An investigation of the three-tier relationships between distaste, disgust expression recognition, and moral responsivity

Abstract

Disgust is a negative and universal basic emotion that is elicited by a diverse set of sources, ranging from concrete physical sources (e.g. bad tastes, disease, feces) to abstract social sources (e.g. moral transgressions and the transgressors). The present study investigated the potential three-tier relationships between distaste (the proposed evolutionary origin of disgust), disgust sensitivity assessed by facial disgust recognition measures, and moral responsivity to explore whether: (a) more sensitive bitter tasters had greater facial disgust recognition accuracy, (b) more sensitive bitter tasters had greater moral responsivity, and (c) more morally sensitive individuals had greater facial disgust recognition accuracy. The bitter taste sensitivity test of 6-n-propylthiouracil (PROP), a standard basic Emotion Recognition Task (ERT) (Young et al., 1997) to measure facial disgust accuracy (“hits”), bias, and false positive errors, and a questionnaire to assess moral judgments of fairness transgressions from a standardized set compiled by Knuston et al. (2010) in addition to the moral disgust subscale from The Three Domain Disgust Scale (TDDS) (Tybur et al., 2009) were administered to 110 participants. Results showed that more sensitive bitter tasters had greater facial disgust bias rates and a trending association with increased disgust false positive error rates. There was no significant relationship found between bitter taste sensitivity and moral responsivity. Interestingly, individuals who found the fairness transgressions less morally inappropriate had a greater tendency to make more facial disgust false positive errors. These findings indicate that there are different levels at which distaste, disgust (in the form of facial disgust recognition dimensions), and moral responsivity are interrelated, providing insight into the multifaceted roles of disgust.