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Autism spectrum disorder (ASD) is a neurodevelopmental condition with a highly heterogeneous adult phenotype that includes social and non-social behavioral characteristics. The link between the characteristics assignable to the different domains remains unresolved. One possibility is that social and non-social behaviors in autism are modulated by a common underlying deficit. However, here we report evidence supporting an alternative concept that is individual-centered rather than deficit-centered. Individuals are assumed to have a distinctive style in the strategies they adopt to perform social and non-social tasks with these styles presumably being structured differently between autistic individuals and typically-developed (TD) individuals. We tested this hypothesis for the execution of time-coordinated (synchronized) actions. Participants performed (i) a social task that required synchronized gaze and pointing actions to interact with another person, and (ii) a non-social task that required finger-tapping actions synchronized to periodic stimuli at different time-scales and sensory modalities. In both tasks, synchronization behavior differed between ASD and TD groups. However, a principal component analysis of individual behaviors across tasks revealed associations between social and non-social features for the TD persons but such cross-domain associations were strikingly absent for autistic individuals. The highly differentiated strategies between domains in ASD are inconsistent with a general synchronization deficit and instead highlight the individualized developmental heterogeneity in the acquisition of domain-specific behaviors. We propose a cognitive model to help disentangle individual-centered from deficit-centered effects in other domains. Our findings reinforce the importance to identify individually differentiated phenotypes to personalize autism therapies., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background: Autism refers to a neurodevelopmental condition with characteristic impairments in social interaction and communication, restrictive and repetitive behaviors, as well as difficulties in sensory information processing and daily living skills. Even though symptoms persist from early childhood throughout the lifespan and often require long-term support, there is a lack of mental health services that sufficiently meet the needs of autistic adults. Previous evidence suggested individual, professional and structural barriers to healthcare for autistic adults. Here, using a peer research approach, we sought to systematically investigate barriers and needs in mental healthcare of autistic adults in Germany at the three relevant levels (individual, professional, structural) and from three relevant perspectives (autistic adults, relatives and healthcare providers), in order to obtain specific recommendations for optimized healthcare., Methods: Maximum variation sampling was used to account for the complexity of the research field. Semi-structured, open-ended interviews were conducted with autistic adults (n = 15) and focus groups with relatives/partners (n = 12), and healthcare providers of several professions (n = 15). Data analysis was performed using the codebook approach of thematic analysis., Results: Poor mental healthcare of autistic adults in Germany was characterized by six central and overarching themes: (i) lack of knowledge about autism, (ii) a need for increased participation/involvement, (iii) consideration of autism-specific needs in treatment, (iv) lack of services, (v) limited access to services, and (vi) improvement of stakeholder collaboration. Themes were similarly reported across participants, emphasizing dissatisfaction in all stakeholders., Conclusions: We identified major barriers to mental healthcare for autistic adults in Germany that affect autistic adults, but are also of concern to relatives and healthcare providers. Our results point to specific and generic areas for improvement, independent of stakeholder perspectives, which could guide future development of needs- and evidence-based services, recommendations and guidelines of mental healthcare for people with autism across the lifespan., Trial Registration: This study protocol was preregistered at the Open Science Framework ( https://osf.io/5x8pg )., (© 2023. The Author(s).)

The challenge of sustainably integrating highly educated individuals with ASD without intellectual disabilities in the first labor market is repeatedly described in literature. In a retrospective study, a group of 197 clinically late-diagnosed adults with ASD without intellectual disabilities was compared to a closely matched group of 501 individuals who did not meet the criteria for the diagnosis of ASD within a utilization population of the Cologne Autism Outpatient Clinic. Results indicated that the pronounced demand for reduction of social and interpersonal requirements at the workplace (including planned or limited contact with colleagues and customers) as well as the experience of difficulties following unexpected changes in the daily routine were specific for ASD. In addition, individuals with ASD reported greater difficulties in finding a suitable job and being able to live on their wages, taking age and educational qualification into account. Supported employment measures were provided significantly more frequently to individuals in the ASD group. In conclusion, impairments in social skills emerged as one of the main obstacles of workplace performance for individuals with ASD emphasizing the necessity to develop and apply ASD-specific support services., (© 2023 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC.)

