Visuo-spatial performance in autism: a meta-analysis

Visual mental imagery abilities in autism

In autistic individuals, the role, performance, and autonomy of perceptual functioning are atypical. Overlapping underlying mechanisms of perception and mental imagery predict that the mental imagery abilities of autistic individuals should differ from those of non‐autistic individuals. While enhanced abilities to manipulate mental images have been demonstrated in autism, the other stages of mental imagery (generation, maintenance, inspection) remain to be explored. Forty‐four autistic adults and 42 typical participants performed four tasks to assess different stages of mental imagery: the Image generation task (mentally generating a letter on a grid and indicating whether it passes over a probe located in the grid), the Visual pattern test (maintaining visual patterns in memory), the Image scanning test (inspecting mental images) and the Mental rotation test (mentally manipulating representations of geometric figures). In the image generation task and the mental rotation test, autistic and typical individuals performed equivalently, both in accuracy and response time. The span observed in the visual pattern test was significantly higher in the autistic group, indicating better maintenance of mental images. In the image scanning test, response times were influenced by the distance to mentally inspect in the typical group but not in the autistic group. Autistic participants were equally fast regardless of distance to inspect. Preserved, greater or differently influenced visual mental imagery abilities are in line with an atypical perceptual functioning in autism, possibly reflecting an increased weight of perception‐based information relatively to the top‐down effect of knowledge and language‐based influence.

Individual differences in visual search: A systematic review of the link between visual search performance and traits or abilities

Visual search (VS) comprises a class of tasks that we typically perform several times during a day and requires intentionally scanning (with or without moving the eyes) the environment for a specific target (be it an object or a feature) among distractor stimuli. Experimental research in lab-based or real-world settings has offered insight into its underlying neurocognitive mechanisms from a nomothetic point of view. A lesser-known but rapidly growing body of quasi-experimental and correlational research has explored the link between individual differences and VS performance. This combines different research traditions and covers a wide range of individual differences in studies deploying a vast array of VS tasks. As such, it is a challenge to determine whether any associations highlighted in single studies are robust when considering the wider literature. However, clarifying such relationships systematically and comprehensively would help build more accurate models of VS, and it would highlight promising directions for future research. This systematic review provides an up to date and comprehensive synthesis of the existing literature investigating associations between common indices of performance in VS tasks and measures of individual differences mapped onto four categories of cognitive abilities (short-term working memory, fluid reasoning, visual processing and processing speed) and seven categories of traits (Big Five traits, trait anxiety and autistic traits). Consistent associations for both traits (in particular, conscientiousness, autistic traits and trait anxiety - the latter limited to emotional stimuli) and cognitive abilities (particularly visual processing) were identified. Overall, however, informativeness of future studies would benefit from checking and reporting the reliability of all measurement tools, applying multiplicity correction, using complementary techniques, study preregistration and testing why, rather than only if, a robust relation between certain individual differences and VS performance exists.

Mental rotation and language in autism spectrum disorder

Though visuospatial skills are often considered a relative strength in autism spectrum disorder (ASD), unexplained difficulties relative to neurotypical (NT) peers have also been observed. Dissociations between spatial cognition and language skills in ASD may explain these difficulties given that these systems are linked in NT individuals. The current study examined performance on a mental rotation task that systematically varied stimulus features and the degree to which performance was associated with language in ASD relative to NT peers. Participants were children and young adults with ASD and 25 pairwise age- and IQ-matched NT peers (p's>0.53). The mental rotation task involved four conditions: two-dimensional (2D) abstract figures, three-dimensional (3D) abstract figures, 2D common objects, and 3D common objects. Structural language was measured using the grammar subscale from the Test of Language Development: Intermediate adapted for Norwegian. Mixed-effects model results indicated that autistic individuals were less accurate and had slower reaction time across mental rotation task conditions than NT peers. Language was associated with mental rotation accuracy for both groups across conditions, but with reaction time only for the NT group. The current study demonstrated selective associations between language and performance on a classic spatial cognition task in autistic individuals. Namely, there was a dissociation between language and in-the-moment efficiency in the ASD group, and this dissociation may reflect a broader dissociation between visuospatial and language systems.

Autistic traits as a mediator between visual working memory capacity and enhanced performance in visual-perceptual tasks in children with ASD

The present study aimed to identify autistic traits as a mediator between visual working memory capacity and enhanced performance in visual-perceptual tasks in children with ASD. One hundred-forty children, ages 4-6 years, participated in this study (mean age = 5.34 ± 4.11, 98 males). They were recruited from Taiba Specialized Centers for the Care of People with Special Needs in Saudi Arabia. A correlational design was used to identify the mediating role of autistic traits in the relationship between visual working memory capacity and enhanced performance in visual-perceptual tasks in children with ASD. The present study developed a theoretical model that incorporated autistic traits as a mediator between visual working memory capacity and enhanced performance in visual-perceptual tasks in children with ASD. The study findings indicate that: (1) A significant positive correlation exists between autistic traits and visual working memory capacity; (2) A significant positive correlation exists between autistic traits and enhanced performance in visual-perceptual tasks; (3) The relationship between visual working memory capacity and enhanced performance is mediated by autistic traits.

Perceptual Grouping in Autism Spectrum Disorder: An Exploratory Magnetoencephalography Study

Visual information is organised according to visual grouping principles. In visual grouping tasks individuals with ASD have shown equivocal performance. We explored neural correlates of Gestalt grouping in individuals with and without ASD. Neuromagnetic activity of individuals with (15) and without (18) ASD was compared during a visual grouping task testing grouping by proximity versus similarity. Individuals without ASD showed stronger evoked responses with earlier peaks in response to both grouping types indicating an earlier neuronal differentiation between grouping principles in individuals without ASD. In contrast, individuals with ASD showed particularly prolonged processing of grouping by similarity suggesting a high demand of neural resources. The neuronal processing differences found could explain less efficient grouping performance observed behaviourally in ASD.

Motor imagery in autism: a systematic review

Introduction

Motor Imagery (MI) is when an individual imagines performing an action without physically executing that action and is thought to involve similar neural processes used for execution of physical movement. As motor coordination difficulties are common in autistic individuals it is possible that these may affect MI ability. The aim of this systematic review was to assess the current knowledge around MI ability in autistic individuals.

Methods

A systematic search was conducted for articles published before September 2023, following PRISMA guidance. Search engines were PsycINFO, PubMed, Web of Science, Scopus, Wiley Online Library and PsyArXiv. Inclusion criteria included: (a) Original peer-reviewed and pre-print publications; (b) Autistic and a non-autistic group (c) Implicit or explicit imagery tasks (d) Behavioral, neurophysiological or self-rating measures, (e) Written in the English language. Exclusion criteria were (a) Articles only about MI or autism (b) Articles where the autism data is not presented separately (c) Articles on action observation, recognition or imitation only (d) Review articles. A narrative synthesis of the evidence was conducted.

Results

Sixteen studies across fourteen articles were included. Tasks were divided into implicit (unconscious) or explicit (conscious) MI. The implicit tasks used either hand (6) or body (4) rotation tasks. Explicit tasks consisted of perspective taking tasks (3), a questionnaire (1) and explicit instructions to imagine performing a movement (2). A MI strategy was apparent for the hand rotation task in autistic children, although may have been more challenging. Evidence was mixed and inconclusive for the remaining task types due to the varied range of different tasks and, measures conducted and design limitations. Further limitations included a sex bias toward males and the hand rotation task only being conducted in children.

Discussion

There is currently an incomplete understanding of MI ability in autistic individuals. The field would benefit from a battery of fully described implicit and explicit MI tasks, conducted across the same groups of autistic children and adults. Improved knowledge around MI in autistic individuals is important for understanding whether MI techniques may benefit motor coordination in some autistic people.

