間的変動性の検討, 橋本泰裕、中田大貴, 2020, 16, 54, 61, Scientific journal
• Refereed, PLoS One, Effects of passive heat stress and recovery on human cognitive function: An ERP study., Nakata H, Kakigi R, Shibasaki M, 2021, 16, e0254769, Scientific journal
• Not Refereed, 建築と社会, スポーツの構造学 ～フリースローを例に～, 中田大貴, 2021, 102, 22, 23
• Refereed, PLoS One, Public Library of Science (PLoS), Modality differences in ERP components between somatosensory and auditory Go/No-go paradigms in prepubescent children., Nakata H, Takezawa M, Kamijo K, Shibasaki M, We investigated modality differences in the N2 and P3 components of event-related potentials (ERPs) between somatosensory and auditory Go/No-go paradigms in eighteen healthy prepubescent children (mean age: 125.9±4.2 months). We also evaluated the relationship between behavioral responses (reaction time, reaction time variability, and omission and commission error rates) and amplitudes and latencies of N2 and P3 during somatosensory and auditory Go/No-go paradigms. The peak latency of No-go-N2 was significantly shorter than that of Go-N2 during somatosensory paradigms, but not during auditory paradigms. The peak amplitude of P3 was significantly larger during somatosensory than auditory paradigms, and the peak latency of P3 was significantly shorter during somatosensory than auditory paradigms. Correlations between behavioral responses and the P3 component were not found during somatosensory paradigms. On the other hand, in auditory paradigms, correlations were detected between the reaction time and peak amplitude of No-go-P3, and between the reaction time variability and peak latency of No-go-P3. A correlation was noted between commission error and the peak latency of No-go-N2 during somatosensory paradigms. Compared with previous adult studies using both somatosensory and auditory Go/No-go paradigms, the relationships between behavioral responses and ERP components would be weak in prepubescent children. Our data provide findings to advance understanding of the neural development of motor execution and inhibition processing, that is dependent on or independent of the stimulus modality., 2021, 16, 11, e0259653, e0259653, Scientific journal, 10.1371/journal.pone.0259653

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• Not Refereed, 子どもと発育発達, スポーツにおける早生まれの成長格差, 中田大貴, 2021, 19, 10, 14, Scientific journal
• Refereed, 体力科学, 骨盤臓器脱の予防・改善にむけた骨盤底筋エクササイズ ～女性のライフステージと生活行動の視点から～, 辻野和美、大高千明、中田大貴、三輪好生, 2022, 71, 271, 278
• Not Refereed, デサントスポーツ科学, 暑熱環境下における皮質脊髄路の興奮性の検討, 中田大貴; 芝﨑学, 2022, 42, 170, 182
• Refereed, IBRO Neurosci Rep, Differences in the neural networks of thermal sensation with and without evaluation process., Nagashima K, Nakata H, Harada T, Kato I, Sadato N, 2022, 13, 274, 283
• Refereed, 体育学研究, 幼児における疾走動作の観察的評価と疾走能力との関係, 鈴木康介、後藤悠太、欠畑岳、中田大貴、彼末一之, 2022, 67, 947, 959
• Refereed, J Mot Learn Dev, The developmental progression and sex differences in agility during continuous two-footed jumping among children aged 4 to 16 years., Muro A, Takatoku N, Ohtaka C, Fujiwara M, Nakata H, 2023, 11, 71, 85, Scientific journal
• Refereed, Front Sports Act Living, Frontiers Media SA, Performance-environment mutual flow model using big data on baseball pitchers., Hashimoto Y, Nakata H, Introduction The study investigated the baseball pitching performance in terms of release speed, spin rate, and 3D coordinate data of the release point depending on the ball and strike counts. Methods We used open data provided on the official website of Major League Baseball (MLB), which included data related to 580 pitchers who pitched in the MLB between 2015 and 2019. Results The results show that a higher ball count corresponds to a slower release speed and decreased spin rate, and a higher strike count corresponds to a faster release speed and increased spin rate. For a higher ball count, the pitcher's release point tended to be lower and more forward, while for a higher strike count, the pitcher's release point tended to be to the left from the right pitcher's point of view. This result was more pronounced in 4-seam pitches, which consisted the largest number of pitchers. The same tendency was confirmed in other pitches such as sinker, slider, cut ball, and curve. Discussion Our findings suggest that the ball count is associated with the pitcher's release speed, spin rate, and 3D coordinate data. From a different perspective, as the pitcher's pitching performance is associated with the ball and strike count, the ball and strike count is associated with pitching performance. With regard to the aforementioned factor, we propose a “performance-environment flow model,” indicating that a player's performance changes according to the game situation, and the game situation consequently changes the player's next performance., 2022, 4, 967088, Scientific journal, 10.3389/fspor.2022.967088