The organisation of who speaks when in conversation is perhaps the most fundamental aspect of human communication. Research on a wide variety of groups of speakers has revealed a seemingly universal preference for between-speaker transitions consisting of very short silent gaps. Previous research on conversational turn-taking in Autism Spectrum Disorder (ASD) consists of only a handful of studies, most of which are limited in scope and based on the non-spontaneous speech of children and adolescents. No previous studies have investigated dialogues between autistic adults. We analysed the conversational turn-taking behaviour of 28 adult native German speakers in two groups of dyads, in which both interlocutors either did or did not have a diagnosis of ASD. We found no clear difference in turn-timing between the ASD and the control group overall, with both groups showing the same preference for very short silent-gap transitions that has been described for many other groups of speakers in the past. We did, however, find a clear difference between groups specifically in the earliest stages of dialogue, where ASD dyads produced considerably longer silent gaps than controls. We discuss our findings in the context of the previous literature, the implications of diverging behaviour specifically in the early stages of conversation, and the general importance of studying the neglected aspect of interactions between autistic adults., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Wehrle et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Introduction: Autism refers to an early-onset neurodevelopmental condition with characteristic impairments and difficulties in practical living skills, which persist across the lifespan such that adults with autism often require substantial support and comprehensive care. Yet, mental health and other services are frequently unavailable for adults with autism despite considerable need for mental healthcare and individual, familial and socioeconomic burdens. This study will (1) examine current needs, barriers and burdens related to ineffective healthcare of adults with autism in Germany, (2) develop specific recommendations for a need-oriented mental healthcare model and (3) evaluate its future implementation., Methods and Analysis: A mixed-methods design with three phases will be conducted. In phase 1, current mental healthcare for adults with autism will be assessed at three levels (individual, structural and professional) and from three perspectives (adults with autism, relatives and healthcare providers) using (1) focus groups/interviews (qualitative data) and (2) large-scale online surveys (quantitative data). Furthermore, service utilisation and related costs will be estimated. In phase 2, recommendations for a future healthcare model will be derived based on phase 1, considering the heterogeneous and complex needs within the autism spectrum and specifying indications for recommended services. In phase 3, these will again be evaluated by the three stakeholder groups using mixed-methods and analysed regarding feasibility of implementation and cost-effectiveness. Our study will, thus, contribute to a better translation of recommendations into practice to reduce disability, burden and costs related to ineffective healthcare and improve mental health outcomes for adults with autism and those who support them., Ethics and Dissemination: This study was approved by the Local Psychological Ethics Commission of the Center for Psychosocial Medicine at the University Medical Center Hamburg-Eppendorf (LPEK-0227). Findings will be disseminated via scientific meetings and peer-reviewed journals. Cooperating partners and associations will be informed about the study's course and findings by regular newsletters and meetings., Trial Registration Number: This study protocol was preregistered at the Open Science Framework (osf.io/5x8pg)., Competing Interests: Competing interests: DS received honoraria for lectures from or has been an advisor to Janssen, ROVI, Lundbeck, Otsuka Pharma and Takeda. The remaining authors do not declare other competing interests., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Pronounced alexithymia traits have been found in autism spectrum disorder (ASD) and recent research has been carving out the impact alexithymia traits might have on mentalising deficits associated with ASD., Method: In this cross-sectional study, a large representative referral population for diagnostic examination for possible ASD (n = 400) was screened for clinical alexithymia with a German version of the Reading the Mind in the Eyes test (RME). In contrast to previous attempts to carve out the impact of alexithymia traits on mentalising deficits though, we employed dominance analysis to account for the correlation between predictors. The relative relationship between alexithymia traits and autism traits with RME performance was investigated in the group of individuals with confirmed ASD diagnosis (N = 281) and compared to the clinical referral sample in which ASD was ruled out (N = 119)., Results: Dominance analysis revealed autism traits to be the strongest predictor for reduced mentalising skills in the ASD sample, whereas alexithymia contributed significantly less. In the sample of individuals with ruled out diagnosis, autism traits were the strongest predictor, but alexithymia traits were in sum equally associated to mentalising, with the External-Oriented Thinking subscale as an important predictor of this association., Limitations: It needs to be considered that the cross-sectional study design does not allow for causal inference. Furthermore, mentalising is a highly facetted capacity and measurements need to reduce this complexity into simple quantities which limits the generalizability of results., Discussion: While alexithymia traits should be considered for their mental health importance, they do not dominate the explanation of reduced mentalising skills in individuals with ASD, but they might do to a larger degree in individuals with ruled out ASD., (© 2022. The Author(s).)

