scholarly journals Disrupted neural adaptation in autism spectrum disorder

2018 ◽  
Author(s):  
Rachel Millin ◽  
Tamar Kolodny ◽  
Anastasia V. Flevaris ◽  
Alex M. Kale ◽  
Michael-Paul Schallmo ◽  
...  
Keyword(s):  
Autism Spectrum Disorder ◽  
Direct Evidence ◽  
Visual Stimulation ◽  
Reaction Times ◽  
Autism Spectrum ◽  
Neural Adaptation ◽  
Spectrum Disorder ◽  
Button Press ◽  
Cortical Areas ◽  
Neural Excitation

AbstractThere has been long-standing speculation that autism spectrum disorder (ASD) involves an increase in excitation relative to inhibition. However, there is little direct evidence of increased neural excitation in humans with ASD. Here we provide a potential explanation for this discrepancy: we show that increased neural excitation emerges only after repeated stimulation, manifesting as a deficit in neural adaptation. We measured fMRI responses induced by repeated audio-visual stimulation and button presses in early sensory-motor cortical areas. Across all cortical areas we show reduced adaptation in individuals with ASD compared to neurotypical individuals. The degree of adaptation is correlated between cortical areas and with button-press reaction times across subjects. These findings suggest that increased neural excitation in ASD, manifesting as dysregulated neural adaptation, is domain-general and behaviorally-relevant.

scholarly journals Callous-unemotional traits in youth with autism spectrum disorder (ASD): replication of prevalence estimates and associations with gaze patterns when viewing fearful faces

2020 ◽  
pp. 1-9
Author(s):  
Virginia Carter Leno ◽  
Rachael Bedford ◽  
Susie Chandler ◽  
Pippa White ◽  
Isabel Yorke ◽  
...  
Keyword(s):  
Autism Spectrum Disorder ◽  
Behavioral Problems ◽  
Reaction Times ◽  
Recognition Task ◽  
Autism Spectrum ◽  
Spectrum Disorder ◽  
Emotional And Behavioral Problems ◽  
Cu Traits ◽  
Fearful Faces ◽  
Callous Unemotional

Abstract Research suggests an increased prevalence of callous-unemotional (CU) traits in children with autism spectrum disorder (ASD), and a similar impairment in fear recognition to that reported in non-ASD populations. However, past work has used measures not specifically designed to measure CU traits and has not examined whether decreased attention to the eyes reported in non-ASD populations is also present in individuals with ASD. The current paper uses a measure specifically designed to measure CU traits to estimate prevalence in a large community-based ASD sample. Parents of 189 adolescents with ASD completed questionnaires assessing CU traits, and emotional and behavioral problems. A subset of participants completed a novel emotion recognition task (n = 46). Accuracy, reaction time, total looking time, and number of fixations to the eyes and mouth were measured. Twenty-two percent of youth with ASD scored above a cut-off expected to identify the top 6% of CU scores. CU traits were associated with longer reaction times to identify fear and fewer fixations to the eyes relative to the mouth during the viewing of fearful faces. No associations were found with accuracy or total looking time. Results suggest the mechanisms that underpin CU traits may be similar between ASD and non-ASD populations.

scholarly journals Inversion effects in the perception of the moving human form: A comparison of adolescents with autism spectrum disorder and typically developing adolescents

Autism ◽  
2013 ◽  
Vol 18 (8) ◽  
pp. 943-952 ◽  
Author(s):  
Laura Cleary ◽  
Kathy Looney ◽  
Nuala Brady ◽  
Michael Fitzgerald
Keyword(s):  
Autism Spectrum Disorder ◽  
Human Body ◽  
Reaction Times ◽  
Autism Spectrum ◽  
The Body ◽  
Spectrum Disorder ◽  
Configural Processing ◽  
Typically Developing ◽  
Human Form ◽  
Adolescents With Autism

