Award type：Award from Japanese society, conference, symposium, etc.  Country：Japan

Award type：Award from Japanese society, conference, symposium, etc.  Country：Japan

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：SAGE Publications  

Previous studies show that newborn infants and adults orient their attention preferentially toward human faces. However, the developmental changes of visual attention captured by face stimuli remain unclear, especially when an explicit top-down process is involved. We capitalized on a visual search paradigm to assess how the relative strength of visual attention captured by a non-target face stimulus and explicit attentional control on a target stimulus evolve as search progresses and how this process changes during development. Ninety children aged 5–14 years searched for a target within an array of distractors, which occasionally contained an upright face. To assess the precise picture of developmental changes, we measured: (1) manual responses, such as reaction time and accuracy; and (2) eye movements such as the location of the first fixation, which reflect the attentional profile at the initial stage, and looking times, which reflect the attentional profile at the later period of searching. Both reaction time and accuracy were affected by the presence of the target-unrelated face, though the interference effect was observed consistently across ages. However, developmental changes were captured by the first fixation proportion, suggesting that initial attention was preferentially directed towards the target-unrelated face before 6.9 years of age. Furthermore, prior to 12.8 years of age, the first fixation towards face stimuli was significantly more frequent than for object stimuli. In contrast, the looking time proportion for the face stimuli was significantly higher than that for the objects across all ages. These findings suggest that developmental changes do not influence the later search periods during a trial, but that they influence the initial orienting indexed by the first fixation. Moreover, the manual responses are tightly linked to eye movement behaviors.

DOI： 10.1177/0165025419844031

Other Link： http://journals.sagepub.com/doi/full-xml/10.1177/0165025419844031

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1111/cdev.13172

Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1111/cdev.13172

Language：English   Publishing type：Research paper (scientific journal)  

Directing attention to movement outcomes (external focus; EF), not body movements (internal focus; IF), is a better cognitive strategy for motor performance. However, EF is not effective in some healthy individuals or stroke patients. We aimed to identify the neurological basis reflecting the individual optimal attentional strategy using functional near-infrared spectroscopy. Sixty-four participants (23 healthy young, 23 healthy elderly, and 18 acute stroke) performed a reaching movement task under IF and EF conditions. Of these, 13 healthy young participants, 11 healthy elderly participants, and 6 stroke patients showed better motor performance under EF conditions (EF-dominant), whereas the others showed IF-dominance. We then measured prefrontal activity during rhythmic hand movements under both attentional conditions. IF-dominant participants showed significantly higher left prefrontal activity than EF-dominant participants under IF condition. In addition, receiver operating characteristic analysis supported that the higher activity in the left frontopolar and dorsolateral prefrontal cortices could detect IF-dominance as an individual's optimal attentional strategy for preventing motor performance decline. Taken together, these results suggest that prefrontal activity during motor tasks reflects an individual's ability to process internal body information, thereby conferring IF-dominance. These findings could be applied for the development of individually optimized rehabilitation programs.

DOI： 10.1117/1.NPh.6.2.025012

PubMed

Authorship：Lead author,　Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/13803395.2018.1513452

Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1002/brb3.1183

Other Link： http://onlinelibrary.wiley.com/wol1/doi/10.1002/brb3.1183/fullpdf

Authorship：Lead author,　Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1111/desc.12787

Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1111/jpr.12204

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

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

Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Authorship：Lead author,　Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：Frontiers Media SA  

DOI： 10.3389/fnhum.2013.00856

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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

Language：Japanese   Publishing type：Research paper (other academic)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.clinph.2010.07.013

PubMed

Language：Japanese   Publishing type：Research paper (scientific journal)  

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ASSOC RESEARCH VISION OPHTHALMOLOGY INC  

Directional information can be retrieved from a point-light walker (PLW) in two different ways: either from recovering the global shape of the articulated body or from signals in the local motion of individual dots. Here, we introduce a voluntary eye movement task to assess how the direction of a centrally presented, task-irrelevant PLW affects the onset latency and accuracy of saccades to peripheral targets. We then use this paradigm to design experiments to study which aspects of biological motion-the global form mediated by the motion of the walker or the local movements of critical features-drive the observed attentional effects. Putting the two cues into conflict, we show that saccade latency and accuracy were affected by the local motion of the dots representing the walker's feet-but only if they retain their familiar, predictable location within the display.

DOI： 10.1167/11.3.4

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1371/journal.pone.0013366

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1523/JNEUROSCI.3884-10.2010

PubMed

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.neuroscience.2009.03.026

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：BIOMED CENTRAL LTD  

Background: A recent behavioral study demonstrated that the meaningful interaction of two agents enhances the detection sensitivity of biological motion (BM), however, it remains unclear when and how the 'interaction' information of two agents is represented in our neural system. To clarify this point, we used magnetoencephalography and introduced a novel experimental technique to extract a neuromagnetic response relating to two-agent BM perception. We then investigated how this response was modulated by the interaction of two agents. In the present experiment, we presented two kinds of visual stimuli (interacting and non-interacting BM) with two orientations (upright and inverted).
Results: We found a neuromagnetic response in the bilateral occipitotemporal region, on average 300-400 ms after the onset of a two-agent BM stimulus. This result showed that interhemispheric differences were apparent for the peak amplitudes. For the left hemisphere, the orientation effect was manifest when the two agents were made to interact, and the interaction effect was manifest when the stimulus was inverted. In the right hemisphere, the main effects of both orientation and interaction were significant, suggesting that the peak amplitude was attenuated when the visual stimulus was inverted or made to interact.
Conclusion: These results demonstrate that the 'interaction' information of two agents can affect the neural activities in the bilateral occipitotemporal region, on average 300-400 ms after the onset of a two-agent BM stimulus, however, the modulation was different between hemispheres: the left hemisphere is more concerned with dynamics, whereas the right hemisphere is more concerned with form information.

