We now know that disgust sensitivity is heritable, and that parental modeling does not appear to shape it; but idiosyncratic experience does shape it

Tybur, Joshua M., and Annika Karinen. 2019. “Measurement and Theory in Disgust Sensitivity.” PsyArXiv. October 29. doi:10.31234/osf.io/64fvp

Abstract: This chapter covers the 20+ year history of disgust sensitivity research by summarizing and contrasting different disgust sensitivity instruments and discussing how these instruments are used and interpreted.

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Surveys conducted in the United States show that people report disgust toward actions and objects that inhabit some of the most important corners of our lives. We are disgusted by the prospect of eating certain foods, the sights and smells of other people’s bodies, the thought of sexual contact with most of the people on earth, and considerations of others’ moral shortcomings (Haidt et al., 1994; Tybur et al., 2009). International surveys indicate that disgust’s relevance to food choice, mating, and morality is not a quirk of US culture (Curtis and Biran, 2001; Haidt et al., 1997; cf. Kollareth and Russell, in 2017). Despite disgust’s far-reaching consequences, only scarce work was devoted to understanding the emotion through most of the twentieth century (Rozin et al., 2009). In the 1990s, however, the dearth of research to the topic caught the attention of a handful of scientists, who described disgust as both the ‘forgotten emotion of psychiatry’ (Phillips et al., 1998) and as a scarcely investigated – yet key – cog in the mechanisms that underlie our moral psychology (Haidt et al., 1993; Haidt et al., 1997). Calls for greater interest in disgust were heard across the behavioral sciences, with researchers using the science of disgust to better understand political attitudes (Inbar et al., 2012), food preferences (Fessler et al., 2003), health behavior (Reynolds et al., 2014), personality (Tybur and De Vries, 2013), psychopathology (Olatunji and Sawchuk, 2005), aggression (Pond et al., 2012), and moral judgments (Chapman and Anderson, 2013, 2014).

Although much of this work on disgust has focused on understanding the psychological processes underlying disgust and their resulting effects on behavior (e.g., Tybur and Lieberman, 2016), the majority of disgust research has focused on individual differences. Largely using self report instruments, researchers have tested how disgust sensitivity (DS) – that is, reported intensity of disgust toward the types of things that arouse at least a little disgust in most healthy adults – relates to the variety of topics detailed earlier. Results from these studies portray the disgust sensitive individual as someone who is averse toward new experiences (Tybur and De Vries, 2013), politically conservative (Inbar et al., 2012), prone to moral judgment (Chapman and Anderson, 2014), and more likely to have anxiety disorders (Olatunji and Sawchuk, 2005). Relative to the prodigious measurement of DS, though, little work has critically analyzed the validity of the multiple DS instruments used in the literature and the nature of DS as a construct. This chapter aims to provide a survey of the DS literature and, in doing so, comment on the dimensionality of DS, the mechanistic roots of DS, the developmental origins of DS, and a theoretical framework that can organize the literature.


Concluding thoughts

Researchers have been excited to find that DS relates to phenomena such as political ideology and psychopathology. Such findings promise to provide novel understandings of why individuals adopt liberal vs. conservative political positions, or why they experience potentially debilitating anxieties about washing and cleansing. The potential knowledge gleaned from these studies is constrained by our understanding of DS itself, though. Much recent progress has been made in understanding disgust as an emotion, and in understanding the dimensionality of DS, relation with personality, and heritability. Every slice of new information about DS can raise further questions. We now know that DS is heritable, and that parental modeling does not appear to shape DS. But what are the genetic and environmental sources shaping DS? Pathogen DS appears to relate to behavioral avoidance of pathogen cues, but perhaps not facial responses to pathogen cues. Do null relations with facial response reflect a disjunction between experienced and expressed disgust, or do they reflect underpowered studies? And, further, what differentiates pathogen DS from other variables used in the behavioral immune system literature, and what differentiates sexual DS from sociosexuality? Questions like these suggest that DS research has entered a second generation of sorts – it has matured from a new venture that shows promise for understanding a variety of phenomena to a multidisciplinary undertaking dedicated to understanding dimensionality, development, and cross-cultural variation. We hope that this chapter has sketched out promising directions for this second generation of research, and that future overviews of DS can provide answers to some of the questions posed.