The “body inversion effect” refers to superior recognition of upright than inverted images of the human body and indicates typical configural processing. Previous research by Reed et al. using static images of the human body shows that people with autism fail to demonstrate this effect. Using a novel task in which adults, adolescents with autism, and typically developing adolescents judged whether walking stick figures—created from biological motion recordings and shown at seven orientations between 0° and 180°—were normal or distorted, this study shows clear effects of stimulus inversion. Reaction times and “inverse efficiency” increased with orientation for normal but not distorted walkers, and sensitivity declined with rotation from upright for all groups. Notably, the effect of stimulus inversion was equally detrimental to both groups of adolescents suggesting intact configural processing of the body in motion in autism spectrum disorder.

scholarly journals Reduced auditory cortical adaptation in autism spectrum disorder

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Rachel Millin ◽  
Tamar Kolodny ◽  
Anastasia V Flevaris ◽  
Alexander M Kale ◽  
Michael-Paul Schallmo ◽  
...  
Keyword(s):  
Autism Spectrum Disorder ◽  
Cortical Neurons ◽  
Visual Stimulation ◽  
Fundamental Property ◽  
Interval Timing ◽  
Autism Spectrum ◽  
Fixed Interval ◽  
Sustained Response ◽  
Spectrum Disorder ◽  
Auditory Cortices

Adaptation is a fundamental property of cortical neurons and has been suggested to be altered in individuals with autism spectrum disorder (ASD). We used fMRI to measure adaptation induced by repeated audio-visual stimulation in early sensory cortical areas in individuals with ASD and neurotypical (NT) controls. The initial transient responses were equivalent between groups in both visual and auditory cortices and when stimulation occurred with fixed-interval and randomized-interval timing. However, in auditory but not visual cortex, the post-transient sustained response was greater in individuals with ASD than NT controls in the fixed-interval timing condition, reflecting reduced adaptation. Further, individual differences in the sustained response in auditory cortex correlated with ASD symptom severity. These findings are consistent with hypotheses that ASD is associated with increased neural responsiveness but that responsiveness differences only manifest after repeated stimulation, are specific to the temporal pattern of stimulation, and are confined to specific cortical regions.

scholarly journals M33. ATTENTUATED POSITIVE SYMPOMS AND FACIAL AFFECT PROCESSING IN HIGH-RISK ADOLESCENTS WITH AND WITHOUT AUTISM

2020 ◽  
Vol 46 (Supplement_1) ◽  
pp. S146-S147
Author(s):  
Arija Maat ◽  
Sebastian Therman ◽  
Hanna Swaab ◽  
Tim Ziermans
Keyword(s):  
Autism Spectrum Disorder ◽  
Cognitive Skills ◽  
Reaction Times ◽  
Autism Spectrum ◽  
Facial Affect ◽  
Spectrum Disorder ◽  
Schizophrenia Spectrum Disorders ◽  
Clinical Predictors ◽  
Schizophrenic Psychosis ◽  
Affect Processing

Abstract Background Autism and schizophrenia spectrum disorders both represent severely disabling neurodevelopmental disorders with marked impairments in social functioning. Despite an increased incidence of psychosis in autism, and substantial overlap in symptoms and cognitive markers, it is unclear whether such phenotypes are specifically related to risk for psychosis or perhaps reflect more general, idiosyncratic autism traits. Attenuated positive symptoms (APS) currently constitute the best and most-replicated clinical predictors of schizophrenic psychosis, and are common in clinical youth with and without autism. The aims of this study were to test the hypothesis that facial affect processing is impaired in adolescents with APS and to explore whether such deficits are more indicative of psychotic or autistic phenotypes on a categorical and dimensional level. Methods Fifty-three adolescents with APS and 81 typically developing controls (aged 12–18) were included. The APS group consisted of adolescents with (n = 21) and without (n = 32) a diagnosis of autism spectrum disorder. Facial affect recognition and ‘lower-level’ cognitive skills, namely pattern and face recognition, were assessed with the Amsterdam Neuropsychological Tasks. For associations with schizotypal and autistic-like traits the Schizotypal Personality Questionnaire and Social Communication questionnaire were used and one-dimensional factor scores were generated with confirmatory factor analysis. Results Our preliminary findings suggest that APS in adolescents is not associated with impairments in pattern, face, or emotion recognition. However, the APS group with autism spectrum disorder generally showed slower reaction times for face/emotional stimuli and they were significantly worse in recognizing fearful expressions than APS participants without autism spectrum disorder and controls. There were no dimensional correlations with schizotypal traits and marginal correlations between autistic-like traits and speed of recognizing faces. Discussion Contrary to our expectations, APS demonstrated limited use in identifying cognitive deficits typical to schizophrenic psychosis. A more autistic-like profile may be characterized by slower reaction times to facial stimuli, suggesting that more complicated and dynamic social cognitive stimuli have a better chance of discerning between autistic and psychotic-like phenotypes.

