Temporal resolution relates to sensory hyperreactivity independently of stimulus detection sensitivity in individuals with autism spectrum disorder

BackgroundResearchers have been focused on perceptual characteristics of autism spectrum disorder (ASD) in terms of sensory hyperreactivity. Previously, we demonstrated that temporal resolution, which is the accuracy in differentiating the order of two successive vibrotactile stimuli, is associated with the severity of sensory hyperreactivity (Ide et al. 2019). Herein, we examined whether an increase in the perceptual intensity of a tactile stimulus, despite its short duration, is derived from high temporal resolution and a high frequency of sensory temporal summation. MethodSixteen participants with ASD and fifteen typically developing (TD) participants performed two psychophysical experimental tasks, and we evaluated the detectable duration of vibrotactile stimuli with the same amplitude and temporal resolution. Sensory hyperreactivity was estimated using a self-reported questionnaire. ResultsThere was no relationship between temporal resolution and the duration of detectable stimuli in either group. However, the ASD group showed more severe sensory hyperreactivity in daily life than the TD group did, and ASD participants with severe sensory hyperreactivity tended to have high temporal resolution but not high sensitivity for detectable duration. ConclusionContrary to our hypothesis, there might be different processing between temporal resolution and sensitivity for stimulus detection. Sensory reactivity in daily life would not be based on sensitivity for stimulus detection measured in an experimental task, and we suggest that atypical temporal processing would affect sensory reactivity in ASD. Keywords (within 6 keywords): Temporal resolution, Temporal summation, Autism spectrum disorder, Hyperreactivity, Gap detection