研究者詳細 - 平井　真洋

論文 - 平井　真洋

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Communicative Hand‐Waving Gestures Facilitate Object Learning in Preverbal Infants

Masahiro Hirai, Yasuhiro Kanakogi

Developmental Science 頁： e12787 - e12787 2018年12月

Hypoactivation of the Right Prefrontal Cortex Underlying Motor-Related Inhibitory Deficits in Children with Autism Spectrum Disorder: A Functional Near-Infrared Spectroscopy Study

Takahiro Ikeda, Tatsuya Tokuda, Yukifumi Monden, Masahiro Hirai, Sakae G. Mizushima, Masako Nagashima, Yasushi Kyutoku, Takamichi Taniguchi, Hideo Shimoizumi, Ippeita Dan, Takanori Yamagata

Japanese Psychological Research 60 巻 ( 4 ) 頁： 251 - 264 2018年10月

Atypical neural modulation in the right prefrontal cortex during an inhibitory task with eye gaze in autism spectrum disorder as revealed by functional near-infrared spectroscopy. 査読有り国際誌

Takahiro Ikeda, Masahiro Hirai, Takeshi Sakurada, Yukifumi Monden, Tatsuya Tokuda, Masako Nagashima, Hideo Shimoizumi, Ippeita Dan, Takanori Yamagata

Neurophotonics 5 巻 ( 3 ) 頁： 035008 - 035008 2018年7月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

Autism spectrum disorder (ASD) is characterized by impairment in social communication and the presence of restricted and repetitive behaviors and interests. Executive function impairment is reportedly partially responsible for these symptoms. Executive function includes planning, flexibility, and inhibitory control. Although planning and flexibility in ASD have been consistently reported as atypical, the atypicality of inhibitory control remains controversial. As most previous studies have used nonsocial stimuli to investigate inhibitory control in ASD, the effects of socially relevant information on the inhibitory control system in individuals with ASD remain unclear. Therefore, we developed a go/no-go task with gaze stimuli and measured hemodynamic responses in the right prefrontal cortex (PFC), involved in inhibitory processing in both typically developing (TD) children and children with ASD, using functional near-infrared spectroscopy. Direct gaze induced commission errors to similar extents in both groups. Contrary to the behavioral responses, neural activation in the right PFC was modulated by gaze direction only in the TD group. These findings suggest that the gaze-processing mechanisms in the prefrontal region may be affected by atypical gaze processing in other brain regions during an inhibitory control task with socially relevant information in ASD.

DOI： 10.1117/1.NPh.5.3.035008

PubMed

Probing links between action perception and action production in Parkinson's disease using Fitts' law 査読有り

Takeshi Sakurada, Guenther Knoblich, Natalie Sebanz, Shin-ichi Muramatsu, Masahiro Hirai

Neuropsychologia 111 巻頁： 201 - 208 2018年3月

担当区分：最終著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Elsevier Ltd

Information on how the subcortical brain encodes information required to execute actions or to evaluate others’ actions remains scanty. To clarify this link, Fitts'-law tasks for perception and execution were tested in patients with Parkinson's disease (PD). For the perception task, participants were shown apparent motion displays of a person moving their arm between two identical targets and reported whether they judged that the person could realistically move at the perceived speed without missing the targets. For the motor task, participants were required to touch the two targets as quickly and accurately as possible, similarly to the person observed in the perception task. In both tasks, the PD group exhibited, or imputed to others, significantly slower performances than those of the control group. However, in both groups, the relationships of perception and execution with task difficulty were exactly those predicted by Fitts’ law. This suggests that despite dysfunction of the subcortical region, motor simulation abilities reflected mechanisms of compensation in the PD group. Moreover, we found that patients with PD had difficulty in switching their strategy for estimating others’ actions when asked to do so.