scholarly journals Implicit and Explicit Memory in Youths with High-Functioning Autism Spectrum Disorder: A Case-Control Study

2021 ◽  
Vol 10 (18) ◽  
pp. 4283
Author(s):  
Elisa Fucà ◽  
Giulia Lazzaro ◽  
Floriana Costanzo ◽  
Silvia Di Vara ◽  
Deny Menghini ◽  
...  
Keyword(s):  
Autism Spectrum Disorder ◽  
Explicit Memory ◽  
High Functioning Autism ◽  
Reaction Times ◽  
Reaction Time Task ◽  
Autism Spectrum ◽  
Spectrum Disorder ◽  
High Functioning ◽  
Sequence Of Events ◽  
Implicit And Explicit Memory

Individuals with autism spectrum disorder (ASD) usually manifest heterogeneous impairments in their higher cognitive functions, including their implicit memory (IM) and explicit memory (EM). However, the findings on IM and EM in youths with ASD remain debated. The aim of this study was to clarify such conflicting results by examining IM and EM using two comparable versions of the Serial Reaction Time Task (SRTT) in the same group of children and adolescents with ASD. Twenty-five youths with high-functioning ASD and 29 age-matched and IQ-matched typically developing youths undertook both tasks. The ability to implicitly learn the temporal sequence of events across the blocks in the SRTT was intact in the youths with ASD. When they were tested for EM, the participants with ASD did not experience a significant reduction in their reaction times during the blocks with the previously learned sequence, suggesting an impairment in EM. Moreover, the participants with ASD were less accurate and made more omissions than the controls in the EM task. The implications of these findings for the establishment of tailored educational programs for children with high-functioning ASD are discussed.

When do individuals with autism spectrum disorder show superiority in visual search?

Autism ◽  
2016 ◽  
Vol 21 (8) ◽  
pp. 942-951 ◽  
Author(s):  
Aya Shirama ◽  
Nobumasa Kato ◽  
Makio Kashino
Keyword(s):  
Autism Spectrum Disorder ◽  
Visual Search ◽  
Visual Processing ◽  
Search Task ◽  
Reaction Times ◽  
Autism Spectrum ◽  
Spectrum Disorder ◽  
Retinal Eccentricity ◽  
Target Feature ◽  
Target Eccentricity

Although superior visual search skills have been repeatedly reported for individuals with autism spectrum disorder, the underlying mechanisms remain controversial. To specify the locus where individuals with autism spectrum disorder excel in visual search, we compared the performance of autism spectrum disorder adults and healthy controls in briefly presented search tasks, where the search display was replaced by a noise mask at a stimulus-mask asynchrony of 160 ms to interfere with a serial search process while bottom-up visual processing remains intact. We found that participants with autism spectrum disorder show faster overall reaction times regardless of the number of stimuli and the presence of a target with higher accuracy than controls in a luminance and shape conjunction search task as well as a hard feature search task where the target feature information was ineffective in prioritizing likely target stimuli. In addition, the analysis of target eccentricity illustrated that the autism spectrum disorder group has better target discriminability regardless of target eccentricity, suggesting that the autism spectrum disorder advantage does not derive from a reduced crowding effect, which is known to be enhanced with increasing retinal eccentricity. The findings suggest that individuals with autism spectrum disorder excel in non-search processes, especially in the simultaneous discrimination of multiple visual stimuli.

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