The Impact of Audio-Visual, Visual and Auditory Cues on Multiple Object Tracking Performance in Children with Autism

Previous studies have documented differences in processing multisensory information by children with autism compared to typically developing children. Furthermore, children with autism have been found to track fewer multiple objects on a screen than those without autism, suggesting reduced attentional control. In the present study, we investigated whether children with autism (n = 33) and children without autism (n = 33) were able to track four target objects moving amongst four indistinguishable distractor objects while sensory cues were presented. During tracking, we presented various types of cues - auditory, visual, or audio-visual or no cues while target objects bounced off the inner boundary of a centralized circle. We found that children with autism tracked fewer targets than children without autism. Furthermore, children without autism showed improved tracking performance in the presence of visual cues, whereas children with autism did not benefit from sensory cues. Whereas multiple object tracking performance improved with increasing age in children without autism, especially when using audio-visual cues, children with autism did not show age-related improvement in tracking. These results are in line with the hypothesis that attention and the ability to integrate sensory cues during tracking are reduced in children with autism. Our findings could contribute valuable insights for designing interventions that incorporate multisensory information.

Autism-Related Differences in Cortical Activation When Observing, Producing, and Imitating Communicative Gestures: An fNIRS Study

Children with autism spectrum disorder (ASD) have difficulties in gestural communication during social interactions. However, the neural mechanisms involved in naturalistic gestural communication remain poorly understood. In this study, cortical activation patterns associated with gestural communication were examined in thirty-two children with and without ASD (mean age: 11.0 years, SE: 0.6 years). Functional near-infrared spectroscopy (fNIRS) was used to record cortical activation while children produced, observed, or imitated communicative gestures. Children with ASD demonstrated more spatial and temporal errors when performing and imitating communicative gestures. Although both typically developing (TD) children and children with ASD showed left-lateralized cortical activation during gesture production, children with ASD showed hyperactivation in the middle/inferior frontal gyrus (MIFG) during observation and imitation, and hypoactivation in the middle/superior temporal gyrus (MSTG) during gesture production compared to their TD peers. More importantly, children with ASD exhibited greater MSTG activation during imitation than during gesture production, suggesting that imitation could be an effective intervention strategy to engage cortical regions crucial for processing and producing gestures. Our study provides valuable insights into the neural mechanisms underlying gestural communication difficulties in ASD, while also identifying potential neurobiomarkers that could serve as objective measures for evaluating intervention effectiveness in children with ASD.

Different levels of visuospatial abilities linked to differential brain correlates underlying visual mental segmentation processes in autism

The neural underpinnings of enhanced locally oriented visual processing that are specific to autistics with a Wechsler's Block Design (BD) peak are largely unknown. Here, we investigated the brain correlates underlying visual segmentation associated with the well-established autistic superior visuospatial abilities in distinct subgroups using functional magnetic resonance imaging. This study included 31 male autistic adults (15 with (AUTp) and 16 without (AUTnp) a BD peak) and 28 male adults with typical development (TYP). Participants completed a computerized adapted BD task with models having low and high perceptual cohesiveness (PC). Despite similar behavioral performances, AUTp and AUTnp showed generally higher occipital activation compared with TYP participants. Compared with both AUTnp and TYP participants, the AUTp group showed enhanced task-related functional connectivity within posterior visuoperceptual regions and decreased functional connectivity between frontal and occipital-temporal regions. A diminished modulation in frontal and parietal regions in response to increased PC was also found in AUTp participants, suggesting heavier reliance on low-level processing of global figures. This study demonstrates that enhanced visual functioning is specific to a cognitive phenotypic subgroup of autistics with superior visuospatial abilities and reinforces the need to address autistic heterogeneity by good cognitive characterization of samples in future studies.

fNIRS-Based Differences in Cortical Activation during Tool Use, Pantomimed Actions, and Meaningless Actions between Children with and without Autism Spectrum Disorder (ASD)

Children with autism spectrum disorder (ASD) have difficulties with tool use and pantomime actions. The current study utilized functional near-infrared spectroscopy (fNIRS) to examine the neural mechanisms underlying these gestural difficulties. Thirty-one children with and without ASD (age (mean ± SE) = 11.0 ± 0.6) completed a naturalistic peg-hammering task using an actual hammer (hammer condition), pantomiming hammering actions (pantomime condition), and performing meaningless actions with similar joint motions (meaningless condition). Children with ASD exhibited poor praxis performance (praxis error: TD = 17.9 ± 1.7; ASD = 27.0 ± 2.6, p < 0.01), which was significantly correlated with their cortical activation (R = 0.257 to 0.543). Both groups showed left-lateralized activation, but children with ASD demonstrated more bilateral activation during all gestural conditions. Compared to typically developing children, children with ASD showed hyperactivation of the inferior parietal lobe and hypoactivation of the middle/inferior frontal and middle/superior temporal regions. Our findings indicate intact technical reasoning (typical left-IPL activation) but atypical visuospatial and proprioceptive processing (hyperactivation of the right IPL) during tool use in children with ASD. These results have important implications for clinicians and researchers, who should focus on facilitating/reducing the burden of visuospatial and proprioceptive processing in children with ASD. Additionally, fNIRS-related biomarkers could be used for early identification through early object play/tool use and to examine neural effects following gesture-based interventions.

Autistic traits are associated with enhanced working memory capacity for abstract visual stimuli

We tested whether the association between autistic traits and enhanced performance in visual-perceptual tasks extends to visual working memory capacity. We predicted that any positive effect of autistic traits on visual working memory performance would be greatest during domain-specific tasks, in which visual resources must be relied upon. We used a visual 'matrix' task, involving recall of black-and-white chequered patterns which increased in size, to establish participants' capacity (span). We assessed 144 young adults' (M = 22.0 years, SD = 2.5) performance on abstract, 'low semantic' versus 'high semantic' task versions. The latter offered multimodal coding due to the availability of long-term memory resources that could supplement visual working memory. Participants also completed measures of autistic traits and trait anxiety. Autistic traits, especially Attention to Detail, Attention Switching, and Communication, positively predicted visual working memory capacity, specifically in the low semantic task, which relies on visual working memory resources. Autistic traits are therefore associated with enhanced processing and recall of visual information. The benefit is removed, however, when multimodal coding may be incorporated, emphasising the visual nature of the benefit. Strengths in focused attention to detail therefore appear to benefit domain-specific visual working memory task performance.

Specific Global-Local Visual Processing Abilities Mediate the Influence of Non-social Autistic-like Traits on Mental Rotation

Inconsistent data are available on mental rotation performance in neurotypicals with high autistic-like traits. Here, we tested whether global-local visual processing abilities mediate the influence of specific autistic-like trait domains (social skill, attention switching, attention-to-detail, communication, and imagination) on mental rotation. Neurotypical participants (N = 128) underwent an assessment of autistic-like traits, a flanker task with hierarchical stimuli, and a mental rotation task. Path analysis showed that Reaction Times on the incongruent/local condition of the flanker task mediated the relationship between attention-to-detail and mental rotation accuracy. These findings indicate that a better capacity of ignoring incongruent global information to identify local information (reduced global interference) in persons with high non-social autistic-like traits, as attention-to-detail, facilitates mental rotation performance.

Faster social attention disengagement in individuals with higher autism traits

INTRODUCTION

Atypical visual and social attention has often been associated with clinically diagnosed autism spectrum disorder (ASD), and with the broader autism phenotype. Atypical social attention is of particular research interest given the importance of facial expressions for social communication, with faces tending to attract and hold attention in neurotypical individuals. In autism, this is not necessarily so, where there is debate about the temporal differences in the ability to disengage attention from a face.

