The Association Between Quinine Hydrochloride Sensitivity and Disgust Proneness in Children and Adults

Abstract

Introduction: Humans are very sensitive to several bitter compounds, although there is great inter-individual variability in the elicited emotional (e.g., disgust) and somatic (e.g., nausea) responses. The variability might be associated with the personality trait “disgust proneness” (DP; general tendency to respond with the emotion of disgust). Method: This study examined the relationship between the sensitivity to quinine hydrochloride and DP in children (63 boys and 67 girls; mean age = 8.5 years) and adults (107 men, 95 women; mean age = 29.4 years). Each participant rated the perceived taste intensity of four gustatory stimuli (sucrose, 0.4 g/ml; sodium chloride, 0.25 g/ml; quinine hydrochloride, 0.006 g/ml; citric acid, 0.3 g/ml) and completed questionnaires that assessed the proneness to experience disgust, anxiety, and depressed mood. Results: The computed multiple linear regression analyses for the adults showed that DP but no other trait measure was associated with bitter sensitivity. In children, depression proneness and age were predictors of bitter sensitivity. Conclusions: This study revealed age-dependent correlations between DP and bitter sensitivity. Implications: This finding points to the dynamic features of taste sensitivity (and possibly DP) across the lifespan. Therefore, longitudinal studies are warranted.