Task-induced pupil response and visual perception in adults.

We assessed whether there are differences in pupil response that underlie the selection of local vs. global parts of a stimulus array in healthy adults. We designed a Navon Figures eyetracking paradigm (i.e. large figure composed of small figures), requiring an individual to vary only the information attended to within an image. We found that participants have a characteristic constriction of the pupil waveform during selection of local information relative to global information. Because stimuli and lighting conditions were identical across conditions, this indicates that pupil changes may serve in a visual filtering mechanism important for attentional selection. This work represents the first characterization of pupil response in the context of selective attention, suggesting that mechanisms underlying the earliest stages of visual processes could be relevant for perception and visual selection.

The Broader Autism Phenotype and Visual Perception in Children.

Atypical visual perception has increasingly been described in individuals with autism spectrum disorders (ASD) and linked to quantitative, autism-like features that are present in children and adults without ASD. We investigated whether individual differences in visual processing skills were related to quantitative measures of autism traits in a pediatric sample with a range of clinical features. Visual processing was comprehensively characterized using the test of visual perceptual skills (TVPS), a standardized test of visual perception with seven subtests that capture a range of visual processing abilities. The TVPS Figure Ground (TVPS-FG) subtest requires an individual to disembed a smaller figure from a larger scene. TVPS-FG subtest scores were positively correlated with children's autism features as measured by a parental report of the Broader Autism Phenotype Questionnaire (BAP-Q). The correlation with BAP-Q was specific to the TVPS-FG subtest, as the other TVPS subtest scores were not significantly related to the BAP-Q. This adds to the growing body of research documenting that atypical visual processing is associated with the autism phenotype and highlights the importance of capturing quantitative traits in heterogeneous developmental brain disorders.

Brief Report: Autism-like Traits are Associated With Enhanced Ability to Disembed Visual Forms.

Atypical visual perceptual skills are thought to underlie unusual visual attention in autism spectrum disorders. We assessed whether individual differences in visual processing skills scaled with quantitative traits associated with the broader autism phenotype (BAP). Visual perception was assessed using the Figure-ground subtest of the Test of visual perceptual skills-3rd Edition (TVPS). In a large adult cohort (n = 209), TVPS-Figure Ground scores were positively correlated with autistic-like social features as assessed by the Broader autism phenotype questionnaire. This relationship was gender-specific, with males showing a correspondence between visual perceptual skills and autistic-like traits. This work supports the link between atypical visual perception and autism and highlights the importance in characterizing meaningful individual differences in clinically relevant behavioral phenotypes.

Late Positive Potential ERP Responses to Social and Nonsocial Stimuli in Youth with Autism Spectrum Disorder.

We examined the late positive potential (LPP) event related potential in response to social and nonsocial stimuli from youths 9 to 19 years old with (n = 35) and without (n = 34) ASD. Social stimuli were faces with positive expressions and nonsocial stimuli were related to common restricted interests in ASD (e.g., electronics, vehicles, etc.). The ASD group demonstrated relatively smaller LPP amplitude to social stimuli and relatively larger LPP amplitude to nonsocial stimuli. There were no group differences in subjective ratings of images, and there were no significant correlations between LPP amplitude and ASD symptom severity within the ASD group. LPP results suggest blunted motivational responses to social stimuli and heightened motivational responses to nonsocial stimuli in youth with ASD.