METHOD

Thus, we have used eye-tracking to record saccadic latencies as a measure of time to disengage attention from a central task-irrelevant face before orienting to a newly presented peripheral nonsocial target during a gap-overlap task. Neurotypical participants with higher or lower autism-like traits (AT) completed the task that included central stimuli with varied expressions of facial emotion as well as an inverted face.

RESULTS

High AT participants demonstrated faster saccadic responses to detect the nonsocial target than low AT participants when disengaging attention from a face. Furthermore, faster saccadic responses were recorded when comparing disengagement from upright to inverted faces in low AT but not in high AT participants.

CONCLUSIONS

Together, these results extend findings of atypical social attention disengagement in autism and highlight how differences in attention to faces in the broader autism phenotype can lead to apparently superior task performance under certain conditions. Specifically, autism traits were linked to faster attention orienting to a nonsocial target due to the reduced attentional hold of the task irrelevant face stimuli. The absence of an inversion effect in high AT participants also reinforces the suggestion that they process upright or inverted faces similarly, unlike low AT participants for whom inverted faces are thought to be less socially engaging, thus allowing faster disengagement.

Cognitive and Developmental Functions in Autistic and Non-Autistic Children and Adolescents: Evidence from the Intelligence and Development Scales-2

Autistic individuals often show impairments in cognitive and developmental domains beyond the core symptoms of lower social communication skills and restricted repetitive behaviors. Consequently, the assessment of cognitive and developmental functions constitutes an essential part of the diagnostic evaluation. Yet, evidence on differential validity from intelligence and developmental tests, which are commonly used with autistic individuals, varies widely. In the current study, we investigated the cognitive (i.e., intelligence, executive functions) and developmental (i.e., psychomotor skills, social-emotional skills, basic skills, motivation and attitude, participation during testing) functions of autistic and non-autistic children and adolescents using the Intelligence and Development Scales-2 (IDS-2). We compared 43 autistic (M_age = 12.30 years) with 43 non-autistic (M_age = 12.51 years) participants who were matched for age, sex, and maternal education. Autistic participants showed significantly lower mean values in psychomotor skills, language skills, and the evaluation of participation during testing of the developmental functions compared to the control sample. Our findings highlight that autistic individuals show impairments particularly in motor and language skills using the IDS-2, which therefore merit consideration in autism treatment in addition to the core symptoms and the individuals' intellectual functioning. Moreover, our findings indicate that particularly motor skills might be rather neglected in autism diagnosis and may be worthy of receiving more attention. Nonsignificant group differences in social-emotional skills could have been due to compensatory effects of average cognitive abilities in our autistic sample.

Keeping the balance: Trade-offs between human brain evolution, autism, and schizophrenia

The unique qualities of the human brain are a product of a complex evolutionary process. Evolution, famously described by François Jacob as a “tinkerer,” builds upon existing genetic elements by modifying and repurposing them for new functions. Genetic changes in DNA may lead to the emergence of new genes or cause altered gene expression patterns. Both gene and regulatory element mutations may lead to new functions. Yet, this process may lead to side-effects. An evolutionary trade-off occurs when an otherwise beneficial change, which is important for evolutionary success and is under strong positive selection, concurrently results in a detrimental change in another trait. Pleiotropy occurs when a gene affects multiple traits. Antagonistic pleiotropy is a phenomenon whereby a genetic variant leads to an increase in fitness at one life-stage or in a specific environment, but simultaneously decreases fitness in another respect. Therefore, it is conceivable that the molecular underpinnings of evolution of highly complex traits, including brain size or cognitive ability, under certain conditions could result in deleterious effects, which would increase the susceptibility to psychiatric or neurodevelopmental diseases. Here, we discuss possible trade-offs and antagonistic pleiotropies between evolutionary change in a gene sequence, dosage or activity and the susceptibility of individuals to autism spectrum disorders and schizophrenia. We present current knowledge about genes and alterations in gene regulatory landscapes, which have likely played a role in establishing human-specific traits and have been implicated in those diseases.

No evidence for superior distractor filtering amongst individuals high in autistic-like traits

Autistic individuals and individuals with high levels of autistic-like traits often show better visual search performance than their neurotypical peers. The present work investigates whether this advantage stems from increased ability to filter out distractors. Participants with high or low levels of autistic-like traits completed an attentional blink task in which trials varied in target-distractor similarity. The results showed no evidence that high levels of autistic-like traits were associated with superior distractor filtering (indexed by the difference in the size of the attentional blink across the high- and low-similarity distractors). This suggests that search advantages seen in previous studies are likely linked to other mechanisms such as enhanced pre-attentive scene processing, better decision making, or more efficient response selection.

Differential neural correlates underlying mental rotation processes in two distinct cognitive profiles in autism

Enhanced visuospatial abilities characterize the cognitive profile of a subgroup of autistics. However, the neural correlates underlying such cognitive strengths are largely unknown. Using functional magnetic resonance imaging (fMRI), we investigated the neural underpinnings of superior visuospatial functioning in different autistic subgroups. Twenty-seven autistic adults, including 13 with a Wechsler's Block Design peak (AUTp) and 14 without (AUTnp), and 23 typically developed adults (TYP) performed a classic mental rotation task. As expected, AUTp participants were faster at the task compared to TYP. At the neural level, AUTp participants showed enhanced bilateral parietal and occipital activation, stronger occipito-parietal and fronto-occipital connectivity, and diminished fronto-parietal connectivity compared to TYP. On the other hand, AUTnp participants presented greater activation in right and anterior regions compared to AUTp. In addition, reduced connectivity between occipital and parietal regions was observed in AUTnp compared to AUTp and TYP participants. A greater reliance on posterior regions is typically reported in the autism literature. Our results suggest that this commonly reported finding may be specific to a subgroup of autistic individuals with enhanced visuospatial functioning. Moreover, this study demonstrated that increased occipito-frontal synchronization was associated with superior visuospatial abilities in autism. This finding contradicts the long-range under-connectivity hypothesis in autism. Finally, given the relationship between distinct cognitive profiles in autism and our observed differences in brain functioning, future studies should provide an adequate characterization of the autistic subgroups in their research. The main limitations are small sample sizes and the inclusion of male-only participants.

Figure-Disembedding Is Inferior in Non-autistic Compared to Autistic Individuals but Can Be Improved by Training

Background

Figure-disembedding is one of the most discussed visuo-cognitive functions, in which individuals with Autism Spectrum Disorder (ASD) have been reported to outperform non-autistic individuals. A local processing bias has been assumed to underlie such superior performance patterns. The aim of the current study is to investigate whether processing preferences can be modified by procedural priming.

Method

The current study used a procedural priming task (Navon figures) to induce more local or global processing in 25 autistic and 21 typically developing (TD) control participants, using hierarchical figures preceding the figure-disembedding task.

Results

Participants with ASD outperformed non-autistic individuals in the unprimed baseline task version. The performance was not modulated by priming in either direction (toward a local or global processing style) in both groups. However, the performance of TD control participants was improved by training to the same level as that observed in the ASD group.

Conclusion

Figure-disembedding performance in ASD is superior to that in TD control participants and robust against procedural priming or training. In contrast, performance in the TD control group can be improved up to the level of the ASD group. Any studies reporting superiority in individuals with ASD in figure-disembedding should consider training effects when evaluating group differences.

