Background Decreased sound tolerance (DST) is common in individuals with autism spectrum disorder (ASD). This study examined how attentional control resources influence DST. Previous studies have shown that increasing cognitive load enhances the brain activity component (N100) to task-irrelevant noise. We hypothesized that individuals with DST would be more sensitive to cognitive load, showing a greater increase in their neural responses to noise as cognitive load increases. Because DST comprises multiple subjective symptoms, we analyzed the associations with specific symptoms. Methods Thirteen adults with ASD and twenty-two adults without ASD participated in the study. Participants who self-reported auditory hypersensitivity were classified as the DST group. All participants completed a DST questionnaire with six subscales: excessive loudness, ear pain, fear, annoyance, attention control, and attention to detail. Event-related potentials (ERPs) elicited by task-irrelevant noise were analyzed during an auditory n-back task. The n-back task included a low (1-back) and a high (2-back) cognitive load condition. Results The prevalence of self-reported DST was significantly higher in the ASD group than in controls. Individuals who reported DST also tended to experience other types of sensory hypersensitivity. Attentional functions were associated with fear, annoyance, and loudness perception of sounds, and ear pain appeared to function independently of other DST symptoms. Scores for attentional control difficulties related to DST did not correlate with performance on the n-back task, which reflects susceptibility to noise interference. Contrary to previous findings, N100 amplitude did not differ between task-load conditions and did not vary according to the presence of DST. P200 amplitude was larger in the 1-back than in the 2-back condition but did not differ by ASD diagnosis or DST status. Conclusions The presence of DST or ASD was not associated with cognitive capacity or with the auditory processing of task-irrelevant noise.
Ito et al. (Sat,) studied this question.