Comparison of the Sensory Profile Among Autistic Individuals and Individuals with Williams Syndrome.

PURPOSE: With the current study, we aimed to reveal the similarities and differences in sensory profiles between Williams syndrome (WS) and autism spectrum disorder. METHODS: Using the sensory profile questionnaire completed by the caregivers, we analyzed the WS (n = 60, 3.4-19.8 years) and autistic (n = 39, 4.2-14.0 years) groups. RESULTS: The Severity Analysis revealed a significant group difference in Sensory Sensitivity but not in Low Registration, Sensation Seeking, and Sensation Avoiding subscales. Age can modulate the subscale scores differently across groups. For Sensation Seeking, the scores of both groups decreased with development. However, the scores of Sensory Sensitivity decreased with age in the autistic group but not in the WS group. Sensation Avoiding scores increased with development in the WS group but not in the autistic group. No significant developmental changes were observed in Low Registration. CONCLUSION: This study highlights the cross-syndrome similarities and differences in sensory profiles and developmental changes in autistic individuals and individuals with WS.

Development of emotion comprehension in children with autism spectrum disorder and Williams syndrome.

Although research has shed light on the development of emotion comprehension in typically developing children, little is known about emotion comprehension in children who are developing atypically. Thus, this study examined the developmental trajectory of emotion understanding in non-clinical (NC) children and children with autism spectrum disorder (ASD) and Williams syndrome (WS) using a Test of Emotion Comprehension. In the test, we measured children's understanding of (I) recognition of emotions based on facial expressions, (II) external causes of emotions, (III) desire-based emotions, (IV) belief-based emotions, (V) the influence of a reminder on a present emotional state, (VI) regulating an experienced emotion, (VII) hiding an emotional state, (VIII) mixed emotions, and (IX) moral emotions. A Bayesian modeling approach was applied to compare the developmental trajectories of emotion understanding across the syndrome groups. The results revealed that NC children and children with WS followed significantly different developmental trajectories in specific aspects of emotion understanding, while children with ASD followed a very similar path to NC children. Children with ASD and NC children gradually developed an understanding of each component of emotion comprehension as they matured. However, the understanding of some components, such as desire-based emotions, hiding an emotional state, and moral emotions, in children with WS was affected by their Autism Spectrum Quotient scores. This is one of the first cross-syndrome studies to assess the development of emotion comprehension in children with ASD and WS, providing important insights for understanding the nature of disability and advancing the development of intervention programs.

Autistic traits associated with dichotomic thinking mediated by intolerance of uncertainty.

A recent cognitive model suggests that autistic individuals may experience dichotomous thinking patterns mediated by intolerance of uncertainty; however, empirical evidence to support this model is lacking. This study aimed to identify the relationships between autistic traits, intolerance of uncertainty, and dichotomous thinking using the Autism Spectrum Quotient, Short Intolerance of Uncertainty Scale, and the Dichotomous Thinking Inventory. We collected data from non-clinical university students (N = 151; pilot study) and general adults (N = 500; main study) and analyzed the results using structural equation modeling. Both studies showed a significant indirect effect of autistic traits on dichotomous thinking mediated by intolerance of uncertainty. Moreover, the results indicated that intolerance of uncertainty was significantly and positively associated with Autism Spectrum Quotient and Dichotomous Thinking Inventory scores. Conversely, there was a significant negative direct association between Autism Spectrum Quotient and Dichotomous Thinking Inventory scores. This is the first study to demonstrate that autistic traits can result in dichotomous thinking through intolerance of uncertainty. These findings provide insight into the cognitive patterns of autistic individuals.

Comparison of the Social Responsiveness Scale-2 among Individuals with Autism Spectrum Disorder and Williams Syndrome in Japan.

This study examined the similarities/differences between the social phenotypes of Williams syndrome (WS) and autism spectrum disorder (ASD). As cultural norms may affect symptom evaluation, this study administered the Social Responsiveness Scale-2 to Japanese individuals with WS (n = 78, 4.4-44.0 years) and ASD (n = 75, 4.7-55.4 years). The scores for Social Motivation and Social Communication were significantly more severe in the ASD than WS group. Overall, the similarities and differences between the social phenotypes of the syndromes were consistent with the findings of a recent study conducted in the UK, except for the social awareness subscale score. This highlights the importance of cross-cultural investigations of WS and ASD.