Characterizing Creative Thinking and Creative Achievements in Relation to Symptoms of Attention-Deficit/Hyperactivity Disorder and Autism Spectrum Disorder

Previous research on ADHD and ASD has mainly focused on the deficits associated with these conditions, but there is also evidence for strengths. Unfortunately, our understanding of potential strengths in neurodevelopmental conditions is limited. One particular strength, creativity, has been associated with both ADHD and ASD. However, the distinct presentations of both conditions beg the question whether ADHD and ASD associate with the same or different aspects of creativity. Therefore, the current study investigated the links between ADHD and ASD symptoms, creative thinking abilities, and creative achievements. To investigate the spectrum of ADHD and ASD symptoms, self-reported ADHD and ASD symptoms, convergent (Remote Associations Test) and divergent thinking (Alternative Uses Task) and creative achievements (Creative Achievement Questionnaire) were assessed in a self-reportedly healthy sample of adults (n = 470). We performed correlation analysis to investigate the relation between ADHD/ASD symptoms and creativity measures. In a second phase of analysis, data from an adult ADHD case-control study (n = 151) were added to investigate the association between ADHD symptoms and divergent thinking in individuals with and without a diagnosis of ADHD. Our analysis revealed that having more ADHD symptoms in the general population was associated with higher scores on all the outcome measures for divergent thinking (fluency, flexibility, and originality), but not for convergent thinking. Individuals with an ADHD diagnosis in the case-control sample also scored higher on measures of divergent thinking. Combining data of the population based and case-control studies showed that ADHD symptoms predict divergent thinking up to a certain level of symptoms. No significant associations were found between the total number of ASD symptoms and any of the creativity measures. However, explorative analyses showed interesting links between the ASD subdomains of problems with imagination and symptoms that relate to social difficulties. Our findings showed a link between ADHD symptoms and divergent thinking abilities that plateaus in the clinical spectrum of symptoms. For ASD symptoms, no relation was found with creativity measures. Increasing the knowledge about positive phenotypes associated with neurodevelopmental conditions and their symptom dimensions might aid psychoeducation, decrease stigmatization and improve quality of life of individuals living with such conditions.

Embedded figures in schizophrenia: A main deficit but no specificity

Visual deficits are core deficits of schizophrenia. Classically, deficits are determined with demanding psychophysical tasks requiring fine-grained spatial or temporal resolution. Less is known about holistic processing. Here, we employed the Leuven Embedded Figures Test (L-EFT) measuring classic aspects of Gestalt processing. A target shape is embedded in a context and observers have to detect as quickly as possible in which display the target is embedded. Targets vary in closure, symmetry, complexity, and good continuation. In all conditions, schizophrenia patients had longer RTs compared to controls and depressive patients and to a lesser extent compared to their siblings. There was no interaction suggesting that, once the main deficit of schizophrenia patients is discarded, there are no further deficits in Gestalt perception between the groups. This result is in line with a growing line of research showing that when schizophrenia patients are given sufficient time to accomplish the task, they perform as well as controls.

Annual Research Review: Shifting from 'normal science' to neurodiversity in autism science

Since its initial description, the concept of autism has been firmly rooted within the conventional medical paradigm of child psychiatry. Increasingly, there have been calls from the autistic community and, more recently, nonautistic researchers, to rethink the way in which autism science is framed and conducted. Neurodiversity, where autism is seen as one form of variation within a diversity of minds, has been proposed as a potential alternative paradigm. In this review, we concentrate on three major challenges to the conventional medical paradigm - an overfocus on deficits, an emphasis on the individual as opposed to their broader context and a narrowness of perspective - each of which necessarily constrains what we can know about autism and how we are able to know it. We then outline the ways in which fundamental elements of the neurodiversity paradigm can potentially help researchers respond to the medical model's limitations. We conclude by considering the implications of a shift towards the neurodiversity paradigm for autism science.

The effect of autistic traits on disembedding and mental rotation in neurotypical women and men

Recent data has revealed dissociations between social and non-social skills in both autistic and neurotypical populations. In the present study, we investigated whether specific visuospatial abilities, such as figure disembedding and mental rotation, are differently related to social and non-social autistic traits, in neurotypical women and men. University students (N = 426) completed the Autism Spectrum Quotient (AQ), figure disembedding and mental rotation of two-dimensional figures tasks. AQ social skills (AQ-social) and attention-to-details (AQ-attention) subscales were used as measures of social and non-social autistic traits, respectively. Mental rotation was affected by a significant interaction between sex, social and non-social traits. When non-social traits were above the mean (+ 1 SD), no sex differences in mental rotation were found. Instead, below this value, sex differences depended on the social traits, with men on average outperforming women at middle-to-high social traits, and with a comparable performance, and with women on average outperforming men, at lower social traits. A small positive correlation between figure disembedding and social traits was observed in the overall sample. These results are interpreted in terms of the hyper-systemizing theory of autism and contribute to the evidence of individual differences in the cognitive style of autistic people and neurotypical people with autistic traits.

Face-to-face learning enhances the social transmission of information

Learning from others provides the foundation for culture and the advancement of knowledge. Learning a new visuospatial skill from others represents a specific challenge-overcoming differences in perspective so that we understand what someone is doing and why they are doing it. The "what" of visuospatial learning is thought to be easiest from a shared 0° first-person perspective and most difficult from a 180° third-person perspective. However, the visual disparity at 180° promotes face-to-face interaction, which may enhance learning by scaffolding social perspective taking, the "why" of visuospatial learning. We tested these potentially conflicting hypotheses in child and young adult learners. Thirty-six children (4-6 years) and 57 young adults (18-27 years) observed a live model open a puzzle box from a first-person (0°) or third-person (90° or 180°) perspective. The puzzle box had multiple solutions, only one of which was modelled, which allowed for the assessment of imitation and goal emulation. Participants had three attempts to open the puzzle box from the model's perspective. While first-person (0°) observation increased imitation relative to a 180° third-person perspective, the 180° observers opened the puzzle box most readily (i.e., fastest). Although both age groups were excellent imitators and able to take the model's perspective, adults were more faithful imitators, and children were more likely to innovate a new solution. A shared visual perspective increased imitation, but a shared mental perspective promoted goal achievement and the social transmission of innovation. "Perfection of means and confusion of goals-in my opinion-seem to characterize our age" Einstein (1973) pg 337, Ideas and Opinions.

Exploratory study on the use of HMD virtual reality to investigate individual differences in visual processing styles

Purpose

Global and local processing is part of human perceptual organisation, where global processing helps extract the “gist” of the visual information and local processing helps perceive the details. Individual differences in these two types of visual processing have been found in autism and ADHD (Attention-Deficit Hyperactivity Disorder). Virtual reality (VR) has become a more available method of research in the last few decades. No previous research has investigated perceptual differences using this technology.

Design/methodology/approach

The objective of the research is to threefold: (1) identify if there is association between ADHD and autistic traits and the performance on the Rey-Osterrieth complex figure (ROCF) task, (2) investigate practical effects of using VR drawing tools for research on perceptual experiences and (3) explore any perceptual differences brought out by the three-dimensional nature of the VR. The standard ROCF test was used as a baseline task to investigate the practical utility of using VR as an experimental platform. A total of 94 participants were tested.

Findings

Attention-to-detail, attention switching and imagination subscales of autism quotient (AQ) questionnaire were found to be predictors of organisational ROCF scores, whereas only the attention-to-detail subscale was predictive of perceptual ROCF scores.

Originality/value

The current study is an example of how classic psychological paradigms can be transferred into the virtual world. Further investigation of the distinct individual preferences in drawing tasks in VR could lead to a better understanding of individual differences in the processing of visuospatial information.