DOI： 10.1016/j.neuropsychologia.2018.02.001

Scopus

Preserved search asymmetry in the detection of fearful faces among neutral faces in individuals with Williams syndrome revealed by measurement of both manual responses and eye tracking 査読有り

Masahiro Hirai, Yukako Muramatsu, Seiji Mizuno, Naoko Kurahashi, Hirokazu Kurahashi, Miho Nakamura

JOURNAL OF NEURODEVELOPMENTAL DISORDERS 9 巻頁： 8 2017年3月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：BIOMED CENTRAL LTD

Background: Individuals with Williams syndrome (WS) exhibit an atypical social phenotype termed hypersociability. One theory accounting for hypersociability presumes an atypical function of the amygdala, which processes fear-related information. However, evidence is lacking regarding the detection mechanisms of fearful faces for individuals with WS. Here, we introduce a visual search paradigm to elucidate the mechanisms for detecting fearful faces by evaluating the search asymmetry; the reaction time when both the target and distractors were swapped was asymmetrical.
Methods: Eye movements reflect subtle atypical attentional properties, whereas, manual responses are unable to capture atypical attentional profiles toward faces in individuals with WS. Therefore, we measured both eye movements and manual responses of individuals with WS and typically developed children and adults in visual searching for a fearful face among neutral faces or a neutral face among fearful faces. Two task measures, namely reaction time and performance accuracy, were analyzed for each stimulus as well as gaze behavior and the initial fixation onset latency.
Results: Overall, reaction times in the WS group and the mentally age-matched control group were significantly longer than those in the chronologically age-matched group. We observed a search asymmetry effect in all groups: when a neutral target facial expression was presented among fearful faces, the reaction times were significantly prolonged in comparison with when a fearful target facial expression was displayed among neutral distractor faces. Furthermore, the first fixation onset latency of eye movement toward a target facial expression showed a similar tendency for manual responses.
Conclusions: Although overall responses in detecting fearful faces for individuals with WS are slower than those for control groups, search asymmetry was observed. Therefore, cognitive mechanisms underlying the detection of fearful faces seem to be typical in individuals with WS. This finding is discussed with reference to the amygdala account explaining hypersociability in individuals with WS.

DOI： 10.1186/s11689-017-9190-0

Web of Science

Improved motor performance in patients with acute stroke using the optimal individual attentional strategy 査読有り

Takeshi Sakurada, Takeshi Nakajima, Mitsuya Morita, Masahiro Hirai, Eiju Watanabe

SCIENTIFIC REPORTS 7 巻頁： :40592 2017年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：NATURE PUBLISHING GROUP

It is believed that motor performance improves when individuals direct attention to movement outcome (external focus, EF) rather than to body movement itself (internal focus, IF). However, our previous study found that an optimal individual attentional strategy depended on motor imagery ability. We explored whether the individual motor imagery ability in stroke patients also affected the optimal attentional strategy for motor control. Individual motor imagery ability was determined as either kinesthetic- or visual-dominant by a questionnaire in 28 patients and 28 healthy-controls. Participants then performed a visuomotor task that required tracing a trajectory under three attentional conditions: no instruction (NI), attention to hand movement (IF), or attention to cursor movement (EF). Movement error in the stroke group strongly depended on individual modality dominance of motor imagery. Patients with kinesthetic dominance showed higher motor accuracy under the IF condition but with concomitantly lower velocity. Alternatively, patients with visual dominance showed improvements in both speed and accuracy under the EF condition. These results suggest that the optimal attentional strategy for improving motor accuracy in stroke rehabilitation differs according to the individual dominance of motor imagery. Our findings may contribute to the development of tailor-made pre-assessment and rehabilitation programs optimized for individual cognitive abilities.

