Measurement and Theory in Disgust Sensitivity

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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Behavioral Validations of DS

As its name implies, pathogen disgust is associated with motivations that appear tailored
to keeping pathogens at bay. Consider the canonical disgust face, which is characterized by (1) a
closing of the eyes and, a lowering of the eyebrows, both of which reduce the exposed surface
area of the eyes, (2) a wrinkling of the nose, which reduces air intake, and (3) a lowering of the
lips, which reduces the probability of objects entering the mouth (or, alternatively, if something
is already in the mouth, a protruding tongue, which expels the contents of the mouth; Susskind et
al., 2008). Each of these actions partially seals off an entryway through which pathogens can
enter the body. Behaviors apart from facial expression also appear specialized for neutralizing
pathogens. Disgust is associated with motivations to avoid physical contact with the disgust
elicitor – physical contact that would allow pathogens to be transmitted from disgust elicitor to
human (Hertenstein et al., 2006; Roseman et al., 1994). Does pathogen DS, as assessed by selfreport instruments, relate to these types of pathogen-neutralizing behaviors?
Multiple studies employing behavioral avoidance tasks (BAT) suggest that it does. In
BATs, researchers record whether participants are willing to physically contact an object, and
what degree of contact they will engage in. For example, in one study, participants were
presented with a cookie on the floor and were asked to (a) hold the cookie, (b) touch the cookie
with their lips, and (c) eat the cookie (Deacon and Olatunji, 2007). Similar progressions were
used for a used hair comb and a bedpan filled with toilet water. Pathogen DS (negatively)
predicted the number of steps completed in the tasks, even when controlling for participant sex,
anxiety, and depression. Similar results have been obtained for BATs in which participants were
asked to touch tissues used by someone who had the common cold (Fan and Olatunji, 2013);
touch a sterilized cockroach (Rozin et al., 1999); touch a colonoscopy bag (Reynolds et al.,
2014); and touch moldy fruit (Olatunji, Lohr et al., 2007). In contrast, pathogen DS does not
predict avoidance of watching or committing socio-moral violations (Van Overveld et al., 2010),
and sexual DS and moral DS do not predict avoidance of contact with sinks, trash cans, and
toilets in a public restroom (Olatunji et al., 2012). Similarly, pathogen DS – but not sexual DS or
moral DS – relates to galvanic skin response to images of pathogen cues (Olatunji et al., 2012).
Only a few studies have tested whether DS relates to facial responses to disgust-eliciting
stimuli. In one study of 47 participants, facial electromyography (EMG) indicated that pathogen
DS was unrelated to the degree of levator labii (a key muscle in the disgust facial response)
activation in response to disgust-eliciting images (Stark et al., 2005). In another study of 60
participants, EMG again indicated that pathogen DS was unrelated to levator labii activation in
response to a disgust-eliciting film clip (De Jong et al., 2011). Of course, these studies are not
well powered to detect small relations between DS and facial responses – they only had 28% and
34% power to detect a correlation of r = 0.25. Nevertheless, they hint at two interesting
possibilities. First, they could suggest that variability in some anti-pathogen responses, including
subjective feelings of disgust and physical avoidance, is distinct from variability in other anti-
pathogen responses, such as reducing the degree to which the eyes, nose, and mouth are exposed
to pathogens. Second (and, perhaps, alternatively), they could suggest that variability in facial
response to disgust elicitors reflects variability in motivations to communicate the presence of
pathogens to others (see Fridlund, 1991). Once again, further research is needed to adjudicate
between these possibilities.
The majority of studies testing how DS relates to behavior have presented participants
with cues to pathogens. One exception examined how DS relates to aggression. Reasoning that
disgust motivates avoidance – and that aggression involves approach-oriented motivations
(Harmon-Jones and Peterson, 2008) – Pond and colleagues (2012) suggested that DS should
relate negatively to aggression. They found that participants higher in moral DS and in sexual DS
– but not pathogen DS – delivered fewer high intensity noise-blasts in a behavioral aggression
paradigm (notably, though, this study did not report unique effects of moral DS vs. sexual DS,
and it did not control for participant sex – a variable strongly related to both aggression and
sexual DS). That said, we are unaware of any studies that have examined how sexual DS relates
to behavioral responses to unwanted sexual advances or how moral DS relates to behavioral
responses to individuals who have committed moral transgressions. Naturally, such studies
present ethical challenges that surpass asking participants to touch tissues or sterilized
cockroaches. Nevertheless, they would greatly improve our interpretation of sexual DS and
moral DS.
In sum, findings gleaned from a variety of methods – including self-report instruments,
behavioral avoidance tasks, and physiological measures – provide the groundwork for how we
should interpret DS. However, a theoretical framework is required to integrate these empirical
findings and transform this groundwork into a firm foundation. In the next section, we will extend
a theoretical framework for understanding the experience of disgust (Tybur et al., 2013) to
understanding variability in DS.