Electrophysiological evidence of global structure-from-motion processing of biological motion in 6-month-old infants.

Understanding the actions of others is a fundamental and important skill for navigating our social world. A striking example of how our visual system is sensitive to others' actions is the phenomenon of biological motion (BM), in which the visual system encodes socially relevant information regarding action from as few as a dozen point-lights of motion. Previous studies have demonstrated that infants can discriminate between BM and other types of actions. However, there is a lack of electrophysiological evidence outlining the exact point of time within the first year of life when global structure-from-motion processing of BM emerges. We herein show a clear event-related potential (ERP) response related to the global structure-from-motion processing of a coherent human point-light walker in 6-month-old infants. We introduced a novel experimental paradigm composed of two stimuli phases to extract a single ERP component related to the global structure-from-motion processing of a coherent human point-light walker. Furthermore, we demonstrated that an enhanced single ERP component observed at approximately 482-586 ms following the onset of the stimulus of a coherent human point-light walker was larger than that of a spatially scrambled point-light walker in 6-month-old infants. These findings suggest that 6-month-old infants can process the global structure-from-motion information of a coherent human point-light walker, which may involve the posterior part of the superior temporal sulcus region. The current findings further refine the recently outlined developmental theory of BM processing.

Visual perspective-taking ability in 7- and 12-month-old infants.

Understanding how we see the world is different from how other people see it is a crucial part of social cognition and is known as visual perspective-taking. Although previous studies have demonstrated that 14-month-old infants have the capacity to compute the visual perspectives of others, it remains unknown whether infants under 12 months also have this ability. In this study, we modified a conventional gaze-following experimental setting in which one toy was placed in front of a model and was hidden by a barrier (Blocked Line of Sight Condition), and another toy was placed without a barrier (Clear Line of Sight Condition). We examined the visual perspective-taking abilities of 48 infants aged 7 and 12 months by measuring the infants' gaze shift towards the gaze-cued toy object with and without a barrier. The results demonstrated that 12-month-old infants could correctly follow a model's gaze if the model's line of sight was clear. In contrast, 7-month-old infants showed no evidence of such capacity. Our findings indicate that 12-month-old infants seem to have the capacity to compute the visual perspective of others.

Developmental changes of the neural mechanisms underlying level 2 visual perspective-taking: A functional near-infrared spectroscopy study.

The ability to understand the way other people see the world differs from one's own viewpoint is referred to as ''visual perspective-taking'' (VPT). Previous studies have demonstrated the behavioral performance in level 2 VPT (VPT2), the ability to understand that two different observers can have unique visual experiences of the same scene or object depending on the observers' physical location, changes during childhood. However, the developmental aspects underlying the neural mechanisms of VPT2 remains unknown. We measured the hemodynamic responses to a VPT2 task using functional near-infrared spectroscopy, with mental rotation (MR) as a control task in 7- to 11-year-old and 11- to 16-year-old groups. In the VPT2 task, participants were required to mentally compute the perspective of a toy on the turntable from that of a doll placed in a different location from the observer. For the MR task, participants reported their perspectives after the toy was rotated. We found significantly higher oxy-hemoglobin changes during the VPT2 task than the MR task in the 7- to 11-year-old group but not in the 11- to 16-year-old group, in the right middle and superior temporal, angular gyrus and frontal regions. These findings highlight the important role of the right temporoparietal region in processing perspective, up to 11 years.

Observing inefficient action can induce infant preference and learning.

'Motionese' can be defined as an exaggerated and repetitive action. It induces preference and learning in infants. However, which action component of motionese promotes infants' preference and learning remains largely unknown. In this study, we focused on inefficiency and toward-ness of action. Our study demonstrates that observing an inefficient holding out action can induce a visual preference in 4-month-old infants and learning in 10-month-old infants through eight experiments (N = 192). We found that when infants observe inefficient holding out action, the action attracts their attention and facilitates learning about the identity of the toy object accompanying it, especially when people direct inefficient actions towards them. Our findings indicate that both action efficiency and toward-ness may be key factors in infant learning.