DOI： 10.1038/srep40592

Web of Science

脳卒中患者の認知運動機能連関に関する個人差とその神経基盤招待有り

櫻田武, 後藤彩, 中嶋剛, 森田光哉, 平井真洋, 山本紳一郎, 渡辺英寿, 川合謙介

機能的脳神経外科 56 巻頁： 62 - 67 2017年

Intact attentional orienting towards inverted faces revealed by both manual responses and eye-movement measurement in individuals with Williams syndrome 査読有り

M. Hirai, Y. Muramatsu, S. Mizuno, N. Kurahashi, H. Kurahashi, M. Nakamura

JOURNAL OF INTELLECTUAL DISABILITY RESEARCH 60 巻 ( 10 ) 頁： 969 - 981 2016年10月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：WILEY-BLACKWELL

Background Individuals with Williams syndrome (WS) exhibit atypical attentional characteristics when viewing faces. Although atypical configural processing of faces has been reported in WS, the relative strengths of configural and local feature information to capture visual attention in WS remains unclear. We previously demonstrated that attentional capture by target-unrelated upright faces differs depending on what response is measured. Whereas eye movements reflected subtle atypical attentional properties at the late stage of visual search, manual responses could not capture the atypical attentional profiles towards target-unrelated upright faces in individuals with WS. Here we used the same experimental paradigm to assess whether sensitivity to configural facial information is necessary for capturing attention in WS.
Methods We measured both eye movements and manual responses from 17 individuals with WS and 34 typically developing children and adults while they were actively involved in a visual search task with an inverted face distractor. Task measures (reaction time and performance accuracy) and gaze behaviour (initial direction of attention and fixation duration) were analysed for each stimulus.
Results When the target and the inverted face were displayed in the same search array, reaction times and accuracies in individuals with WS showed similar tendencies as typical controls. Analysis of task and gaze measures revealed that attentional orienting towards inverted faces was not atypical.
Conclusion Although individuals with WS exhibited atypical gaze behaviour towards upright faces in our previous study, this unusual behaviour disappears if the faces are upside down. These findings suggest that local feature information alone (e.g. eyes) does not contribute to the heightened attention to faces, but configural information appears necessary for drawing attention to faces in individuals with WS, at least in the current experimental paradigm.

DOI： 10.1111/jir.12318

Web of Science

Typical visual search performance and atypical gaze behaviors in response to faces in Williams syndrome 査読有り

Masahiro Hirai, Yukako Muramatsu, Seiji Mizuno, Naoko Kurahashi, Hirokazu Kurahashi, Miho Nakamura

JOURNAL OF NEURODEVELOPMENTAL DISORDERS 8 巻頁： 38 2016年10月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：BIOMED CENTRAL LTD

Background: Evidence indicates that individuals with Williams syndrome (WS) exhibit atypical attentional characteristics when viewing faces. However, the dynamics of visual attention captured by faces remain unclear, especially when explicit attentional forces are present. To clarify this, we introduced a visual search paradigm and assessed how the relative strength of visual attention captured by a face and explicit attentional control changes as search progresses.
Methods: Participants (WS and controls) searched for a target (butterfly) within an array of distractors, which sometimes contained an upright face. We analyzed reaction time and location of the first fixation-which reflect the attentional profile at the initial stage-and fixation durations. These features represent aspects of attention at later stages of visual search. The strength of visual attention captured by faces and explicit attentional control (toward the butterfly) was characterized by the frequency of first fixations on a face or butterfly and on the duration of face or butterfly fixations.
Results: Although reaction time was longer in all groups when faces were present, and visual attention was not dominated by faces in any group during the initial stages of the search, when faces were present, attention to faces dominated in the WS group during the later search stages. Furthermore, for the WS group, reaction time correlated with eye-movement measures at different stages of searching such that longer reaction times were associated with longer face-fixations, specifically at the initial stage of searching. Moreover, longer reaction times were associated with longer face-fixations at the later stages of searching, while shorter reaction times were associated with longer butterfly fixations.
Conclusions: The relative strength of attention captured by faces in people with WS is not observed at the initial stage of searching but becomes dominant as the search progresses. Furthermore, although behavioral responses are associated with some aspects of eye movements, they are not as sensitive as eye-movement measurements themselves at detecting atypical attentional characteristics in people with WS.