In this study we investigate whether persons with autism spectrum disorder (ASD) perceive social images differently than control participants (CON) in a graded perception task in which stimuli emerged from noise before dissipating into noise again. We presented either social stimuli (humans) or non-social stimuli (objects or animals). ASD were slower to recognize images during their emergence, but as fast as CON when indicating the dissipation of the image irrespective of its content. Social stimuli were recognized faster and remained discernable longer in both diagnostic groups. Thus, ASD participants show a largely intact preference for the processing of social images. An exploratory analysis of response subsets reveals subtle differences between groups that could be investigated in future studies., (© 2021. The Author(s).)

When contemplating the alarming depression rates in adults with autism spectrum disorder (ASD), there is a need to find factors explaining heightened symptoms of depression. Beyond the impact of autism traits, markedly increased levels of alexithymia traits should be considered as a candidate for explaining why individuals with ASD report higher levels of depressive symptoms. Here, we aim to identify the extent to which autism or alexithymia traits indicate depressive symptoms in ASD and whether the pattern of association are specific to ASD. Data of a large (N = 400) representative clinical population of adults referred to autism diagnostics have been investigated and split by cases with a confirmed ASD diagnosis (N = 281) and cases with a ruled out ASD diagnosis (N = 119). Dominance analysis revealed the alexithymia factor, difficulties in identifying feelings, as the strongest predictor for depressive symptomatology in ASD, outweighing autism traits and other alexithymia factors. This pattern of prediction was not specific to ASD and was shared by clinical controls from the referral population with a ruled out ASD diagnosis. Thus, the association of alexithymia traits with depression is not unique to ASD and may constitute a general psychopathological mechanism in clinical samples.

We simultaneously revisited the Autism Diagnostic Interview-Revised (ADI-R) and Autism Diagnostic Observation Schedule (ADOS) with a comprehensive data-analytics strategy. Here, the combination of pattern-analysis algorithms and extensive data resources (n = 266 patients aged 7-49 years) allowed identifying coherent clinical constellations in and across ADI-R and ADOS assessments widespread in clinical practice. Our clustering approach revealed low- and high-severity patient groups, as well as a group scoring high only in the ADI-R domains, providing quantitative contours for the widely assumed autism subtypes. Sparse regression approaches uncovered the most clinically predictive questionnaire domains. The social and communication domains of the ADI-R showed convincing performance to predict the patients' symptom severity. Finally, we explored the relative importance of each of the ADI-R and ADOS domains conditioning on age, sex, and fluid IQ in our sample. The collective results suggest that (i) identifying autism subtypes and severity for a given individual may be most manifested in the ADI-R social and communication domains, (ii) the ADI-R might be a more appropriate tool to accurately capture symptom severity, and (iii) the ADOS domains were more relevant than the ADI-R domains to capture sex differences.

