Patterns of sensory modulation by age and sex in young people on the autism spectrum

Sensory modulation symptoms form a diagnostic criterion for autism spectrum disorder and are associated with significant daily functional limitations. Utilizing caregiver report on Short Sensory Profile-2 (SSP-2) for 919 autistic children (3-14.11 years), we examined the expression of sensory modulation symptoms by age and sex and investigated the existence of specific sensory modulation subtypes. Sensory modulation symptoms appeared to peak in frequency during middle childhood, particularly in sensory sensitivity and avoidance. Symptoms associated with sensory hypo-reactivity and seeking tended not differ between age cohorts. Males and females demonstrated similar overall sensory modulation profiles, however, females showed elevated symptoms relating to sensory sensitivity. Model-based cluster analysis revealed five interpretable sensory modulation subtypes which related to symptom severity (low, mid-range, high). Subtypes demonstrating mid-range symptom severity differed in focus on sensory hyper-reactivity or seeking symptoms. The findings of this study report for the first time that age-related differences in sensory modulation symptoms may be associated with sensory hyper-reactivity only. The subtyping results also suggest that sensory modulation symptom severity is a reliable means of classifying variance within autistic children, however, consideration of differences in the behavioral strategies employed by individuals to manage sensory modulation symptoms may inform tailored supportive strategies. LAY SUMMARY: We studied sensory symptoms such as over-responding, under-responding and sensation seeking behaviors in 919 autistic children and adolescents. We found that 6-12-year-olds and females displayed the most sensory over-responding symptoms. Autistic children could be grouped into mild, moderate, and severe levels of sensory symptoms, however, children differed in the type of strategies used to cope with their sensory symptoms meaning that they may require different intervention approaches.