Bilingualism effects on cognition in autistic children are not all-or-nothing: The role of socioeconomic status in intellectual skills in bilingual autistic children

LAY ABSTRACT

Previous research has suggested that bilingualism may improve cognition in children with autism, and that this boost may stem from improvement in executive functions. The Wechsler Intelligence Scales for Children are considered to be reliable and valid measures of intelligence when administered to autistic children. These measures have so far revealed unusual psychometric properties in monolingual autistic children, notably distinctive patterns of strengths and weaknesses and low inter-correlation among verbal and nonverbal IQ subtests. The way bilingualism affects the intellectual functioning of autistic children has not been explored yet. Nor has there been a satisfactory factor structure that explains monolingual and bilingual autistic children's IQ performance in terms of individual factors, such as age and socioeconomic status. The current study examined the intelligence profiles of 316 bilingual and age- and gender-matched monolingual children with autism using the Wechsler Intelligence Scales for Children-Third Edition. The study applied clustering models to extract intelligence subtypes of autism, and mediation analyses to examine potential mediation effects of age and socioeconomic status on the children's verbal and nonverbal IQ performance. The results support the mediational role of the children's socioeconomic status in the association between bilingualism and intelligence. Low-socioeconomic status bilingual autistic children outperformed their monolingual peers on both verbal and nonverbal subtests, while the differences faded in medium-socioeconomic status and high-socioeconomic status children. The findings emphasize the positive effects of bilingualism on low-socioeconomic status autistic children's intelligence and also highlight high-socioeconomic status as a factor that may mitigate discrepant patterns of strengths and weaknesses in monolingual children's IQ performance.

Are Executive Dysfunctions Relevant for the Autism-Specific Cognitive Profile?

Executive functions (EF) have been shown to be important for the understanding of Autism Spectrum Disorder (ASD), but dysfunctions of EF are not autism-specific. The specific role of EF in ASD, its relationship to core autism characteristics, such as mentalizing, needs to be explored. Medline- and PsychINFO databases were searched for studies published between 1990 and 2020 that included measures of EF in ASD and typically developing control persons (TD) in combination with either Theory of Mind (ToM) or Weak Central Coherence (WCC) tasks. A pre-registered meta-analysis and cross-study regression was performed including a total of 42 studies (ASD n = 1,546, TD n = 1,206). Results were reported according to PRISMA guidelines. In all cognitive domains, the ASD group showed significantly reduced performance. Importantly, EF subdomains and ToM were not significantly correlated. This finding rules out a significant association between EF subdomains and ToM and questions the relevance of EF dysfunctions for the autism-specific feature of reduced mentalizing.

Autism Spectrum Disorder and IQ - A Complex Interplay

Autism spectrum disorder (ASD) is characterized as a very heterogeneous child-onset disorder, whose heterogeneity is partly determined by differences in intelligence quotient (IQ). Older epidemiological studies suggested that the IQ-related spectrum tends to be skewed to the left, i.e., a larger proportion of individuals with ASD have below average intelligence, while only few individuals with ASD may have an IQ above average. This picture changed over time with broadening the spectrum view. Within the present perspective article, we discuss discrepancies in IQ profiles between epidemiological and clinical studies and identify potential underlying aspects, for example, the influence of external factors such as sample biases or differences in availability of autism health services. Additionally, we discuss the validity and reciprocal influences of ASD diagnostics and IQ measurement. We put the impact of these factors for diagnostic as well as care and support situations of patients into perspective and want to encourage further research to contribute to the conceptualization of "autism" more comprehensively including the IQ as well as to examine broader (life) circumstances, interacting factors and diagnostic requirements of given diagnoses in childhood as compared to adulthood.

Atypically slow processing of faces and non-faces in older autistic adults

Face recognition is a fundamental function that requires holistic processing. Differences in face processing have been consistently identified in autistic children, but it is unknown whether these differences persist across the adult lifespan. Using event-related functional magnetic resonance imaging, we measured holistic face processing with a rapid Mooney faces task in 50 autistic and 49 non-autistic participants (30–74 years). Behavioral tasks included a self-paced version of the same paradigm and a global–local processing task (Navon). Reduced detection rates for faces, but not non-faces, were found in autistic adults, including slower responses on all conditions. Without time constraints, differences in accuracy disappeared between groups, although reaction times in correctly identifying faces remained higher in autistic adults. The functional magnetic resonance imaging results showed lower activation in the left and right superior frontal gyrus in the autism group but no age-related differences. Overall, our findings point toward slower information processing speed rather than a face recognition deficit in autistic adults. This suggests that face-processing differences are not a core feature of autism across the adult lifespan.

Bilingualism Effects on the Cognitive Flexibility of Autistic Children: Evidence From Verbal Dual-Task Paradigms

The deficit in cognitive flexibility (i.e., the ability to adapt cognitive behavior to changing contexts) is one of the most prominent characteristics of autistic individuals. Inflexibility may manifest in restricted interests and increased susceptibility to the effects of misinformation either through inefficient inhibition of non-target information or deficient recall of correct information. Bilingualism has been shown to enhance executive functions in both typically developing children and autistic children; yet, the effect of bilingualism on cognitive flexibility in autism remains underexplored. In this study, we used verbal dual-tasks to compare cognitive flexibility across 50 monolingual autistic and 50 bilingual autistic children, and 50 monolingual and 50 bilingual typically developing children. The children were also administered language ability tests and a nonverbal global-local cognitive flexibility task, in order to investigate whether performance in the dual-tasks would be modulated by the children's language and executive function skills. The bilingual autistic children outperformed their monolingual autistic peers in the dual-tasks. The strength of the bilingualism effect, however, was modulated by the type of language processing that interfered with the target information in each dual-task, which suggests that the bilingual autistic children calibrated their processing resources and efficiently adapted them to the changing demands of the dual-task only to the extent that the task did not exceed their language abilities. Bilingual autistic children relied on their executive functions rather than on their language abilities while performing in the dual-tasks. The overall results show that bilingualism compensates for the reduced cognitive flexibility in autism.

Perceptual processing links autism and synesthesia: A co-twin control study

Synesthesia occurs more commonly in individuals fulfilling criteria for an autism spectrum diagnosis than in the general population. It is associated with autistic traits and autism-related perceptual processing characteristics, including a more detail-focused attentional style and altered sensory sensitivity. In addition, these characteristics correlate with the degree of grapheme-color synesthesia (consistency of grapheme-color associations) in non-synesthetes. We investigated a predominantly non-synesthetic twin sample, including individuals fulfilling criteria for an autism spectrum diagnosis or other neurodevelopmental disorders (n = 65, 14-34 years, 60% female). We modelled linear relationships between the degree of grapheme-color synesthesia and autistic traits, sensory sensitivity, and visual perception, both within-twin pairs (22 pairs) where all factors shared by twins are implicitly controlled (including 50-100% genetics), and across the entire cohort. We found that the degree of grapheme-color synesthesia was associated with autistic traits within the domain of Attention to Details and with sensory hyper-, but not hypo-sensitivity. These associations were stronger within-twin pairs than across the sample. Further, twins with a higher degree of grapheme-color synesthesia were better than their co-twins at identifying fragmented images (Fragmented Pictures Test). This is the first twin study on the association between synesthesia and autism-related perceptual features and traits. The results suggest that investigating these associations within-twin pairs, implicitly adjusting for potential confounding factors shared by twins, is more sensitive than doing so in non-related individuals. Consistent with previous findings, the results suggest an association between the degree of grapheme-color synesthesia and autism-related perceptual features, while utilizing a different measure for sensory sensitivity. The novel finding of enhanced fragmented picture integration in twins with a higher degree of grapheme-color synesthesia challenges the view of a generally more detail-focused attentional style in synesthesia and might be related to enhanced memory or mental imagery in more synesthetic individuals.