Behavioral research has revealed deficits in the development of joint attention (JA) as one of the earliest signs of autism. While the neural basis of JA has been studied predominantly in adults, we recently demonstrated a protracted development of the brain networks supporting JA in typically developing children and adolescents. The present eye-tracking/fMRI study now extends these findings to adolescents with autism. Our results show that in adolescents with autism JA is subserved by abnormal activation patterns in brain areas related to social cognition abnormalities which are at the core of ASD including the STS and TPJ, despite behavioral maturation with no behavioral differences. Furthermore, in the autism group we observed increased neural activity in a network of social and emotional processing areas during interactions with their mother. Moreover, data indicated that less severely affected individuals with autism showed higher frontal activation associated with self-initiated interactions. Taken together, this study provides first-time data of JA in children/adolescents with autism incorporating the interactive character of JA, its reciprocity and motivational aspects. The observed functional differences in adolescents ASD suggest that persistent developmental differences in the neural processes underlying JA contribute to social interaction difficulties in ASD.

This study was conducted to examine interpersonal predictive coding in individuals with high-functioning autism (HFA). Healthy and HFA participants observed point-light displays of two agents (A and B) performing separate actions. In the 'communicative' condition, the action performed by agent B responded to a communicative gesture performed by agent A. In the 'individual' condition, agent A's communicative action was substituted by a non-communicative action. Using a simultaneous masking-detection task, we demonstrate that observing agent A's communicative gesture enhanced visual discrimination of agent B for healthy controls, but not for participants with HFA. These results were not explained by differences in attentional factors as measured via eye-tracking, or by differences in the recognition of the point-light actions employed. Our findings, therefore, suggest that individuals with HFA are impaired in the use of social information to predict others' actions and provide behavioural evidence that such deficits could be closely related to impairments of predictive coding., (© 2016 The Authors.)

The most consistent cognitive sex differences have been found in the visuo-spatial domain, using Mental Rotation (MR) tasks. Such sex differences have been suggested to bear implications on our understanding of autism spectrum disorders (ASD). However, it is still debated how the sex difference in MR performance relates to differences between individuals with ASD compared to typically developed control persons (TD). To provide a detailed exploration of sex differences in MR performance, we studied rotational (indicated by slopes) and non-rotational aspects (indicated by intercepts) of the MR task in TD individuals (total N = 50). Second-to-fourth digit length ratios (2D:4D) were measured to investigate the associations between prenatal testosterone and performance on MR tasks. Handedness was assessed by the use of the Edinburgh Handedness Inventory in order to examine the relation between handedness and MR performance. In addition, we investigated the relation of spatial to systemising abilities, both of which have been associated with sex differences and with ASD, employing the Intuitive Physics Test (IPT). Results showed a male advantage in rotational aspects of the MR task, which correlated with IPT results. These findings are in contrast to the MR performance of individuals with ASD who have been shown to outperform TD persons in the non-rotational aspects of the MR task. These results suggest that the differences in MR performance due to ASD are different from sex-related differences in TD persons, in other words, ASD is not a simple and continuous extension of the male cognitive profile into the psychopathological range as the extreme male brain hypothesis (EMB) of ASD would suggest.

Little is known about whether stereotypes influence social judgments of autistic individuals, in particular when they compete with tacit face-to-face cues. We compared impression formation of 17 subjects with high-functioning autism (HFA) and 17 age-, gender- and IQ-matched controls. Information about the profession of a job applicant served as stereotype activating information. The target person's nonverbal behavior was presented as a computer animation showing two virtual characters in interaction. Contrary to our hypothesis, HFA participants were as sensitive to nonverbal cues as controls. Moreover, HFA showed a tendency to evaluate persons more positively. This might indicate a routine HFA apply in impression formation in order to compensate for their deficit in intuitive understanding of nonverbal communication cues.

