The integration of occlusion and disparity information for judging depth in autism spectrum disorder

In autism spectrum disorder (ASD), atypical integration of visual depth cues may be due to flattened perceptual priors or selective fusion. The current study attempts to disentangle these explanations by psychophysically assessing within-modality integration of ordinal (occlusion) and metric (disparity) depth cues while accounting for sensitivity to stereoscopic information. Participants included 22 individuals with ASD and 23 typically developing matched controls. Although adults with ASD were found to have significantly poorer stereoacuity, they were still able to automatically integrate conflicting depth cues, lending support to the idea that priors are intact in ASD. However, dissimilarities in response speed variability between the ASD and TD groups suggests that there may be differences in the perceptual decision-making aspect of the task

The Social Modulation of Imitation Fidelity in School-Age Children

Children copy the actions of others with high fidelity, even when they are not causally relevant. This copying of visibly unnecessary actions is termed overimitation. Many competing theories propose mechanisms for overimitation behaviour. The present study examines these theories by studying the social factors that lead children to overimitate actions. Ninety-four children aged 5- to 8-years each completed five trials of an overimitation task. Each trial provided the opportunity to overimitate an action on familiar objects with minimal causal reasoning demands. Social cues (live or video demonstration) and eye contact from the demonstrator were manipulated. After the imitation, children's ratings of action rationality were collected. Substantial overimitation was seen which increased with age. In older children, overimitation was higher when watching a live demonstrator and when eye contact was absent. Actions rated as irrational were more likely to be imitated than those rated as rational. Children overimitated actions on familiar objects even when they rated those actions as irrational, suggesting that failure of causal reasoning cannot be driving overimitation. Our data support social explanations of overimitation and show that the influence of social factors increases with age over the 5- to 8-year-old age range

Perceptual processing in individuals with autism

The aim of this thesis was to explore perceptual processing in individuals with autism and Asperger's syndrome, and to assess the extent to which the theory of weak central coherence could account for any abnormalities in this area. In Experiment 3:1 we presented individuals with autism with four illusions on a computer and asked them to adjust certain parts to appear the same. The results showed just as susceptible to illusions as those without autism on a computer task contrary to previous literature (Happe, 1996). In Experiment 3:2 we presented the same illusions on card and asked participants to judge whether parts of the stimuli were the same or different as in Happe's procedure. Our results showed that autistic populations succumbed to illusions regardless of whether they verbally judged or manually made adjustments to the stimuli. This ruled out the possibility that procedural differences could account for our failure to replicate Happe's findings. These results show that coherence is intact at low levels of perceptual processing in autism. Our second study (Experiment 4:1) explored whether individual differences in coherence may be able to explain why the results of Experiments 3:1 and 3:2 were not consistent with Happe's findings. We presented a battery of visuo-spatial tasks (block design, embedded figures, Rey complex figure test) and the visual illusion computer task to participants. Performance on these tasks was unable to predict susceptibility to visual illusions, suggesting that perception of illusions may not be related to weak central coherence. Our final investigation explored whether autistic populations were more inclined to rely on visual rather than semantic properties when asked to pair atypically coloured pictures (e. g. blue banana) with colour patches (e. g. yellow or blue). Those with autism relied on background knowledge like control participants choosing the semantically related colour. We then considered whether requiring the participants to name the object before selecting a colour may have influenced them to choose the semantic alternative in Experiment 5:2. Those with autism performed similarly to comparison groups choosing the semantic rather than the visual option. This demonstrated that background knowledge was just as salient to those with autism and Asperger's syndrome as those without autism

Social seeking declines in young adolescents

The desire to engage with others is an important motivational force throughout our lifespan. It is known that social behaviour and preferences change from childhood to adulthood, but whether this change is linked with any changes in social motivation is not known. We evaluated 255 typically developing participants from ages 4–20 years on a behavioural paradigm ‘Choose a Movie’ (CAM). On every trial, participants had a choice between viewing social or non-social movies presented with different levels of effort (key presses/screen touch required). Hence, participants chose not only the movie they would watch but also how much effort they would make. The difference between the effort levels of the chosen and not chosen stimuli helps in quantifying the motivation to seek it. This task could be used with all the age groups with minimal adaptations, allowing comparison between the groups. Results showed that children (4–8 years), older adolescents (12–16 years) and young adults (17–20 years) made more effort to look at social movies. Counterintuitively, this preference was not seen in young adolescents (around 9–12 years), giving a U-shaped developmental trajectory over the population. We present the first evidence for non-monotonic developmental change in social motivation in typical participants

