Moral judgment modulation by disgust is bi-directionally moderated by individual sensitivity

Abstract

Modern theories of moral judgment predict that both conscious reasoning and unconscious emotional influences affect the way people decide about right and wrong. In a series of experiments, we tested the effect of subliminal and conscious priming of disgust facial expressions on moral dilemmas. “Trolley-car”-type scenarios were used, with subjects rating how acceptable they found the utilitarian course of action to be. On average, subliminal priming of disgust facial expressions resulted in higher rates of utilitarian judgments compared to neutral facial expressions. Further, in replication, we found that individual change in moral acceptability ratings due to disgust priming was modulated by individual sensitivity to disgust, revealing a bi-directional function. Our second replication extended this result to show that the function held for both subliminally and consciously presented stimuli. Combined across these experiments, we show a reliable bi-directional function, with presentation of disgust expression primes to individuals with higher disgust sensitivity resulting in more utilitarian judgments (i.e., number-based) and presentations to individuals with lower sensitivity resulting in more deontological judgments (i.e., rules-based). Our results may reconcile previous conflicting reports of disgust modulation of moral judgment by modeling how individual sensitivity to disgust determines the direction and degree of this effect.

Does Incidental Disgust Amplify Moral Judgment? A Meta-Analytic Review of Experimental Evidence

“…Participants' ratings of the wrongness of the described transgressions did not differ as a function of the presence or absence of the conditioned word (David & Olatunji, 2011). Lastly, when participants were subliminally primed with disgust facial expressions, they actually rated utilitarian harmsi.e., directly killing one person to save several othersas less morally wrong, contra Schnall, Haidt, et al, though this was moderated by disgust sensitivityhighly sensitive participants rated the harms as less wrong, while less sensitive participants rated them as more wrong (Ong, Mullette-Gillman, Kwok, & Lim, 2014).…”

Does incidental disgust amplify moral judgment? A meta-analytic review of experimental evidence

“…Participants' ratings of the wrongness of the described transgressions did not differ as a function of the presence or absence of the conditioned word (David & Olatunji, 2011). Lastly, when participants were subliminally primed with disgust facial expressions, they actually rated utilitarian harms -i.e., directly killing one person to save several others -as less morally wrong, contra Schnall, Haidt, et al, though this was moderated by disgust sensitivity -highly sensitive participants rated the harms as less wrong, while less sensitive participants rated them as more wrong (Ong, Mullette-Gillman, Kwok, & Lim, 2014).…”

“…There were only two exceptions. First, Ong et al (2014) found that disgust increased during the experiment in both their disgust-prime and neutral-prime conditions.…”

Modulation of incentivized dishonesty by disgust facial expressions

“…Early work suggested that disgust increases the severity of moral judgments by encouraging rule-based (deontological) over utilitarian thinking (Schnall et al, 2008a , b ). However, a number of other studies have since contradicted these initial findings (La Rosa et al, 2012 ; Ugazio et al, 2012 ; Ong et al, 2014 ).…”

“…We recently specified that disgust primes modulate judgments of moral dilemmas based upon a third variable: individual sensitivity to disgust (Ong et al, 2014 ). In this series of experiments, we confirmed that disgust primes modulated the acceptability ratings of utilitarian actions.…”