Observing eye contact between others enhances the tendency to subsequently follow their gaze and has been suggested to function as a social signal that adds meaning to an upcoming action or event. The present study investigated effects of observed eye contact in high-functioning autism (HFA). Two faces on a screen either looked at or away from each other before providing congruent or incongruent gaze cues to one of two target locations. In contrast to control participants, HFA participants did not depict enhanced gaze following after observing eye contact. Individuals with autism, hence, do not seem to process observed mutual gaze as a social signal indicating the relevance of upcoming (gaze) behaviour. This may be based on the reduced tendency of individuals with HFA to engage in social gaze behavior themselves, and might underlie some of the characteristic deficiencies in social communicative behaviour in autism.

The ability of perspective taking is a fundamental aspect of social cognition. The ability to decide, what another person can or cannot see is referred to as "level 1 perspective taking." This is thought to be a process that we can make use of intentionally, but which also takes place spontaneously. Autism is characterized by impairments of social interaction, which are thought to be related to deficits in implicit rather than explicit perspective taking. In order to assess both levels of processing with regard to perspective taking, we employed an established task in patients and controls. Our results demonstrate that both groups engage in spontaneous level 1 perspective taking. In contrast to controls, however, patients reacted more slowly if they had to verify the other's as compared to their own perspective, which shows that participants with high-functioning autism have selective difficulties in explicit, but not implicit, level 1 perspective taking. These findings demonstrate that while spontaneous level 1 perspective taking appears to be intact in autism, this ability is impaired in patients when used explicitly., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: High functioning autism is an autism spectrum disorder that is characterized by deficits in social interaction and communication as well as repetitive and restrictive behavior while intelligence and general cognitive functioning are preserved. According to the weak central coherence account, individuals with autism tend to process information detail-focused at the expense of global form. This processing bias might be reflected by deficits in sensorimotor gating, a mechanism that prevents overstimulation during the transformation of sensory input into motor action. Prepulse inhibition is an operational measure of sensorimotor gating, which indicates an extensive attenuation of the startle reflex that occurs when a startling pulse is preceded by a weaker stimulus, the prepulse., Methods: In the present study, prepulse inhibition of acoustic startle was compared between 17 adults with high functioning autism and 17 sex-, age-, and intelligence-matched controls by means of electromyography., Results: Results indicate that participants with high functioning autism exhibited significantly higher startle amplitudes than the control group. However, groups did not differ with regard to PPI or habituation of startle., Discussion: These findings challenge the results of two previous studies that reported prepulse inhibition deficits in high-functioning autism and suggest that sensorimotor gating is only impaired in certain subgroups with autism spectrum disorder.

When movements indicate meaningful actions, even nonbiological objects induce the impression of "having a mind" or animacy. This basic social ability was investigated in adults with high-functioning autism (HFA, n = 13, and matched controls, n = 13) by systematically varying motion properties of simple geometric shapes. Critically, trial-by-trial variations of (1) motion complexity of stimuli, and of (2) participants' individual animacy ratings were separately correlated with neural activity to dissociate cognitive strategies relying more closely on stimulus analysis vs. subjective experience. Increasing motion complexity did not yield any significant group differences, and in both groups, it correlated with neural activity in regions involved in perceptual and evaluative processing, including the ventral medial prefrontal cortex (mPFC), superior temporal gyrus (STG) and posterior cingulate cortex (PCC). In contrast, although there were no significant behavioral differences between the groups, increasing animacy ratings correlated with neural activity in the insula, STG, amygdala, dorsal mPFC and PCC more strongly in controls than in HFA. These results indicate that in HFA the evaluation of stimulus properties cuing for animacy is intact, while increasing subjective ratings do not seem to be robustly related to social processing, including spontaneous mental state inferences and experience of salience.