Greater reliance on proprioceptive information during a reaching task with perspective manipulation among children with autism spectrum disorders.

Difficulties with visual perspective-taking among individuals with autism spectrum disorders remain poorly understood. Many studies have presumed that first-person visual input can be mentally transformed to a third-person perspective during visual perspective-taking tasks; however, existing research has not fully revealed the computational strategy used by those with autism spectrum disorders for taking another person's perspective. In this study, we designed a novel approach to test a strategy using the opposite-directional effect among children with autism spectrum disorders. This effect refers to how a third-person perspective as a visual input alters a cognitive process. We directly manipulated participants' visual perspective by placing a camera at different positions; participants could watch themselves from a third-person perspective during a reaching task with no endpoint feedback. During a baseline task, endpoint bias (with endpoint feedback but no visual transformation) did not differ significantly between groups. However, the endpoint was affected by extrinsic coordinate information in the control group relative to the autism spectrum disorders group when the visual perspective was transformed. These results indicate an increased reliance on proprioception during the reaching task with perspective manipulation in the autism spectrum disorders group.

Does culture shape face perception in autism? Cross-cultural evidence of the own-race advantage from the UK and Japan.

Autism spectrum disorders (ASD) are associated with face perception atypicalities, and atypical experience with faces has been proposed as an underlying explanation. Studying the own-race advantage (ORA) for face recognition can reveal the effect of experience on face perception in ASD, although the small number of studies in the area present mixed findings. This study probed the ORA in ASD by comparing two cultural groups simultaneously for the first time. Children with ASD in the UK (N = 16) and Japan (N = 26) were compared with age- and ability-matched typically developing (TD) children in the UK (N = 16) and Japan (N = 26). Participants completed a two-alternative forced-choice task, whereby they had to recognize a just seen face from a foil which was manipulated in one of four ways (IC: identity change; EE: easy eyes; HE: hard eyes; HM: hard mouth). Face stimuli were Asian and Caucasian, and thus the same stimuli were own and other race depending on the cultural group. The ASD groups in the UK and Japan did not show impaired face recognition abilities, or impairments with recognizing faces depending on manipulations to the eye region, and importantly they showed an ORA. There was considerable heterogeneity in the presence of the ORA in ASD and TD and also across cultures. Children in Japan had higher accuracy than children in the UK, and TD children in Japan did not show an ORA. This cross-cultural study challenges the view that atypical experiences with faces lead to a reduced/absent ORA in ASD.

The two-process theory of biological motion processing.

Perception, identification, and understanding of others' actions from motion information are vital for our survival in the social world. A breakthrough in the understanding of action perception was the discovery that our visual system is sensitive to human action from the sparse motion input of only a dozen point lights, a phenomenon known as biological motion (BM) processing. Previous psychological and computational models cannot fully explain the emerging evidence for the existence of BM processing during early ontogeny. Here, we propose a two-process model of the mechanisms underlying BM processing. We hypothesize that the first system, the 'Step Detector,' rapidly processes the local foot motion and feet-below-the-body information that is specific to vertebrates, is less dependent on postnatal learning, and involves subcortical networks. The second system, the 'Bodily Action Evaluator,' slowly processes the fine global structure-from-motion, is specific to conspecific, and dependent on gradual learning processed in cortical networks. This proposed model provides new insight into research on the development of BM processing.

Role of the Embodied Cognition Process in Perspective-Taking Ability During Childhood.

This study examined developmental changes in Level-2 visual perspective taking (VPT2) in 90 children aged 4-12 years and tested the role of their ability to mentally simulate changes to their bodily locations (self-motion imagery; SMI). Performance of a mental toy rotation task and a self-motion (SM) task (changing location of children) was superior to that of VPT2 and SMI tasks. Task performance of SMI was better than that of VPT2 before 10;0 (years;months). Furthermore, egocentric responses in VPT2 and SMI tasks were significantly more frequent than those in the mental rotation and SM tasks before 10;3. These findings suggest the involvement of embodied cognitive processes in perspective taking and the advantage of utilizing bodily information by age 10.

Prefrontal activity predicts individual differences in optimal attentional strategy for preventing motor performance decline: a functional near-infrared spectroscopy study.