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• Refereed, Neurosci Res, Effects of hypocapnia and hypercapnia on human somatosensory processing., Nakata H, Kakigi R, Kubo H, Shibasaki M, The present study investigated the effects of hypocapnia and hypercapnia on human somatosensory processing by utilizing somatosensory evoked magnetic fields (SEFs) with magnetoencephalography (MEG). Thirteen volunteers participated in two experiments separately to measure respiratory and cardiovascular data and SEFs. Both experiments consisted of a combination of normal and rapid respiratory rhythms and two inspiratory gas conditions (air and a hypercapnic gas); normal breathing with air (NB), rapid breathing with air (RB), normal breathing with the hypercapnic gas (NB+Gas), and rapid breathing with gas (RB+Gas). Partial pressures of end-tidal CO2 (PETCO2) increased during inhaling the hypercapnic gas and decreased during RB, but the RB+Gas condition continued to cause elevated PETCO2 compared with the baseline. Subsequently, middle cerebral artery blood (MCA) velocity using transcranial Doppler changed as well, while mean MCA velocity increased under the RB+Gas condition. The peak amplitude of the M60 component in SEFs was also significantly larger under with-gas than without-gas conditions, irrespective of the respiratory frequency. These results suggest that there is a close relationship between cerebral blood flow and neural activity of the M60 component in SEFs. This study provides evidence to further understanding on one of the neural mechanisms of hypercapnia., 2023, 190, 29, 35, Scientific journal, True, 10.1016/j.neures.2022.11.007

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• Refereed, スポーツ科学研究, スキーの小回り：なぜできない？, 彼末一之、中井宏、行方剛、西村斉、内田雄介、大室康平、加藤考基、中川剣人、大橋拓未、後藤悠太、小澤悠、水口暢章、中田大貴、依田珠江、坂本将基、桜井良太、小林海、永見智行、村岡哲郎、中島剛、樋口貴俊、柳谷登志雄、岡田利修, 2022, 19, 127, 138
• Refereed, J Phys Fitness Sports Med, The effects of subjective effort on overground and treadmill running: A comparative analysis., Hasebe F, Miura M, Ono K, Goto Y, Nakata H, Ohtaka C, Fujiwara M, 2023, 12, 45, 57
• Refereed, J Phys Fitness Sports Med, Motor imagery and action observation of whole-body movements for experienced motor repertoire: An fNIRS study., Yokota H, Kamijo K, Mizuguchi N, Kubo H, Nakata H, 2023, 12, 108, 117, Scientific journal
• Refereed, Front Sports Act Living,, Frontiers Media SA, The relationship between pitching parameters and release points of different pitch types in major league baseball players., Hashimoto Y, Nagami T, Yoshitake S, Nakata H, Objectives The purpose of this study was to deepen our understanding of pitches and to obtain basic knowledge about pitches by comparing 4-seam and other pitches in Major League Baseball (MLB). Methods We analyzed big data for 1,820 professional baseball pitchers of MLB on release speed, spin rate, release point 3D coordinates (X, Y, and Z axes), amount of change for 4-seam, and seven changing ball types (sinker, slider, changeup, cutter, curve, split finger, and knuckle curve), using PITCHf/x and TrackMan. We also evaluated three relationships: (1) between the release points and the ball types of pitch; (2) between the amount of change in the ball and the release speed; and (3) between the release speed and the spin rate. Results The release speed was significantly slower in seven changing ball types than in the 4-seam (p &lt; 0.01, respectively). The spin rate and the amount of change (ΔX and ΔZ) were significantly different between 4-seam and seven changing ball types (p &lt; 0.01, respectively). Release point 3D coordinates (X, Y, and Z axes) were significantly different between 4-seam and slider, cutter, and curve (p &lt; 0.01, respectively). Based on these findings, the eight pitch types were mainly divided into three groups: 4-seam, curve, and off-speed pitch types. Conclusion Seven changing ball types included specific characteristics for each parameter. The correspondence among the release speed, ΔX, and ΔZ at the 3D coordinates is an arch with 4-seam as the apex. Our results suggest an effective strategy for changing the release point and displacement of a ball's trajectory to improve the performance of baseball pitchers., 2023, 5, 1113069, Scientific journal, 10.3389/fspor.2023.1113069

