Search

Altered sensory perception has been found in patients with autism spectrum disorders (ASD) and might be related to aberrant sensory perception thresholds. We used the well-established, standardized Quantitative sensory testing (QST) protocol of the German Research Network on Neuropathic Pain to investigate 13 somatosensory parameters including thermal and tactile detection and pain thresholds in 13 ASD adults and 13 matched healthy controls with normal IQ values. There were no group differences between somatosensory detection and pain thresholds. Two ASD patients showed paradoxical heat sensations and another two ASD subjects presented dynamic mechanical allodynia; somatosensory features that were absent in controls. These findings suggest that central mechanisms during complex stimulus integration rather than peripheral dysfunctions probably determine somatosensory alterations in ASD. [ABSTRACT FROM AUTHOR]

Diagnosing Autism Spectrum Disorders (ASD) is important throughout the lifespan. The objective was to investigate the transcultural diagnostic validity of the Social Communication Questionnaire (SCQ) in a clinical sample of 451 adults with Intellectual Developmental Disorder (IDD) with and without ASD in Germany, the U.S.A. and Great Britain. Variables associated with higher SCQ sum-scores were higher levels of IDD, male gender, a diagnosis of ASD and the study site (Germany > U.S.A > G.B.). An ROC analysis revealed a cut-score of 13, which resulted in a sensitivity of 0.87 and a specificity of 0.58. It is recommended to adjust the cut-score according to level of IDD and gender. Further research is needed to align diagnostic assignment of ASD across different sites and countries. [ABSTRACT FROM AUTHOR]

To reduce phenotypic heterogeneity of Autism spectrum disorders (ASD) and add to the current diagnostic discussion this study aimed at identifying clinically meaningful ASD subgroups. Cluster analyses were used to describe empirically derived groups based on the Autism Diagnostic Interview-revised (ADI-R) in a large sample of n = 463 individuals with ASD aged 3-21. Three clusters were observed. Most severely affected individuals regarding all core symptoms were allocated to cluster 2. Cluster 3 comprised moderate symptom severity of social communication impairments (SCI) and less stereotyped repetitive behavior (RRB). Minor SCI and relatively more RRB characterized cluster 1. This study offers support for both, a symptom profile, and a gradient model of ASD within the spectrum due to the sample included. [ABSTRACT FROM AUTHOR]

Individuals with autism spectrum disorder (ASD) have been proposed to show greater impairments in implicit than explicit mentalizing. To test this proposition, we developed two comparable naturalistic tasks for a performance-based approximation of implicit and explicit mentalizing in 28 individuals with ASD and 23 matched typically developed (TD) participants. Although both tasks were sensitive to the social impairments of individuals with ASD, implicit mentalizing was not more dysfunctional than explicit mentalizing. In TD participants, performance on the tasks did not correlate with each other, whereas in individuals with ASD they were highly correlated. These findings suggest that implicit and explicit mentalizing processes are separable in typical development. In contrast, in individuals with ASD implicit and explicit mentalizing processes are similarly impaired and closely linked suggesting a lack of developmental specification of these processes in ASD. [ABSTRACT FROM AUTHOR]

Abnormal brain oscillatory activity has been found in autism spectrum disorders (ASD) and proposed as a potential biomarker. While several studies have investigated gamma oscillations in ASD, none have examined resting gamma power across multiple brain regions. This study investigated resting gamma power using EEG in 15 boys with ASD and 18 age and intelligence quotient matched typically developing controls. We found a decrease in resting gamma power at right lateral electrodes in ASD. We further explored associations between gamma and ASD severity as measured by the Social Responsiveness Scale (SRS) and found a negative correlation between SRS and gamma power. We believe that our findings give further support of gamma oscillations as a potential biomarker for ASD. [ABSTRACT FROM AUTHOR]

Individuals with an autism spectrum disorder (ASD) show hallmark deficits in social perception. These difficulties might also reflect fundamental deficits in integrating visual signals. We contrasted predictions of a social perception and a spatial-temporal integration deficit account. Participants with ASD and matched controls performed two tasks: the first required spatiotemporal integration of global motion signals without social meaning, the second required processing of socially relevant local motion. The ASD group only showed differences to controls in social motion evaluation. In addition, gray matter volume in the temporal-parietal junction correlated positively with accuracy in social motion perception in the ASD group. Our findings suggest that social-perceptual difficulties in ASD cannot be reduced to deficits in spatial-temporal integration. [ABSTRACT FROM AUTHOR]

This study broadly examines executive (EF) and visuo-motor function in 30 adolescent and adult individuals with high-functioning autism spectrum disorder (ASD) in comparison to 28 controls matched for age, gender, and IQ. ASD individuals showed impaired spatial working memory, whereas planning, cognitive flexibility, and inhibition were spared. Pure movement execution during visuo-motor information processing also was intact. In contrast, execution time of reading, naming, and of visuo-motor information processing tasks including a choice component was increased in the ASD group. Results of this study are in line with previous studies reporting only minimal EF difficulties in older individuals with ASD when assessed by computerized tasks. The finding of impaired visuo-motor information processing should be accounted for in further neuropsychological studies in ASD. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]