Predictive waves in the autism-schizophrenia continuum: A novel biobehavioral model

The brain is a predictive machine. Converging data suggests a diametric predictive strategy from autism spectrum disorders (ASD) to schizophrenic spectrum disorders (SSD). Whereas perceptual inference in ASD is rigidly shaped by incoming sensory information, the SSD population is prone to overestimate the precision of their priors' models. Growing evidence considers brain oscillations pivotal biomarkers to understand how top-down predictions integrate bottom-up input. Starting from the conceptualization of ASD and SSD as oscillopathies, we introduce an integrated perspective that ascribes the maladjustments of the predictive mechanism to dysregulation of neural synchronization. According to this proposal, disturbances in the oscillatory profile do not allow the appropriate trade-off between descending predictive signal, overweighted in SSD, and ascending prediction errors, overweighted in ASD. These opposing imbalances both result in an ill-adapted reaction to external challenges. This approach offers a neuro-computational model capable of linking predictive coding theories with electrophysiological findings, aiming to increase knowledge on the neuronal foundations of the two spectra features and stimulate hypothesis-driven rehabilitation/research perspectives.

The impact of visual-spatial abilities on theory of mind in children and adolescents with autism spectrum disorder

BACKGROUND

Children and adolescents with autism spectrum disorder (ASD) often experience impaired social cognition.

AIMS

In the present study, we aimed to investigate the relation between visual-spatial abilities and theory of mind in children and adolescents with and without ASD.

METHODS

Forty-five boys from the age of 7 to 17 years with ASD and thirty-one aged matched boys without ASD participated and completed the test of intrinsic stable visual-spatial ability (test of visual perceptual skill-revised), intrinsic dynamic visual-spatial ability (animal mental rotation test), and theory of mind test (TOMT).

RESULTS

Results showed that relative to boys without ASD, boys with ASD had a lower performance in theory of mind and intrinsic visual-spatial abilities. Secondly, theory of mind correlated with visual-spatial abilities in boys with ASD. Theory of mind for first and second order beliefs was predicted by the intrinsic dynamic visual abilities, whereas the theory of mind ability of emotion recognition was predicted by visual-spatial static abilities. In children without ASD, theory of mind for emotion recognition was predicted by intrinsic visual-spatial ability and the theory of mind for first order beliefs.

DISCUSSION

Theory of mind can be predicted by visual-spatial abilities in children and adolescents with ASD. Future studies should investigate the role of different types of intrinsic dynamic visual-spatial abilities (e.g., egocentric vs. object-based mental rotation tasks) in relation to different aspects of theory of mind in children and adolescents with autism.

Wechsler Intelligence Scale for Children, Fifth Edition Profiles of Children With Autism Spectrum Disorder Using a Classification and Regression Trees Analysis

The Wechsler Intelligence Scales for Children (WISC) are the most widely used instrument in assessing cognitive ability, especially with children with autism spectrum disorder (ASD). Previous literature on the WISC has demonstrated a divergent pattern of performance on the WISC for children ASD compared to their typically developing peers; however, there is a lack of research concerning the most recent iteration, the Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V). Due to the distinctive changes made to the WISC-V, we sought to identify the pattern of performance of children with ASD on the WISC-V using a classification and regression (CART) analysis. The current study used the standardization sample data of the WISC-V obtained from NCS Pearson, Inc. Sixty-two children diagnosed with ASD, along with their demographically matched controls, comprised the sample. Results revealed the Comprehension and Letter-Number Sequencing subtests were the most important factors in predicting group membership for children with ASD with an accompanying language impairment. Children with ASD without an accompanying language impairment, however, were difficult to distinguish from matched controls through the CART analysis. Results suggest school psychologists and other clinicians should administer all primary and supplemental subtests of the WISC-V as part of a comprehensive assessment of ASD.

Visual Sensory Experiences From the Viewpoint of Autistic Adults

Although previous research has investigated altered sensory reactivity in autistic individuals, there has been no specific focus on visual sensory experiences, particularly in adults. Using qualitative methods, this study aimed to characterize autistic visual sensory symptoms, contextualize their impact and document any associated coping strategies. A total of 18 autistic adults took part in four focus groups which involved questions around visual experiences, the impact of these on daily life, and strategies for their reduction. Transcripts of each session were thematically analyzed allocating six key themes. Participants described a range of visual hypersensitivities, including to light, motion, patterns and particular colors, which contributed to distraction and were frequently part of a wider multisensory issue. Such experiences had significant negative impacts on personal wellbeing and daily life with participants describing fatigue, stress and hindrances on day-to-day activities (e.g., travel and social activities). However, the degree of understanding that participants had about their visual experiences influenced their emotional response, with greater understanding reducing concern. Participants employed a variety of coping strategies to overcome visual sensory experiences but with varied success. Discussions also highlighted that there may be a poor public understanding of sensory issues in autism affecting how well autistic individuals are able manage their sensory symptoms. In summary, autistic adults expressed significant concern about their visual experiences and there is a need to improve understanding of visual experiences on a personal and public level as well as for developing potential support.

Genomic selection signatures in autism spectrum disorder identifies cognitive genomic tradeoff and its relevance in paradoxical phenotypes of deficits versus potentialities

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder characterized by paradoxical phenotypes of deficits as well as gain in brain function. To address this a genomic tradeoff hypothesis was tested and followed up with the biological interaction and evolutionary significance of positively selected ASD risk genes. SFARI database was used to retrieve the ASD risk genes while for population datasets 1000 genome data was used. Common risk SNPs were subjected to machine learning as well as independent tests for selection, followed by Bayesian analysis to identify the cumulative effect of selection on risk SNPs. Functional implication of these positively selected risk SNPs was assessed and subjected to ontology analysis, pertaining to their interaction and enrichment of biological and cellular functions. This was followed by comparative analysis with the ancient genomes to identify their evolutionary patterns. Our results identified significant positive selection signals in 18 ASD risk SNPs. Functional and ontology analysis indicate the role of biological and cellular processes associated with various brain functions. The core of the biological interaction network constitutes genes for cognition and learning while genes in the periphery of the network had direct or indirect impact on brain function. Ancient genome analysis identified de novo and conserved evolutionary selection clusters. The de-novo evolutionary cluster represented genes involved in cognitive function. Relative enrichment of the ASD risk SNPs from the respective evolutionary cluster or biological interaction networks may help in addressing the phenotypic diversity in ASD. This cognitive genomic tradeoff signatures impacting the biological networks can explain the paradoxical phenotypes in ASD.

Clinical and Translational Implications of an Emerging Developmental Substructure for Autism

A vast share of the population-attributable risk for autism relates to inherited polygenic risk. A growing number of studies in the past five years have indicated that inherited susceptibility may operate through a finite number of early developmental liabilities that, in various permutations and combinations, jointly predict familial recurrence of the convergent syndrome of social communication disability that defines the condition. Here, we synthesize this body of research to derive evidence for a novel developmental substructure for autism, which has profound implications for ongoing discovery efforts to elucidate its neurobiological causes, and to inform future clinical and biomarker studies, early interventions, and personalized approaches to therapy.