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• Not Refereed, 体育の科学, 私のパーソナルストーリー：運動と痛み, 中田大貴, 2023, 73, 191, 195
• Refereed, Sci Rep, Synesthesia has specific cognitive processing during Go/No-go paradigms., Aoki Y, Shibasaki M, Nakata H, 2023, 13, 6172
• Refereed, Brain Sci, Fast and stable responses during decision-making require strong inhibitory processes in soccer players., Matsutake T, Nakata H, Matsuo G, Natsuhara T, Zippo K, Watanabe K, Sugo T, 2024, in press

Books etc

• 痛みのバイオマーカーとしての機能的脳画像診断法, 真興交易（株）医書出版部, プラセボ・瞑想による鎮痛効果（p171-179）, 2020
• 未完のオリンピック, かもがわ出版, 脳が科学するオリンピック（p167-186）, 2020
• 生理心理学と精神生理学 第II巻（応用）, 北大路書房, 分担, 2017, 277-285, Not Refereed
• ペインクリニック, 真興交易（株）医書出版部, 2017, 38, 938-946, Not Refereed
• ペインクリニック, 真興交易（株）医書出版部, Nakata Hiroki, 筆頭著者, 2015, 36, 592-600, Not Refereed
• Sports Performance, Springer, Sports Performance and the Brain (p3-17), 2015, 3-12, Not Refereed

Presentations

• Poster presentation, 16 Mar. 2024, 17 Mar. 2024
• Poster presentation, 02 Dec. 2023, 03 Dec. 2023
• Oral presentation, 30 Sep. 2023, 01 Oct. 2023
• Poster presentation, 30 Aug. 2023, 01 Sep. 2023
• Invited oral presentation, 23 Aug. 2023, 24 Aug. 2023
• Poster presentation, 21 Aug. 2023
• Poster presentation, 31 May 2022, 04 Jun. 2022
• Poster presentation, 31 May 2022, 04 Jun. 2022
• Poster presentation, 31 May 2022, 04 Jun. 2022
• Poster presentation, 31 May 2022, 04 Jun. 2022
• Poster presentation, 31 May 2022, 04 Jun. 2022
• Oral presentation, 07 Jul. 2022
• Oral presentation
• Keynote oral presentation
• Oral presentation
• Oral presentation
• Oral presentation
• Oral presentation
• Oral presentation
• Oral presentation
• Invited oral presentation
• Invited oral presentation
• Oral presentation
• Invited oral presentation
• Invited oral presentation, 21 Nov. 2020
• Invited oral presentation, 20 Feb. 2020

Research Projects

• 01 Dec. 2023, 31 Jul. 2024, Principal investigator
• 10 Oct. 2023, 31 Mar. 2025, Principal investigator
• Grant-in-Aid for Scientific Research (A), 01 Apr. 2019, 31 Mar. 2023, 19H01128, Physiology and Psychology of Humidity and Wetness, 永島 計; 上條 義一郎; 中田 大貴; 眞野 博彰; 丸井 朱里, Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Waseda University, 38090000, 29300000, 8790000, 1.総括 今年度は新型コロナ感染症の伝搬のため多くの制限が生じた。特に、移動制限のため実験計画に変更の必要性が生じた。当初の計画を一部変更して以下の実験を遂行した。 2-1.蒸れ感覚にかかわる吸気湿度の関与の探索 人は環境の湿度上昇を察知し、蒸れていると表現する。しかし、この機序は明確ではない。吸気湿度および温度をコントロールした大気を吸入し、上気道内の温度と温湿度感覚の変化を測定した。蒸れ感と吸気の露点温度との関係には有意な正の相関が見られ、気道は何らかの形で絶対的湿度を感知していることが示唆された。気道の温度感覚が関与していると予想され、現在、解析を継続している。 2-2.濡れ感にあたえる温度の影響の解析 濡れ感は機械的（触覚）と温度感覚の２つの独立したモダリティーにより形成されると予想されている。実験では濡れ感が物体（濾紙を使用）の含水量と濡れ感の相関を調べ、さらに濡れ感に温度がどのように修飾するのかを目的とした。30℃にコントロールした濾紙を触知させると全体として含水量との相関が見られた。しかし、個体差がおおきく、その機序は不明であった。一方、温度は蒸れ感に明確な影響をあたえ、皮膚表面温度をこえる32℃以上の条件で実験をおこなうと濡れ感は一定のままで影響を認めなかった。一方、低温刺激では濡れ感と温度の間に負の相関が認められた。 2-3.マスク着用による運動時の生理学的および心理学的応答への影響の解析 マスク着用により顔面装着部の局所湿度が上昇することを明らかにしていた。このため、研究の社会実装を目指して、マスク着用による高温高湿度環境下でのマスクの影響を調べた。マスク着用による低強度、中強度運動は、循環および体温調節への影響は認められなかった。しかし、蒸れ感を長時間の着用で惹起した。マスク着用による装着部の湿度環境は熱中症リスクにはならないことを明らかにし、論文化した。, kaken

