A multilevel investigation of sensory sensitivity and responsivity in autistic adults

A typical sensory processing is a core symptom of autism spectrum disorders (ASD). We aimed at better characterizing visual sensitivity and responsivity in ASD at the self-reported, behavioral and neural levels, and at describing the relationships between these levels. We refer to sensory sensitivity as the ability to detect sensory stimuli and to sensory responsivity as an affective response to sensory stimuli. Participants were 25 neurotypical and 24 autistic adults. At the self-reported level, autistic participants had higher scores of sensory sensitivity and responsivity than neurotypicals. The behavioral and neural tasks involved contrast-reversing gratings which became progressively (in)visible as their contrast or spatial frequency evolved. At the behavioral level, autistic participants had higher detection and responsivity thresholds when gratings varied in spatial frequency, but their thresholds did not differ from neurotypicals when gratings varied in contrast. At the neural level, we used fast periodic visual stimulations and electroencephalography to implicitly assess detection thresholds for contrast and spatial frequency, and did not reveal any group difference. Higher self-reported responsivity was associated with higher behavioral responsivity, more intolerance of uncertainty and anxiety, in particular in ASD. At the self-reported level, higher sensitivity was associated with more responsivity in both groups, contrary to the behavioral level where these relationships were not found. These heterogeneous results suggest that sensitivity and responsivity per se are not simply increased in ASD, but may be modulated by other factors such as environmental predictability. Multi-level approaches can shed light on the mechanisms underlying sensory issues in ASD.

Automated summary

This study aimed to better understand the visual sensitivity and responsivity in individuals with autism spectrum disorders (ASD) at self-reported, behavioral, and neural levels, and to explore their relationships. The results showed that autistic participants had higher scores of sensory sensitivity and responsivity at the self-reported level and exhibited different sensitivity thresholds at the behavioral level. However, there were no group differences in neural assessment of detection thresholds. These findings suggest that sensitivity and responsivity in ASD are not simply increased but may be influenced by other factors such as environmental predictability. Multi-level approaches can provide insights into the mechanisms underlying sensory issues in ASD.