Human-human interactions are of central relevance for the success in professional and occupational environments, which also substantially influence quality of life. This is especially true in the case of individuals with high-functioning autism (HFA), who experience deficits in social cognition that often lead to social exclusion and unemployment. Despite good education and high motivation, individuals with HFA do not reach employment rates that are substantially higher than 50 %. This is an alarmingly high rate of unemployment considering that the United Nations have recently emphasized the inclusion of handicapped persons as a mandatory human right. To date, the specific needs of autistic persons with respect to their working environment are largely unexplored. It remains moreover an open question how support systems and activities, including newly developed communication devices for professional environments of individuals with HFA, should look like. The German health and social care systems are not adequately prepared for the proper support of this population. This leads us to suggest that supported employment programs should be developed for adults with HFA that specifically address their needs and requirements. Such programs should comprise (1) the adequate assessment of HFA, including a neuropsychological profile and an individual matching of persons' preferences with requirements of the working place, (2) on-the-job coaching activities that include systematic communication and interaction training, and (3) instruction of non-autistic peers, including colleagues and supervisors, about weaknesses and strengths of HFA.

We investigated the influence of control over a social stimulus on the ability to detect direct gaze in high-functioning autism (HFA). In a pilot study, 19 participants with and 19 without HFA were compared on a gaze detection and a gaze setting task. Participants with HFA were less accurate in detecting direct gaze in the detection task, but did not differ in their ability to establish direct gaze in the setting task. In the main experiment, the results of the pilot study were replicated with 37 participants with and 39 without HFA, suggesting that individuals with HFA have a specific deficit in the passive perception of social cues as opposed to the active control, which seems to be intact.

Perceiving someone else's gaze shift toward an object can influence how this object will be manipulated by the observer, suggesting a modulatory effect of a gaze-based social context on action control. High-functioning autism (HFA) is characterized by impairments of social interaction, which may be associated with an inability to automatically integrate socially relevant nonverbal cues when generating actions. To explore these hypotheses, we made use of a stimulus-response compatibility paradigm in which a comparison group and patients with HFA were asked to generate spatially congruent or incongruent motor responses to changes in a face, a face-like and an object stimulus. Results demonstrate that while in the comparison group being looked at by a virtual other leads to a reduction of reaction time costs associated with generating a spatially incongruent response, this effect is not present in the HFA group. We suggest that this modulatory effect of social gaze on action control might play an important role in direct social interactions by helping to coordinate one's actions with those of someone else. Future research should focus on these implicit mechanisms of interpersonal alignment ('online' social cognition), which might be at the very heart of the difficulties individuals with autism experience in everyday social encounters.

Individuals suffering from autism spectrum disorders (ASD) often show a tendency for detail- or feature-based perception (also referred to as "local processing bias") instead of more holistic stimulus processing typical for unaffected people. This local processing bias has been demonstrated for the visual and auditory domains and there is evidence that multisensory processing may also be affected in ASD. Most multisensory processing paradigms used social-communicative stimuli, such as human speech or faces, probing the processing of simultaneously occuring sensory signals. Multisensory processing, however, is not limited to simultaneous stimulation. In this study, we investigated whether multisensory processing deficits in ASD persist when semantically complex but nonsocial stimuli are presented in succession. Fifteen adult individuals with Asperger syndrome and 15 control persons participated in a visual-audio priming task, which required the classification of sounds that were either primed by semantically congruent or incongruent preceding pictures of objects. As expected, performance on congruent trials was faster and more accurate compared with incongruent trials (crossmodal priming effect). The Asperger group, however, did not differ significantly from the control group. Our results do not support a general multisensory processing deficit, which is universal to the entire autism spectrum., (Copyright © 2011, International Society for Autism Research, Wiley-Liss, Inc.)

