Longitudinal study of personal space in autism.

The size and regulation of personal space are reportedly atypical in autistic individuals. As personal space regulates social interaction, its developmental change is essential for understanding the nature of social difficulties that autistic individuals face. Adolescence is an important developmental period in which social relationships become complex. We conducted a three-year longitudinal study of interpersonal distances in autistic and typically developing (TD) individuals aged 12-18 years at Time 1 and 15-21 years at Time 2. Their preferred interpersonal distances were measured when an experimenter approached the participants with and without eye contact. The interpersonal distances of autistic individuals were shorter than those of TD individuals at both Time 1 and Time 2. Furthermore, the interpersonal distances of autistic individuals at Time 1 and Time 2 were highly correlated, but no such correlation was found in TD individuals. The results suggest that the interpersonal distances of autistic individuals are stable and that the shorter preferred interpersonal distances in autistic individuals compared to those of TD individuals are maintained during adolescence.

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.

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.

Brief Report: Body Image in Autism: Evidence from Body Size Estimation.

Individuals with autism spectrum disorder (ASD) have difficulties with social interaction and communication. First-hand accounts written by individuals with ASD have shown the existence of other atypical characteristics such as difficulties with body awareness. However, few studies have examined whether such atypicalities are found more generally among individuals with ASD. We examined body image (i.e., self-body awareness) by asking individuals with ASD and typically developing (TD) individuals to estimate their own body size (shoulder width). Results show that TD individuals estimated their shoulder width more accurately than individuals with ASD. This study suggests that individuals with ASD often experience misperceptions in their body size.

Publisher Correction: Autonomic versus perceptual accounts for tactile hypersensitivity in autism spectrum disorder.

A correction to this article has been published and is linked from the HTML version of this paper. The error has been fixed in the paper.

Autonomic versus perceptual accounts for tactile hypersensitivity in autism spectrum disorder.

Tactile atypicality in individuals with autism spectrum disorder (ASD) has harmful effects on their everyday lives including social interactions. However, whether tactile atypicality in ASD reflects perceptual and/or autonomic processes is unknown. Here, we show that adults with ASD have hypersensitivity to tactile stimuli in the autonomic but not perceptual domain. In particular, adults with ASD showed a greater skin conductance response (SCR) to tactile stimuli compared to typically developing (TD) adults, despite an absence of differences in subjective responses. Furthermore, the level of the SCR was correlated with sensory sensitivity in daily living. By contrast, in perceptual discriminative tasks that psychophysically measured thresholds to tactile stimuli, no differences were found between the ASD and TD groups. These results favor the hypothesis that atypical autonomic processing underlies tactile hypersensitivity in ASD.

Reduced Personal Space in Individuals with Autism Spectrum Disorder.

Maintaining an appropriate distance from others is important for establishing effective communication and good interpersonal relations. Autism spectrum disorder (ASD) is a developmental disorder associated with social difficulties, and it is thus worth examining whether individuals with ASD maintain typical or atypical degrees of social distance. Any atypicality of social distancing may impact daily social interactions. We measured the preferred distances when individuals with ASD and typically developing (TD) individuals approached other people (a male experimenter) and objects (a coat rack with clothes) or when other people approached them. Individuals with ASD showed reduced interpersonal distances compared to TD individuals. The same tendency was found when participants judged their preferred distance from objects. In addition, when being approached by other people, both individuals with ASD and TD individuals maintained larger interpersonal distances when there was eye contact, compared to no eye contact. These results suggest that individuals with ASD have a relatively small personal space, and that this atypicality exists not only for persons but also for objects.

Atypical delayed auditory feedback effect and Lombard effect on speech production in high-functioning adults with autism spectrum disorder.

Individuals with autism spectrum disorder (ASD) show impaired social interaction and communication, which may be related to their difficulties in speech production. To investigate the mechanisms of atypical speech production in this population, we examined feedback control by delaying the auditory feedback of their own speech, which degraded speech fluency. We also examined feedforward control by adding loud pink noise to the auditory feedback, which led to increased vocal effort in producing speech. The results of Japanese speakers show that, compared with neurotypical (NT) individuals, high-functioning adults with ASD (including Asperger's disorder, autistic disorder, and pervasive developmental disorder not otherwise specified) were more affected by delayed auditory feedback but less affected by external noise. These findings indicate that, in contrast to NT individuals, those with ASD relied more on feedback control than on feedforward control in speech production, which is consistent with the hypothesis that this population exhibits attenuated Bayesian priors.

Understanding violations of Gricean maxims in preschoolers and adults.

This study used a revised Conversational Violations Test to examine Gricean maxim violations in 4- to 6-year-old Japanese children and adults. Participants' understanding of the following maxims was assessed: be informative (first maxim of quantity), avoid redundancy (second maxim of quantity), be truthful (maxim of quality), be relevant (maxim of relation), avoid ambiguity (second maxim of manner), and be polite (maxim of politeness). Sensitivity to violations of Gricean maxims increased with age: 4-year-olds' understanding of maxims was near chance, 5-year-olds understood some maxims (first maxim of quantity and maxims of quality, relation, and manner), and 6-year-olds and adults understood all maxims. Preschoolers acquired the maxim of relation first and had the greatest difficulty understanding the second maxim of quantity. Children and adults differed in their comprehension of the maxim of politeness. The development of the pragmatic understanding of Gricean maxims and implications for the construction of developmental tasks from early childhood to adulthood are discussed.

Social phenotypes of autism spectrum disorders and williams syndrome: similarities and differences.

Autism spectrum disorders (ASD) and Williams syndrome (WS) both are neurodevelopmental disorders, each with a unique social phenotypic pattern. This review article aims to define the similarities and differences between the social phenotypes of ASD and WS. We review studies that have examined individuals with WS using diagnostic assessments such as the Autism Diagnostic Observation Schedule (ADOS), cross-syndrome direct comparison studies, and studies that have individually examined either disorder. We conclude that (1) individuals with these disorders show quite contrasting phenotypes for face processing (i.e., preference to faces and eyes) and sociability (i.e., interest in and motivation to interact with others), and (2) although the ADOS and a direct comparison study on pragmatic language ability suggest more deficits in ASD, individuals with WS are similarly impaired on social cognition and communicative skills. In light of these results, we discuss how cross-syndrome comparisons between ASD and WS can contribute to developmental theory, cognitive neuroscience, and the development and choice of clinical treatments.

Atypical verbal communication pattern according to others' attention in children with Williams syndrome.

Children with Williams syndrome (WS) have been reported to often face problems in daily communication and to have deficits in their pragmatic language abilities. To test this hypothesis, we examined whether children with WS could modify their verbal communication according to others' attention in order to share what they did. The children with WS and typically developing (TD) children were asked to accomplish tasks as quickly as possible while the experimenter was attending to or not attending to them during and after their accomplishment. The results showed that although TD children verbalized more when they were not attended to than attended to, children with WS verbalized more when they were attended to than not attended to. The results indicate that children with WS may have deficits in attention-sharing communication, suggesting a part of their pragmatic abilities is impaired.