Olfactory scene analysis: Does analytical visual processing predict superior identification of component odours in a complex mixture?

Abstract

Most familiar odours are complex mixtures of volatile molecules, which the olfactory system synthesizes into a perceptual whole. However, odours are rarely encountered in isolation and thus, the brain must also separate distinct odour objects from complex backgrounds. While in vision, individual differences in scene analysis have been widely reported, to date, little attention has been paid to the cognitive processes underlying this olfactory ability. The aim of the present study was to determine whether local processing performance in visual tasks predicts participants' ability to identify component odours in multicomponent mixtures. Fifty-nine participants (F = 39), aged 16-55, completed two visual perception tasks, (Navon and Block Design), an odour-mixture task designed to test participants' ability to identify multi-component odour objects in binary/ternary mixtures and the Autism Quotient (AQ) Questionnaire, which measures autistic traits in the general population. While performance indices on neither visual task, nor scores on the AQ, were associated with odour mixture task performance, there was moderate evidence to support an association between reaction time on the Navon task and binary odour mixture task performance. These results provide insight into the cognitive processes underpinning olfactory scene analysis and support previous reports that faster processing speed is associated with superior selective attention.