  対象リソースIRI
• Grant-in-Aid for Scientific Research (C), 01 Apr. 2019, 31 Mar. 2022, 19K11576, Exploring neuroscientific biomarkers of motor learning in children, Nakata Hiroki, Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Nara Women's University, 4160000, 3200000, 960000, It is an important issue in the field of physical education and sports science to elucidate the mechanisms of motor learning in children. The purpose of this study was to clarify the fundamental question, "Why are some children unable to perform movements well? In this study, I focused on gymnastics of elementary school children, and considered brain activity as a "neuroscientific biomarker of motor learning ability". I investigated the relationship between brain activity and motor performance in children., kaken

  対象リソースIRI
• 基盤研究(A), 01 Apr. 2018, 31 Mar. 2022, 18H04087, 運動イメージと協調運動の脳機構に基づくスキー技術の学習支援システム構築, 彼末 一之; 内田 雄介; 桜井 良太; 小林 海; 永見 智行; 加藤 孝基; 村岡 哲郎; 依田 珠江; 中田 大貴; 大室 康平; 中島 剛; 樋口 貴俊; 坂本 将基; 水口 暢章; 中川 剣人, 日本学術振興会, 科学研究費助成事業, 早稲田大学, 44460000, 34200000, 10260000, 本年度は中級者にとって技術の1つの壁である小回り技術を複数被験者の複数ターンを計測対象として分析した。筋活動や足圧などの複数の指標によって計測するシステムを開発、加えて、そのシステムによって計測されたデータから、スキー中級者及び上級者の小回り動作の技術的特徴を客観的に評価する方法を検討する。実験は夏期と冬期の2回実施した。夏期は被験者は成人男性 4 人であり、基礎スキーや競技スキーの国内大会に出場しているスキー上級者であった。筋活動の測定箇所は左右の前脛骨筋、腓腹筋内側頭、大腿直筋、大腿二頭筋、長内転筋の合計 10か所であった。足圧は母指球直下、小指球直下、踵直下の 3 か所であった。被験者には特殊なマットの敷かれたサマーゲレンデ内で、ターンの横幅3m 程度を目安に小回り動作を行ってもらった。被験者が測定区間内で行ったすべてのターンを方向ごとに分類し、加算平均した。、腓腹筋内側頭、大腿二頭筋など、脚部後部の筋活動に関しては、被験者ごとに異なる特徴を得た。その原因としては、被験者の熟練度が高いことが考えられる。母指球の足圧変化について、踵の足圧と同時期に圧力上昇する被験者とそうでない被験者がおり、その原因として競技的特性が挙げられた。冬期は被験者は成人男性 4名であり、全員が日本スキー連盟（SAJ）の定めるバッチテストで 1 級を取得していた。被験者は冬のゲレンデでショートポールの小回りを行った。踵部への圧力は、外側内側ともにすべての被験者に共通して周期性を持った足圧の変化が見られた。その周期とは、切り替え局面で圧が弱まり、各ターンの頂点であるターンマックス局面で圧が強くなるというものであった。一部の被験者では、踵部にかかる圧力が強くなる局面で、同時に前脛骨筋の活動が強まった。, kaken