DOI： 10.1186/s11689-016-9172-7

Web of Science

The Trans-Visible Navigator: A See-Through Neuronavigation System Using Augmented Reality 査読有り

Eiju Watanabe, Makoto Satoh, Takehiko Konno, Masahiro Hirai, Takashi Yamaguchi

WORLD NEUROSURGERY 87 巻頁： 399 - 405 2016年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE INC

INTRODUCTION: The neuronavigator has become indispensable for brain surgery and works in the manner of point-to-point navigation. Because the positional information is indicated on a personal computer (PC) monitor, surgeons are required to rotate the dimension of the magnetic resonance imaging/computed tomography scans to match the surgical field. In addition, they must frequently alternate their gaze between the surgical field and the PC monitor.
OBJECTIVE: To overcome these difficulties, we developed an augmented reality-based navigation system with whole-operation-room tracking.
METHODS: A tablet PC is used for visualization. The patient's head is captured by the back-face camera of the tablet. Three-dimensional images of intracranial structures are extracted from magnetic resonance imaging/computed tomography and are superimposed on the video image of the head. When viewed from various directions around the head, intracranial structures are displayed with corresponding angles as viewed from the camera direction, thus giving the surgeon the sensation of seeing through the head. Whole-operation-room tracking is realized using a VICON tracking system with 6 cameras.
RESULTS: A phantom study showed a spatial resolution of about 1 mm. The present system was evaluated in 6 patients who underwent tumor resection surgery, and we showed that the system is useful for planning skin incisions as well as craniotomy and the localization of superficial tumors.
CONCLUSIONS: The main advantage of the present system is that it achieves volumetric navigation in contrast to conventional point-to-point navigation. It extends augmented reality images directly onto real surgical images, thus helping the surgeon to integrate these 2 dimensions intuitively.

DOI： 10.1016/j.wneu.2015.11.084

Web of Science

Optimization of a motor learning attention-directing strategy based on an individual's motor imagery ability 査読有り

Takeshi Sakurada, Masahiro Hirai, Eiju Watanabe

EXPERIMENTAL BRAIN RESEARCH 234 巻 ( 1 ) 頁： 301 - 311 2016年1月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：SPRINGER

Motor learning performance has been shown to be affected by various cognitive factors such as the focus of attention and motor imagery ability. Most previous studies on motor learning have shown that directing the attention of participants externally, such as on the outcome of an assigned body movement, can be more effective than directing their attention internally, such as on body movement itself. However, to the best of our knowledge, no findings have been reported on the effect of the focus of attention selected according to the motor imagery ability of an individual on motor learning performance. We measured individual motor imagery ability assessed by the Movement Imagery Questionnaire and classified the participants into kinesthetic-dominant (n = 12) and visual-dominant (n = 8) groups based on the questionnaire score. Subsequently, the participants performed a motor learning task such as tracing a trajectory using visuomotor rotation. When the participants were required to direct their attention internally, the after-effects of the learning task in the kinesthetic-dominant group were significantly greater than those in the visual-dominant group. Conversely, when the participants were required to direct their attention externally, the after-effects of the visual-dominant group were significantly greater than those of the kinesthetic-dominant group. Furthermore, we found a significant positive correlation between the size of after-effects and the modality-dominance of motor imagery. These results suggest that a suitable attention strategy based on the intrinsic motor imagery ability of an individual can improve performance during motor learning tasks.

DOI： 10.1007/s00221-015-4464-9

Web of Science

Differential electrophysiological responses to biological motion in children and adults with and without autism spectrum disorders 査読有り

Masahiro Hirai, Atsuko Gunji, Yuki Inoue, Yosuke Kita, Takashi Hayashi, Kengo Nishimaki, Miho Nakamura, Ryusuke Kakigi, Masumi Inagaki

RESEARCH IN AUTISM SPECTRUM DISORDERS 8 巻 ( 12 ) 頁： 1623 - 1634 2014年12月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCI LTD