Cortical thickness (CT) changes possibly contribute to the complex symptomatology of autism. The aberrant developmental trajectories underlying such differences in certain brain regions and their continuation in adulthood are a matter of intense debate. We studied 28 adults with high-functioning autism (HFA) and 28 control subjects matched for age, gender, IQ and handedness. A surface-based whole brain analysis utilizing FreeSurfer was employed to detect CT differences between the two diagnostic groups and to investigate the time course of age-related changes. Direct comparison with control subjects revealed thinner cortex in HFA in the posterior superior temporal sulcus (pSTS) of the left hemisphere. Considering the time course of CT development we found clusters around the pSTS and cuneus in the left and the paracentral lobule in the right hemisphere to be thinner in HFA with comparable age-related slopes in patients and controls. Conversely, we found clusters around the supramarginal gyrus and inferior parietal lobule (IPL) in the left and the precentral and postcentral gyrus in the right hemisphere to be thinner in HFA, but with different age-related slopes in patients and controls. In the latter regions CT showed a steady decrease in controls but no analogous thinning in HFA. CT analyses contribute in characterizing neuroanatomical correlates of HFA. Reduced CT is present in brain regions involved in social cognition. Furthermore, our results demonstrate that aberrant brain development leading to such differences is proceeding throughout adulthood. Discrepancies in prior morphometric studies may be induced by the complex time course of cortical changes., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Individuals with autism often show a fragmented way of perceiving their environment, suggesting a disorder of information integration, possibly due to disrupted communication between brain areas. We investigated thirteen individuals with high-functioning autism (HFA) and thirteen healthy controls using the metastable motion quartet, a stimulus consisting of two dots alternately presented at four locations of a hypothetical square, thereby inducing an apparent motion percept. This percept is vertical or horizontal, the latter requiring binding of motion signals across cerebral hemispheres. Decreasing the horizontal distance between dots could facilitate horizontal percepts. We found evidence for altered horizontal binding in HFA: Individuals with HFA needed stronger facilitation to experience horizontal motion. These data are interpreted in light of reduced cross-hemispheric communication.

The goal of the study was to investigate the size of the corpus callosum (CC) and its subsegments in relation to total brain volume (TBV) as an empirical indicator of impaired connectivity in autism with special respect to gender. In MRI data sets of 29 adults with high-functioning autism (HFA) and 29 age-, gender- and IQ-matched control subjects, the TBV was measured and the CC was analyzed as a whole and in subsegments employing two different manual segmentation procedures. With respect to diagnosis, there were no significant differences in the dependent variables (CC, CC subsegments, and TBV). With respect to gender, only TBV was significantly increased in males compared with females, resulting in a significantly decreased CC/TBV ratio in males. This finding, however, was independent from gender and can be fully attributed to brain size. Our findings do not support the following hypotheses: (1) a hypothesis of impaired CC in HFA adults as a subgroup of patients with autism spectrum disorders, and (2) the sexual dimorphism hypothesis of the CC., (Copyright 2010 Elsevier Ireland Ltd. All rights reserved.)

We investigated feelings of involvement evoked by nonverbal behaviour of dynamic virtual characters in 20 adults with high-functioning autism (HFA) and high IQ as well as 20 IQ-matched control subjects. The effects of diagnostic group showed that subjects with autism experienced less "contact" and "urge" to establish contact across conditions and less "interest" than controls in a condition with meaningful facial expressions. Moreover, the analyses within groups revealed that nonverbal behaviour had less influence on feelings in HFA subjects. In conclusion, disturbances of HFA subjects in experiencing involvement in social encounters with virtual characters displaying nonverbal behaviour do not extend to all kinds of feelings, suggesting different pathways in the ascription of involvement in social situations.

Deficits in social cognition and interaction, such as in mentalizing and imitation behavior, are hallmark features of autism spectrum disorders. Both imitation and mentalizing are at the core of the sense of agency, the awareness that we are the initiators of our own behavior. Little evidence exists regarding the sense of agency in autism. Thus, we compared high-functioning adults with autism to healthy control subjects using an action monitoring and attribution task. Subjects with autism did not show deficits in this task, yet they showed significant mentalizing deficits. Our findings indicate a dissociation between the sense of agency and ascription of mental states in autism. We propose that social-cognitive deficits in autism may arise on a higher level than that of action monitoring and awareness.