  対象リソースIRI
• Grant-in-Aid for Scientific Research (B), 01 Apr. 2018, 31 Mar. 2022, 18H03166, Effects of central and peripheral fatigue on muscle output regulation and circulatory regulation during exercise in a hot environment, Shibasaki Manabu, Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Nara Women's University, 17160000, 13200000, 3960000, We investigated the effects of central and peripheral fatigues on motor control and cardiovascular responses during exercise in a hot environment using electroencephalographic event-related potentials, near-infrared spectroscopy, and middle cerebral artery blood velocity. In addition, to investigate the motor skill with muscle fatigue, we examined the interlocking of upper and lower limbs movements. The results of hyperthermia-induced central fatigue showed that the mode of exercise is capable of modulating the central motor command. Also, the peripheral fatigue affects the output of the central motor command, which is brain activity. Finally, "how to relax" due to muscle fatigue was numerically presented., kaken

  対象リソースIRI
• Grant-in-Aid for Young Scientists (A), 01 Apr. 2015, 31 Mar. 2018, 15H05361, Effects of passive heat stress on human cognitive processing., Hiroki Nakata; Shibasaki Manabu; Kakigi Ryusuke, Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Nara Women's University, 7150000, 5500000, 1650000, Climate change has had a widespread impact on humans and natural systems. Heat exhaustion is a heat-related illness that can occur after exposure to hot environments. Signs include excessive thirst, weakness, headache, loss of consciousness, dizziness, muscle cramps, nausea, and vomiting. Heat exhaustion is not as serious as heat stroke, but without proper intervention, it can progress to heat stroke, which can damage the brain and other vital organs. The present study focused on the human cognitive function by using psychological, physiological, and neuroscientific methods after exposure to hot environments. We also investigated the effect of general treatment for heat exhaustion on the function., kaken

  対象リソースIRI
• Grant-in-Aid for Scientific Research (A), 01 Apr. 2014, 31 Mar. 2018, 26242065, The analysis of the role and its brain mechanism of motor imagery in motor skill learning, Kanosue Kazuyuki, Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Waseda University, 43420000, 33400000, 10020000, Personal difference in the ability of learning of new motor skill, especially that of diffifult action, is big. One of the reason of this is that motor learning involves not only gaining the motor action itself, but also having appropriate motor image of the action. In this research we analyzed brain activities during the process of motor learning under the hypothesis that motor learning is the process of interpretting motor images of objective third-person perspective into the motor images of first-person perspective. As results, it was suggested that at the initial stage of learning third-person perspective images are dominant and strongly related to the quality of motor performance, and as the learning progresses, first-person person perspective images become dominant., kaken

  対象リソースIRI
• Grant-in-Aid for Scientific Research (B), 01 Apr. 2013, 31 Mar. 2018, 25280101, Clarifying mechanisms involved in thermal pleasantness/unpleasantness and the application for evaluation of the inside environment of clothes, Nagashima Kei; Marui Shuri; Aizawa Yuka, Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Waseda University, 16900000, 13000000, 3900000, ① Development of a method to experimentally reproduce thermal discomfort, ② Development of a method to reproduce ① in the brain function imaging device (fMRI) and obtain brain function image. Hypothesis verification that temperature sensation sensation and thermal discomfort feeling are processed in different brain regions. ③ Eluciation of the mechanism of transformation of thermal discomfort seen during exercise and dehydration from the changes in deep body temperature and skin temperature. For ①, regional temperature difference of the body surface can be reproduced by constructing it by a combination of rise and fall of body surface skin temperature with water perfusion suit and local skin temperature stimulation. ② Different brain regions were involved in temperature perception (discriminative and hedonic components). ③ Possible contribution to the thermal discomfort feeling other than the temperature parameter per se was clarified., kaken

  対象リソースIRI
• Grant-in-Aid for Challenging Exploratory Research, 01 Apr. 2012, 31 Mar. 2014, 24650396, Analysis of eye movement and visual recognition ability in elite baseball players, KANOSUE Kazuyuki, Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Waseda University, 3900000, 3000000, 900000, Seeing from a baseball batter, the angular velocity of a ball thrown at 140km/h reaches as high as 1000deg/s. However, batters can hit the ball. This indicates good ability of recognition in baseball players. In this study, we analyzed eye-movement-recognition system in elite baseball balayers. Results indicates that they have high miximum speed of eye-movement, but the recognition at a given retinal slip is comparable to that of non-players. Furthermore, we analyzed what kind of information batters use, utilizing shatter googles. Interestingly, batters use visual information in the period till only 150ms after the ball release., kaken

  対象リソースIRI