DOI： 10.1186/1471-2202-10-39

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.neuroscience.2008.12.014

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1057/WNR.0B013e32832000de

Language：Japanese   Publishing type：Research paper (scientific journal)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ASSOC RESEARCH VISION OPHTHALMOLOGY INC  

To reveal the neural dynamics underlying biological motion processing, we introduced a novel golf-swing point-light motion (PLM) stimulus with an adaptation paradigm and measured event-related potentials (ERPs). In the adaptation phase, PLM and scrambled PLM (sPLM) stimuli were presented
a static point-lights stimulus was also presented as a control condition. In the subsequent test phase, PLM or sPLM stimuli were presented. We measured ERPs from the onset of the test phase. Two negative components were observed and modulated differently: the amplitude of the N1 component was significantly attenuated by PLM and sPLM adaptation stimuli compared with the static point-light adaptation stimulus, whereas the amplitude of the N2 component in response to the PLM test stimulus was significantly attenuated only by the PLM adaptation stimulus. The amplitude of the N2 component in response to the PLM test stimulus was significantly larger than that in response to the sPLM test stimulus when a sPLM or static adaptation stimulus was used. These findings indicate that the N1 component is sensitive to local motion information while the N2 component is sensitive to the presence of a coherent form conveyed by global motion. © ARVO.

DOI： 10.1167/8.16.2

Web of Science

Scopus

PubMed

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.clinph.2008.09.008

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.brainresbull.2008.08.011

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.neuroimage.2008.05.017

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.brainres.2007.05.078

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

To investigate the neural response to detection of biological motion (BM) surrounded by distractors, event-related potentials (ERPs) were recorded. Scrambled motion with the same velocity vector as the BM but randomized initial starting points was used as the distractor. The number of distractors was varied to control the difficulty of the task. The behavioral data showed that the reaction time increased with the number of distractors. Moreover, the ERP results showed that enhanced negativity was elicited at posterior electrodes contralateral to the location of the BM as with the conventional N2pc-like component, which is related to selection of the target. The increment of reaction time indicated that the attentional process is involved in the detection of BM. Furthermore, the ERP waveforms suggest that, even when detection of the target requires form-from-motion processing, similar neural mechanisms to those involved in conventional visual search tasks were employed here. © 2006 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.neulet.2006.05.002

Scopus

PubMed

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

We investigated how the spatiotemporal structure of animations of biological motion (BM) affects brain activity. We measured event-related potentials (ERPs) during the perception of BM under four conditions: normal spatial and temporal structure; scrambled spatial and normal temporal structure; normal spatial and scrambled temporal structure; and scrambled spatial and temporal structure. As in a previous study, we identified two negative components at both occipitotemporal regions: N210 reflected general motion processing while N280 reflected the processing of BM. We analyzed the averaged ERPs in the 200-300 ms response time window and found that spatial structure had a substantial effect on the magnitude of the averaged response amplitude in both hemispheres. This finding suggests that spatial structure of point-lights elicits a stronger response in the occipitotemporal region than temporal structure for the BM perception. (C) 2005 Published by Elsevier B.V.

DOI： 10.1016/j.cognition.2005.05.003

Web of Science

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.cogbrainres.2004.08.008

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.cogbrainres.2004.11.005

Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

To clarify the neural dynamics in human motor imitation, we examined event-related potentials (ERP) for a reaction time task that required responses to an actor's finger motions with identical motions. Compared with a control task (reaction to an LED illumination), the ERP surface topography in the imitative reaction was differentiated at around 120-200 ms post-cueing, showing an early sensitivity to the response hand over the pre-central region. This result suggested that activities around the motor areas were facilitated in the imitative reaction, which is consistent with recent neuroimaging studies. However, taken together with that there were no differences in reaction times, the early ERP latency of conditional divergence indicated that neural activities related to imitation are visual responses and do not directly lead to motor acceleration.

DOI： 10.1097/00001756-200409150-00026

Web of Science

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI IRELAND LTD  

In order to clarify the neural dynamics involved in the perception of biological motion, we recorded event-related potentials from 12 subjects. The subjects were shown biological motion or scrambled motion as a control stimulus. In the scrambled motion, each point had the same velocity vector as in the biological motion, but the initial starting positions were randomized. The perception of both biological and scrambled motion elicited negative peaks at around 200 (N200) and 240 ms (N240). Furthermore, both negative peaks were significantly larger in the biological motion condition than in the scrambled motion condition over the right occipitotemporal region. In light of previous human neuroimaging studies, we speculate that component N200 is generated near the extrastriate cortex area and N240 is generated from the superior temporal sulcus region. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved.

DOI： 10.1016/S0304-3940(03)00413-0

Web of Science