Impaired odor identification ability and olfactory hedonic capacity in children with elevated autistic traits

Atypical olfactory function in autism spectrum disorder has been documented in numerous studies, but little is known about its occurrence in individuals with autistic traits. The aim of the current study was to investigate odor identification ability and olfactory hedonic capacity in children with autistic traits. We recruited 415 children and measured their autistic traits by the Short Autism Spectrum Quotient. The Universal Sniff (U-Sniff) test was used to measure odor identification ability and olfactory hedonic capacity. Olfactory hedonic capacity was also measured using the children's version of the Chemosensory Pleasure Scale (CPS-C). Odor identification and olfactory hedonic capacity measured by CPS-C were negatively correlated with autistic traits. Children with higher autistic traits exhibited poorer odor identification ability and olfactory trait hedonic capacity measured by CPS-C but intact olfactory state hedonic capacity measured by odor pleasantness. These results pertaining to odor identification and olfactory hedonic capacity may be the endophenotypic markers for autism spectrum disorder. Practical Applications Our study extends the knowledge on children with high autistic traits and provides a new perspective on olfactory identification ability and olfactory hedonic capacity in children with high autistic traits. In addition, our findings suggest olfactory testing may provide a new approach for detecting and understanding autism.