A systematic review and meta-analysis of the relationship between sensory processing differences and...

There is evidence to suggest that sensory processing differences (SPDs) to external stimuli are a plausible underlying mechanism for mental health problems among autistic people. In the current systematic review, we examined the associations between, on the one hand, eleven types of SPDs and, on the other hand, internalising and externalising problems. The literature search was conducted on five databases (MEDLINE, PsycINFO, Web of Science, EMBASE, and CINAHL) between 1990 and August 2024. Studies with autistic people aged under 65 years-old that reported correlations between SPDs and internalising/externalising problems were included. Three-level and random-effects meta-analyses and narrative synthesis were conducted. In total, we included 63 articles (11,659 participants) in the current review. Overall, higher levels of all SPD subtypes were found to be associated with greater internalising/externalising problems. Hypersensitivity, visual, auditory, and tactile sensitivities were strongly associated with internalising/externalising problems, while smaller effects were observed for unusual processing of smell and taste. Sensation seeking was highly linked with externalising problems, whereas it was the least associated sensory subtype with internalising problems. Future studies could address the limitations in the extant literature (e.g., heterogeneity in the estimates of associations, a lack of externalising problem investigations and longitudinal studies) to further advance our understanding of the role of SPDs in the aetiology, development, and treatment of internalising/externalising problems in autism.