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.

Face-to-trait inferences in patients with Parkinson's disease.

Introduction: Parkinson's disease is a progressive neurological disorder characterized by the preferential loss of dopaminergic neurons in the substantia nigra, which project to the striatum. The disease is characterized by prominent motor symptoms, which are its cardinal features. Consequently, Parkinson's disease has been primarily considered a disorder of movement. However, increasing evidence has indicated that Parkinson's disease affects not only the motor domain but also the cognitive domain. Increasing evidence indicates that patients with Parkinson's disease have an impaired ability to recognize emotional facial expressions. Recent studies have reported that other socially relevant information from faces, including face-to-trait inferences for traits such as dominance, competence, and trustworthiness, may be processed in subcortical regions, including the amygdala and caudate nucleus. However, the mechanism underlying the processing of face-to-trait inferences for these traits in patients with Parkinson's disease is still unknown. This study aimed to assess the face-to-trait inference ability in patients with Parkinson's disease. Method: Face-to-trait inference ability was assessed using a forced-choice method in patients with Parkinson's disease and age- and sex-matched healthy controls. Results: Overall correct face-to-trait inferences occurred significantly less frequently in the Parkinson's disease group than in the control group. Further analysis revealed a significant interaction between groups and the extent to which facial features were exaggerated. Conclusions: The present results suggest that the sensitivity of face-to-trait processing was linear in the Parkinson's disease group but not in the healthy controls. These deficits may have resulted from dysfunction in subcortical regions, which may also lead to impairment in other social inferential abilities in patients with Parkinson's disease.

Communicative hand-waving gestures facilitate object learning in preverbal infants.

The theory of natural pedagogy has proposed that infants can use ostensive signals, including eye contact, infant-directed speech, and contingency to learn from others. However, the role of bodily gestures, such as hand-waving, in social learning has been largely ignored. To address this gap in the literature, this study sought to determine whether 4-month-old infants exhibited a preference for horizontal or vertical (control) hand-waving gestures. We also examined whether horizontal hand-waving gestures followed by pointing facilitated the process of object learning in 9-month-old infants. Results showed that 4-month-old infants preferred horizontal hand-waving gestures to vertical hand-waving gestures, even when featural and contextual information were removed. Furthermore, horizontal hand-waving gestures induced identity encoding for cued objects, whereas vertical gestures did not. These findings highlight the role of communicative intent embedded in bodily movements and indicate that hand-waving can serve as a new type of ostensive signal.

Individual optimal attentional strategy during implicit motor learning boosts frontoparietal neural processing efficiency: A functional near-infrared spectroscopy study.

INTRODUCTION: Optimal focus of attention is a crucial factor for improving motor learning. Most previous studies have shown that directing attention to movement outcome (external focus; EF) is more effective than directing attention to body movement itself (internal focus; IF). However, our recent studies demonstrated that the optimal attentional strategy in healthy and clinical populations varies depending on individual motor imagery ability. To explore the neurological basis underlying individual optimal attentional strategy during motor learning tasks, in the present study, we measured frontoparietal activities using functional near-infrared spectroscopy (fNIRS). METHODS: Twenty-eight participants performed a visuomotor learning task requiring circular tracking. During the task, the participants were required to direct their attention internally or externally. The individual optimal attentional strategy was determined by comparing the after-effect sizes between the IF and EF conditions. RESULTS: Fifteen participants showed larger after-effects under the EF condition (External-dominant), whereas the others showed larger after-effects under the IF condition (Internal-dominant). Based on the differences in neural activities between Internal- and External-dominant groups, we identified the right dorsolateral prefrontal cortex (Brodmann area 46) and right somatosensory association cortex (Brodmann area 7) as the neural bases associated with individual optimal attentional strategy during motor learning. Furthermore, we observed a significant negative correlation, that is, lower activity in these areas was associated with a larger after-effect size under the optimal attentional strategy. CONCLUSION: Our findings demonstrated that more efficient neural processing in the frontoparietal area under the individual optimal attentional strategy can accelerate motor learning.

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.

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.

Probing links between action perception and action production in Parkinson's disease using Fitts' law.

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.

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.

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.