Heterogeneity of Research Results: A New Perspective From Which to Assess and Promote Progress in Psychological Science

Heterogeneity emerges when multiple close or conceptual replications on the same subject produce results that vary more than expected from the sampling error. Here we argue that unexplained heterogeneity reflects a lack of coherence between the concepts applied and data observed and therefore a lack of understanding of the subject matter. Typical levels of heterogeneity thus offer a useful but neglected perspective on the levels of understanding achieved in psychological science. Focusing on continuous outcome variables, we surveyed heterogeneity in 150 meta-analyses from cognitive, organizational, and social psychology and 57 multiple close replications. Heterogeneity proved to be very high in meta-analyses, with powerful moderators being conspicuously absent. Population effects in the average meta-analysis vary from small to very large for reasons that are typically not understood. In contrast, heterogeneity was moderate in close replications. A newly identified relationship between heterogeneity and effect size allowed us to make predictions about expected heterogeneity levels. We discuss important implications for the formulation and evaluation of theories in psychology. On the basis of insights from the history and philosophy of science, we argue that the reduction of heterogeneity is important for progress in psychology and its practical applications, and we suggest changes to our collective research practice toward this end.

A Developmental Profile of Children With Autism Spectrum Disorder in China Using the Griffiths Mental Development Scales

The purpose of this study was to profile the mental development of children aged 18 to 96 months with autism spectrum disorder (ASD) using the Chinese version of the Griffiths Mental Development Scales (GMDS), and to explore the relationships between developmental levels and ASD severity, the sex of the child and the age of ASD diagnosis. Children with ASD (n = 398; 337 boys, 61 girls) were recruited and ASD severity evaluated using the Autism Behavior Checklist and the Childhood Autism Rating Scale, while the GMDS was used to evaluate the children's mental development. Study participants were divided into groups according to GMDS general and subscale quotients, ASD severity, sex, and age. The majority of groups divided according to the GMDS quotients exhibited an unbalanced distribution in respect of the six domains of the GMDS and there were significant differences within the six subscale quotients. Autism severity, sex and age had significant effects on the overall level of development of autistic children. The quotients recorded for the children with more severe ASD were significantly lower than those for the children with less severe ASD. A markedly higher proportion of developmental delay was recorded for girls than boys in relation to the performance subscale. The locomotor quotient decreased in line with age at diagnosis, while autism severity and age had significant effects on the general and subscale quotients and sex had a significant effect on performance quotient. Children with ASD exhibit an uneven cognitive development profile, and their overall developmental levels are affected by autism severity, sex and age. Specific cognitive domains differ according to sex in children with ASD. Locomotor skills tend to decrease according to the age at diagnosis for autistic children aged 18 to 84 months. Autism severity and age are also associated with the level of functioning in different cognitive areas. These findings contribute to define the cognitive developmental profiles of children with ASD.

Interests and Strengths in Autism, Useful but Misunderstood: A Pragmatic Case-Study

Background

Studies on autistic strengths are often focused on what they reveal about autistic intelligence and, in some cases, exceptional and atypical reasoning abilities. An emerging research trend has demonstrated how interests and strengths often evident in autism can be harnessed in interventions to promote the well-being, adaptive, academic and professional success of autistic people. However, abilities in certain domains may be accompanied by major limitations in others, as well as psychiatric and behavioral issues, which may challenge their inclusion in support programs.

Objectives

To provide an in-depth, pragmatic, real-life example of the psychological and psychiatric management of interests and strengths in an autistic adolescent.

Method

An autistic teenager, C.A., with above-average calendar calculation and musical abilities, received psychiatric, neuropsychological, and language standardized and clinical assessments, combined with a measurement of his musical and calendar calculation abilities. C.A. and his parents then received psychiatric and psychological support over a 14-month period, targeting their perceptions of C.A.'s interests, strengths, and co-occurring difficulties.

Results

C.A. had a verbal IQ within the intellectual disability range and a non-verbal IQ in the low mean range. Modest calendar calculation, absolute pitch, and matrix abilities coexisted with severe receptive and expressive language disorder. The discrepancy between his abilities in areas of strengths and his limitations in other domains led to anxiety, frustration, and sometimes behavioral issues. Displacing the focus from academic performance to interests, as well as promoting the use of his strengths to develop new skills independently of their short-term adaptive benefits yielded positive effects on C.A.'s self-assessment, quality of life, and behavior at follow up.

Discussion

The appealing idea that abilities mostly found in autistic people, such as calendar calculation, can be directly harnessed into academic achievement and lead to paid employment may have detrimental effects, especially when such abilities are modest and associated with other limitations. These abilities should be primarily used to maximize well-being and quality of life, independently of their short-term adaptive function, which may or may not be positive.

Collinear facilitation and contour integration in autistic adults: Examining lateral and feedback connectivity

Alongside difficulties with communication and social interaction, autism is often accompanied by unusual sensory and perceptual experiences including enhanced visual performance on tasks that involve separating local parts from global context. This superiority may be the result of atypical integrative processing, involving feedback and lateral connections between visual neurons. The current study investigated the integrity of these connections in autistic adults by examining two psychophysics tasks that rely on these processes - collinear facilitation and contour integration. The relative contribution of feedback and lateral connectivity was studied by altering the timing of the target relative to the flankers in the collinear facilitation task, in 16 autistic and 16 non-autistic adults. There were no significant differences in facilitation between the autistic and non-autistic groups, indicating that for this task and participant sample, lateral and feedback connectivity appear relatively intact in autistic individuals. Contour integration was examined in a different group of 20 autistic and 18 non-autistic individuals, for open and closed contours to assess the closure effect (improved detection of closed compared to open contours). Autistic individuals showed a reduced closure effect at both short (150 ms) and longer (500 ms) stimulus presentation durations that was driven by better performance of the autistic group for the open contours. These results suggest that reduced closure in a simple contour detection paradigm is unlikely to be due to slower global processing. Reduced closure has implications for understanding sensory overload by contributing to reduced figure-ground segregation of salient visual features.

Executive functioning and spatial processing in anorexia nervosa: an experimental study and its significance for the allocentric lock theory

PURPOSE

The allocentric lock theory (ALT) suggests that people with eating disorders have difficulties in multisensory integration in two reference frames-egocentric and allocentric, whereby the egocentric, but not allocentric, is impaired. This leads to a distorted body image that contributes to the development and maintenance of the disorder. The current study aimed to explore a facet of the ALT, namely, the visuo-spatial aspect, and its relation to cognitive flexibility in patients with anorexia nervosa (AN).

METHODS

Fifty-five participants took part in the study: 20 AN patients and 35 controls, matched by age and education. The object perspective taking test (OPTT) and the mental rotation test (MRT), tapping egocentric and allocentric representations, respectively, and a set-shifting task were administered. The brief symptom inventory was used to measure overall levels of distress.

RESULTS

AN patients showed higher level of distress. They performed poorer on the OPTT and set-shifting task but not on the MRT. The OPTT and MRT were correlated for controls but not for AN patients, while the set-shifting task and body mass index were associated with the OPTT but not with the MRT for the AN patients.

CONCLUSIONS

The findings support the ALT by demonstrating impaired visual egocentric representations and intact allocentric visual functions in AN patients, with cognitive flexibility associated only with the egocentric frame. Therefore, egocentric frame impairment in AN patients may be influenced by visual perception and cognitive flexibility deficiency.

LEVEL OF EVIDENCE

Level III: case-control analytic study.

Hierarchical Processing in ASD is Driven by Exaggerated Salience Effects, not Local Bias

The role of relative salience in processing of hierarchical stimuli in individuals with autism spectrum disorder (ASD) was examined in this study. Participants with ASD and typically developing controls performed a Navon letters task under conditions of global salience, local salience or equal salience of both levels. Results revealed no group differences in level of processing (global or local) and no local bias for ASD. Rather, both groups showed better performance when targets were more salient compared to when distractors were more salient. Importantly, participants with ASD exhibited increased sensitivity to salience at the distractor level. We conclude that inconsistent findings in the context of global/local processing in ASD may stem from such exaggerated salience effects.