The integration of occlusion and disparity information for judging depth in autism spectrum disorder

In autism spectrum disorder (ASD), atypical integration of visual depth cues may be due to flattened perceptual priors or selective fusion. The current study attempts to disentangle these explanations by psychophysically assessing within-modality integration of ordinal (occlusion) and metric (disparity) depth cues while accounting for sensitivity to stereoscopic information. Participants included 22 individuals with ASD and 23 typically developing matched controls. Although adults with ASD were found to have significantly poorer stereoacuity, they were still able to automatically integrate conflicting depth cues, lending support to the idea that priors are intact in ASD. However, dissimilarities in response speed variability between the ASD and TD groups suggests that there may be differences in the perceptual decision-making aspect of the task

The Anxiety Caused by Secondary Schools for Autistic Adolescents: In Their Own Words

Secondary schools are increasingly becoming inclusive of all students whatever their individual needs, but we question whether teachers understand enough about specific needs in order to effectively support all their students. Research indicates that autistic students often struggle with aspects of school (conformity; social communication; sensory challenges; bullying) but very few studies ask autistic adolescents about their experiences. One of the key elements of the school experience for autistic adolescents is the levels of anxiety experienced by many students on a daily basis. This research set out to explore the extent to which autistic students in secondary schools in the UK were able to recognise and reflect on their own anxiety. The eighteen participants in this co-produced qualitative study took part in semi-structured interviews planned by a team of autistic and non-autistic researchers. The themes that emerged from this study, in terms of triggers for anxiety, included other people’s behaviour, fear of the unknown, and sensory sensitivities. A theoretical view of their difficulties concurs with the concept of intolerance of uncertainty. Our data suggest that autistic students continue to experience high levels of anxiety throughout their secondary education, despite supports put in place by some schools. Strategies are highlighted that could be implemented by all schools to promote truly inclusive settings

Prevalence of Victimisation in Autistic Individuals: A Systematic Review and Meta-Analysis

Autistic individuals are at an increased risk of experiencing victimisation. Previous reviews have focussed specific types of victimisation. Thus, a clearer picture considering the range of victimisation experiences autistic people face is required. This systematic review aims to identify the prevalence of victimisation in autistic individuals considering a variety of victimisation types (e.g., bulling, sexual victimisation, and crime) in both adults and children from clinical and community settings. Through systematic searches of relevant databases, 291 studies met the criteria for review. Of those, 34 studies met the inclusion criteria: a) quantitative studies, b) involving autistic individuals, c) reporting prevalence rates of victimisation. Meta-analysis found a pooled prevalence rate of victimisation of 44% in autistic individuals. Subgroup analysis examined moderating factors as high heterogeneity was present. This found the pooled prevalence rates for bullying to be 47%, 16% for child abuse, 40% for sexual victimisation, 13% for cyberbullying, and 84% for multiple forms of victimisation in autistic individuals, though heterogeneity remained. Correction for participants’ age, reporter used, and the population which the sample was recruited from did not reduce heterogeneity. Although heterogeneity impedes the definitive interpretation of the findings, this review illustrates the need for strategies and interventions to reduce the incidence of victimisation

Are you watching me?: the role of audience and object novelty on overimitation

This study tests whether overimitation is subject to an audience effect, and whether it is modulated by object novelty. Eighty-six 4-to-11-year old children watched a demonstrator open novel and familiar boxes, using sequences of necessary and unnecessary actions. The experimenter then observed the child, turned away, or left the room while the child opened the box. Children copied unnecessary actions more when the experimenter watched or when she left, but copied less when she turned away. This parallels infant studies which suggest that turning away is interpreted as a signal of disengagement. Children displayed increased overimitation and reduced efficiency discrimination when opening novel, compared to familiar boxes. These data provide important evidence that object novelty is a critical component of overimitation