Although atypical processing of biological motion (BM) in individuals with autism spectrum disorder (ASD) has been reported, the temporal profile of the neural response to BM is not well explored. In the current study, event-related potentials (ERPs) were measured in 12 individuals with ASD, aged 8-22 years, and 12 age- and gender-matched normal controls, to investigate the electrophysiological response to BM and a control visual stimulus. By introducing a novel experimental paradigm that can dissociate the electrophysiological responses to motion processing and the global shape processing of BM, we found that: (1) the timing of the response was preserved in ASD groups, whereas (2) the ERP response to BM was significantly enhanced compared with scrambled point-light motion (SM) in normal controls; the responses to both BM and SM were not significantly different in subjects with ASD. Because we did not find a significant group effect on the peak and mean amplitude induced by BM, it is presumed that this atypical response in individuals with ASD was due to over-sensitivity to the local motion signals. This experimental paradigm showed atypical local motion processing of BM in individuals with ASD. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.rasd.2014.08.014

Web of Science

Absent activation in medial prefrontal cortex and temporoparietal junction but not superior temporal sulcus during the perception of biological motion in schizophrenia: a functional MRI study 査読有り

Naoki Hashimoto, Atsuhito Toyomaki, Masahiro Hirai, Tamaki Miyamoto, Hisashi Narita, Ryo Okubo, Ichiro Kusumi

NEUROPSYCHIATRIC DISEASE AND TREATMENT 10 巻頁： 2221 - 2230 2014年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：DOVE MEDICAL PRESS LTD

Background: Patients with schizophrenia show disturbances in both visual perception and social cognition. Perception of biological motion (BM) is a higher-level visual process, and is known to be associated with social cognition. BM induces activation in the "social brain network", including the superior temporal sulcus (STS). Although deficits in the detection of BM and atypical activation in the STS have been reported in patients with schizophrenia, it remains unclear whether other nodes of the "social brain network" are also atypical in patients with schizophrenia.
Purpose: We aimed to explore whether brain regions other than STS were involved during BM perception in patients with schizophrenia, using functional magnetic resonance imaging (fMRI).
Methods and patients: Seventeen patients with schizophrenia, and 17 age-and sex-matched healthy controls, underwent fMRI scanning during a one-back visual task, containing three experimental conditions: (1) BM, (2) scrambled motion (SM), and (3) static condition. We used one-sample t-tests to examine neural responses selective to BM versus SM within each group, and two-sample t-tests to directly compare neural patterns to BM versus SM in schizophrenics versus controls.
Results: We found significant activation in the STS region when BM was contrasted with SM in both groups, with no significant difference between groups. On the contrary, significant activation in the medial prefrontal cortex (MPFC) and bilateral temporoparietal junction (TPJ) was found only in the control group. When we directly compared the two groups, the healthy controls showed significant greater activation in left MPFC and TPJ to BM versus SM than patients with schizophrenia.
Conclusion: Our findings suggest that patients with schizophrenia show normal activation to biologically and socially relevant motion stimuli in the STS, but atypical activation in other regions of the social brain network, specifically MPFC and TPJ. Moreover, these results were not due to atypical processing of motion, suggesting that patients with schizophrenia lack in the recruitment of neural circuits needed for the visual perception of social cognition.

DOI： 10.2147/NDT.S70074

Web of Science

Developmental changes in point-light walker processing during childhood: A two-year follow-up ERP study 査読有り

Masahiro Hirai, Shoko Watanabe, Yukiko Honda, Ryusuke Kakigi

DEVELOPMENTAL COGNITIVE NEUROSCIENCE 5 巻頁： 51 - 62 2013年7月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCI LTD

Event-related potentials were measured in twenty-four children aged 6-15 years, at one-year intervals for two years, to investigate developmental changes in each subject's neural response to a point-light walker (PLW) and a scrambled PLW (sPLW) stimulus. One positive peak (P1) and two negative peaks (N1 and N2) were observed in both occipitotemporal regions at approximately 130, 200, and 300-400 ms. The amplitude and latency of the P1 component measured by the occipital electrode decreased during development over the first one-year period. Negative amplitudes of both N1 and N2, induced by the PLW stimulus, were significantly larger than those induced by the sPLW stimulus. Moreover, for the P1-N1 amplitude, the values for the eight-year-old children were significantly larger than those for the twelve-year-old children. N1 and N2 latency at certain electrodes decreased with age, but no consistent changes were observed. These results suggest that enhanced electrophysiological responses to PLW can be observed in all age groups, and that the early components were changed even over the course of a single year at the age of twelve. (C) 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.dcn.2013.01.002