Global and local visual processing in autism - a co-twin-control study

BACKGROUND

Autism Spectrum Disorder (ASD) is associated with altered global and local visual processing. However, the nature of these alterations remains controversial, with contradictory findings and notions ranging from a reduced drive to integrate information into a coherent 'gestalt' ("weak central coherence" = WCC) to an enhanced perceptual functioning (EPF) in local processing.

METHODS

This study assessed the association between autism and global/local visual processing, using a large sample of monozygotic (MZ) and dizygotic (DZ) twins (N = 290, 48% females, age = 8-31 years). The Fragmented Pictures Test (FPT) assessed global processing, whereas local processing was estimated with the Embedded Figures Test (EFT) and the Block Design Test (BDT). Autism was assessed both categorically (clinical diagnosis), and dimensionally (autistic traits). Associations between visual tasks and autism were estimated both across the cohort and within-twin pairs where all factors shared between twins are implicitly controlled.

RESULTS

Clinical diagnosis and autistic traits predicted a need for more visual information for gestalt processing in the FPT across the cohort. For clinical diagnosis, this association remained within-pairs and at trend-level even within MZ twin pairs alone. ASD and higher autistic traits predicted lower EFT and BDT performance across the cohort, but these associations were lost within-pairs.

CONCLUSIONS

In line with the WCC account, our findings indicate an association between autism and reduced global visual processing in children, adolescents and young adults (but no evidence for EPF). Observing a similar association within MZ twins suggests a non-shared environmental contribution.

The Relation Between Autistic Traits, the Degree of Synaesthesia, and Local/Global Visual Perception

Synaesthesia is highly prevalent in autism spectrum disorder. We assessed the relation between the degree of autistic traits (Autism Spectrum Quotient, AQ) and the degree of synaesthesia in a neurotypical population, and hypothesized both are related to a local bias in visual perception. A positive correlation between total AQ scores and the degree of synaesthesia was found, extending previous studies in clinical populations. Consistent with our hypothesis, AQ-attention to detail scores were related to increased performance on an Embedded Figures Task and reduced susceptibility to visual illusions. We found no relation between autistic traits and performance on a motion coherence task, and no relation between synaesthesia and local visual perception. Possibly, this relation is reserved for supra-threshold synaesthetes.

Reduced nonverbal interpersonal synchrony in autism spectrum disorder independent of partner diagnosis: a motion energy study

BACKGROUND

One of the main diagnostic features of individuals with autism spectrum disorders is nonverbal behaviour difficulties during naturalistic social interactions. The 'Interactional Heterogeneity Hypothesis' of ASD proposes that the degree to which individuals share a common ground substantially influences their ability to achieve smooth social interactions.

METHODS

To test this hypothesis, we filmed 29 autistic and 29 matched typically developed adults engaged in several conversational tasks. Windowed cross-lagged correlations were computed using the time series of motion energy of both individuals in a dyad. These coefficients were then compared across the three dyad types that were homo- or heterogenous with respect to diagnosis: pairs of two autistic individuals, two typically developed individuals or pairs of one autistic and one typically developed person.

RESULTS

We found that all dyad types achieved above-chance interpersonal synchrony, but that synchrony was more expressed in typical dyads compared to both autistic and mixed dyads.

LIMITATIONS

The method presented here provides only one, albeit objective and robust, approach to explore synchrony. The methodological choices as well as the lack of consideration for other communication modalities may limit our interpretation of the findings. Moreover, the sample size is small with respect to exploring associations between synchrony and various outcome and social skill measures.

CONCLUSIONS

The present results do not provide support for the Interactional Heterogeneity Hypothesis given that autistic individuals do not coordinate better when interacting with another autistic individual, compared to when interacting with a typical individual.

Comparison of the K-WISC-IV profiles of boys with autism spectrum disorder and attention-deficit/hyperactivity disorder

AIMS

This study aimed to compare the intelligence profiles of children with autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) using the Korean Wechsler Intelligence Scale for Children-Fourth Edition (K-WISC-IV) scores to differentiate between their cognitive characteristics.

METHODS

Subjects were boys with ASD (n = 49) and ADHD (n = 44). The index and subtest scores of the ASD and ADHD groups were compared using MANOVA. Repeated-measures ANOVA was performed to investigate the cognitive strengths and weaknesses within the ASD and ADHD groups.

RESULTS

Verbal comprehension was significantly lower in the ASD group compared to the ADHD group. The ASD group also scored lower than the ADHD group on Vocabulary, Comprehension, Picture Concepts, Picture Completion, and Symbol Search. The ADHD group scored lower than the ASD group on Digit Span. The ASD group displayed slower processing speed and social judgment, while the ADHD group exhibited poor working memory and graphomotor processing.

CONCLUSION

The WISC-IV profiles might help distinguishing between the cognitive characteristics of ASD and ADHD boys.

Sex-specific variation in facial masculinity/femininity associated with autistic traits in the general population

Reports linking prenatal testosterone exposure to autistic traits and to a masculinized face structure have motivated research investigating whether autism is associated with facial masculinization. This association has been reported with greater consistency for females than for males, in studies comparing groups with high and low levels of autistic traits. In the present study, we conducted two experiments to examine facial masculinity/femininity in 151 neurotypical adults selected for either low, mid-range, or high levels of autistic traits. In the first experiment, their three-dimensional facial photographs were subjectively rated by 41 raters for masculinity/femininity and were objectively analysed. In the second experiment, we generated 6-face composite images, which were rated by another 36 raters. Across both experiments, findings were consistent for ratings of photographs and composite images. For females, a linear relationship was observed where femininity ratings decreased as a function of higher levels of autistic traits. For males, we found a U-shaped function where males with mid-range levels of traits were rated lowest on masculinity. Objective facial analyses revealed that higher levels of autistic traits were associated with less feminine facial structures in females and less masculine structures in males. These results suggest sex-specific relationships between autistic traits and facial masculinity/femininity.

The effects of autistic traits and academic degree on visuospatial abilities

In the present study, we were interested to investigate how autistic traits (including systemizing and empathy) and academic degree influence individuals' visuospatial abilities. To this end, 352 university students completed the Autism Spectrum Quotient (AQ), the Empathy Quotient, the Systemizing Quotient (SQ) and visuospatial tests measuring figure disembedding and mental rotation of two-dimensional figures. Engineering-design students (architecture and engineering) were the most accurate in disembedding and mentally rotating figures, followed by students of physical sciences (computer science, chemistry, physics, etc.) and fact-based humanities (languages, classics, law); biological (psychology and neuroscience, etc.) and systems-based social scientists (economics and commerce) were the least accurate. Engineering-design students also showed higher SQ scores with respect to the other four academic degree subjects, with students of biological sciences showing lower SQ scores. Importantly, results from a path analysis revealed that SQ (but not AQ) exerted an indirect effect on figure disembedding and mental rotations through the influence of the academic degree. Thus, the present findings reveal shady differences in systemizing degree and visuospatial performance within systemizing-based degree subjects. Implications for education are discussed.

A Developmental Perspective of Global and Local Visual Perception in Autism Spectrum Disorder

Individuals with autism spectrum disorder (ASD) demonstrate superior performances on visuo-spatial tasks emphasizing local information processing; however, findings from studies involving hierarchical stimuli are inconsistent. Wide age ranges and group means complicate their interpretability. Children and adolescents with and without ASD completed a Navon task wherein they identified global and local stimuli composed of either consistent or inconsistent letters. Trajectories of reaction time in global and local conditions were similar within and between groups when consistent and inconsistent stimuli were considered together, but the effect of local-to-global interference was significantly higher in participants with than without ASD. Age was not a significant predictor of local-to-global interference, suggesting that this effect emerges in childhood and persists throughout adolescence in ASD.