Web of Science

Electrophysiological study of face inversion effects in Williams syndrome 査読有り

Miho Nakamura, Shoko Watanabe, Masumi Inagaki, Masahiro Hirai, Kensaku Miki, Yukiko Honda, Ryusuke Kakigi

BRAIN & DEVELOPMENT 35 巻 ( 4 ) 頁： 323 - 330 2013年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE BV

Objective: In order to evaluate whether face perception is intact or not in Williams syndrome (WS), the face inversion effects (FIE) in the event-related potential (ERP) or magnetoencephalography (MEG) were investigated in three teenaged patients with WS. Methods: Responses to the inverted faces and upright faces were compared using MEG for one 13 year old girl with WS (subject A) and ERP for boys with WS at 16 and 14 years of age (subjects B and C, respectively). Results: Although age-matched control children showed FIE in both MEG and ERP studies, two subjects (A and B) with WS showed no FIE at all. The neurophysiological data of ERP in subject B was significantly different from those of the age-matched controls. On the other hand, a boy with WS (subject C) showed typical FIE in the same manner as the age-matched controls. Conclusions: The difference between those with or without FIE was not explained merely by the chronological age, a simple delay in mental age or in the ability to discriminate among upright faces. The absence of FIE may be related to the severity of a deficit in the dorsal pathway function that is characteristic to the syndrome. (C) 2012 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

DOI： 10.1016/j.braindev.2012.05.010

Web of Science

Developmental changes in mental rotation ability and visual perspective-taking in children and adults with Williams syndrome

Masahiro Hirai, Yukako Muramatsu, Seiji Mizuno, Naoko Kurahashi, Hirokazu Kurahashi, Miho Nakamura

Frontiers in Human Neuroscience 7 巻 2013年

Body Configuration Modulates the Usage of Local Cues to Direction in Biological-Motion Perception 査読有り

Masahiro Hirai, Dorita H. F. Chang, Daniel R. Saunders, Nikolaus F. Troje

PSYCHOLOGICAL SCIENCE 22 巻 ( 12 ) 頁： 1543 - 1549 2011年12月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：SAGE PUBLICATIONS INC

The presence of information in a visual display does not guarantee its use by the visual system. Studies of inversion effects in both face recognition and biological-motion perception have shown that the same information may be used by observers when it is presented in an upright display but not used when the display is inverted. In our study, we tested the inversion effect in scrambled biological-motion displays to investigate mechanisms that validate information contained in the local motion of a point-light walker. Using novel biological-motion stimuli that contained no configural cues to the direction in which a walker was facing, we found that manipulating the relative vertical location of the walker's feet significantly affected observers' performance on a direction-discrimination task. Our data demonstrate that, by themselves, local cues can almost unambiguously indicate the facing direction of the agent in biological-motion stimuli. Additionally, we document a noteworthy interaction between local and global information and offer a new explanation for the effect of local inversion in biological-motion perception.

DOI： 10.1177/0956797611417257

Web of Science

バイオロジカルモーションと身体図式招待有り

平井真洋

Clinical Neuroscience 2011年7月

The development of the perception of facial emotional change examined using ERPs. 査読有り

Miki K, Watanabe S, Teruya M, Takeshima Y, Urakawa T, Hirai M, Honda Y, Kakigi R

Clin Neurophysiol. 122 巻 ( 3 ) 頁： 530 - 538 2011年3月

身体•身体運動知覚に関する発達認知神経科学研究とその展望招待有り

平井真洋

赤ちゃん学会誌 10 巻頁： 6 - 25 2011年3月

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