An Eye Tracking Study Examining the Role of Mating Strategies, Perceived Vulnerability to Disease, and Disgust in Attention to Pathogenic Cues. Ray Garza, Farid Pazhoohi, Laith Al-Shawaf & Jennifer Byrd-Craven. Adaptive Human Behavior and Physiology, March 1 2023. https://link.springer.com/article/10.1007/s40750-023-00211-4
Abstract: Disgust is an emotion that regulates disease avoidance and reduces the likelihood of pathogenic infections. Existing research suggests a bidirectional relationship between disgust and mating, where disgust inhibits sexual behavior and sexual behavior inhibits disgust. In the current study, we investigated the role of individual differences and mating motivations on visual attention to pathogenic cues. Participants (N = 103) were randomly assigned to a mating prime or control condition, and they were asked to view images of pathogenic cues (i.e., rotten food, exposed cuts, bodily fluids) paired with their non-pathogenic counterparts. The findings showed no effect of mating prime on visual attention to pathogenic stimuli; however, dispositional mating strategies (SOI-R) were associated with attention to pathogenic stimuli. Individuals with unrestricted sociosexual orientations viewed pathogenic stimuli longer. The findings demonstrate that dispositional mating orientation is associated with greater attention to disgusting images, a link between pathogens and mating orientation that warrants further exploration.
Discussion
In the current study, we examined if a short-term mating prime and individual differences in short term-mating (i.e., SOI) would predict visual attention to pathogen cues. We tested if short-term mating, whether primed or dispositional, would inhibit attention to pathogen related cues resulting in lower viewing time. We found that participants viewed images containing pathogen cues longer than non-pathogen cues. With respect to the role of mating psychology, the short-term mating prime did not have an effect on visual attention to pathogen related cues. However, individual differences in short-term mating orientation were associated viewing time, with a stronger short-term mating orientation predicting greater viewing time for pathogen cues. Individual differences in pathogen disgust and perceived vulnerability did not predict visual attention to pathogen related cues.
These findings demonstrate that individuals attend more to pathogen-salient compared to non-pathogen salient information. This was shown in looking behavior (number of fixations) and overall attention (dwell time). This bolsters the notion that pathogen cues represent a threat and that attending to that threat may provide individuals with a means to prepare or respond to such stimuli. It has been suggested that attending to threatening information is an automatic and mandatory response (Schmidt et al., 2016), which is an evolved mechanism to be able to monitor threating situations (Belopolsky et al., 2011). For instance, individuals display more visual attention when given a signal that indicates a threatening situation (i.e., signaling a shock) (Nissens et al., 2017) or angry facial expressions (Belopolsky et al., 2011). Individuals also orient their eye movements to threatening stimuli even when instructed to attend to other visual stimuli (Schmidt et al., 2015). Although it has often been suggested that attending to threatening stimuli is automatic, we did not find that individuals automatically attended to pathogen cues first compared to non-pathogen cues, as we found that first fixation durations were longer for non-pathogen cues. Visual measurements, such as first fixation durations, are supposed to capture automatic responses to a stimulus at the onset of presentation (Conklin et al., 2018). Perhaps pathogen cues represent a stimulus that requires intentional visual processing to determine whether or not the pathogen represents immediate threat based on our experience with a type of pathogen exposure (i.e., mucus running down a person’s face).
The mating prime was not associated with attention to pathogen cues. This finding suggests that experimentally inducing short-term mating through a hypothetical mating prompt does not downregulate one’s attention to pathogen cues. There was a positive association between individual differences in short-term mating and visual attention (i.e., number of fixations, dwell time) to pathogen cues. Contrary to our expected predictions, individuals with a propensity to engage in uncommitted sexual encounters did not show reduced attention to viewing pathogen cues. The reasons for this finding are unclear. One possibility is that people with stronger short-term mating orientation, who often have lower disgust, can afford to look at pathogens more closely or for longer without being as strongly affected as their more easily disgusted counterparts. Considering that individuals with a short-term mating orientation prioritize partners with putative indicators of high-quality genes (Buss & Schmitt, 1992), they may be attentive to cues that indicate a higher level of pathogen presence in order to choose the best fit mate and avoid unfit partners. Interestingly, this relationship was seen in the sample of women. Research has shown that women are more easily disgusted than men, on average (Al-Shawaf & Lewis, 2013; Al-Shawaf et al., 2016, 2015; Curtis et al., 2004; Tybur et al., 2012). Since women may suffer greater costs (e.g., the possibility of passing an infection on to dependent offspring) in contracting pathogens, they may be more attentive to pathogen related information when engaging in short-term mating behaviors. Compared to males, females have a greater minimum obligatory parental investment and incur a greater cost in in mating decisions (Trivers, 1972). Therefore, displaying a heightened attentional response to potentially threating cues may be an adaptive response for women who are oriented toward uncommitted sexual behaviors. Conversely, individuals with a lower short-term mating orientation (i.e., more restricted sociosexuality) were less likely to view pathogen cues. This may suggest that individuals who are less likely to engage in uncommitted sexual behaviors or pursue multiple sexual opportunities are more likely to avoid pathogen cues and avoid looking at them. Individuals with a lower propensity for short-term mating are more likely to report higher levels of disgust (Al-Shawaf et al., 2015), and this may result in them looking away from disgusting stimuli. These interpretations should be taken with caution, as they are preliminary and need to be replicated in addition to testing alternative explanations. Finally, individual differences in pathogen disgust and perceived vulnerability were not associated with greater attention to pathogen cues. Previous research has suggested that individuals who report higher disgust and feel more vulnerable to disease have a heightened response system (Safra et al., 2021), making them more vigilant and aware of threat-related stimuli (Mahkanova & Shepard, 2020), such as pathogen cues. However, in the present study, the two measures of trait-level pathogen avoidance were not associated with differences in the amount of attention paid to pathogen cues.
Overall, these findings show that individuals display more attention to pathogen-related cues compared to non-pathogen cues. This finding is in line with the general principle that humans have evolved cognitive mechanisms that are designed to detect recurrent adaptive threats, including avoiding pathogens. Detecting pathogen-related information in an environment would have been beneficial throughout ancestral conditions, and it is still important in modern times. The cognitive mechanisms that are involved, such as attention, help individuals make assessments of the potential threat, and perhaps may influence decision making systems.
There are several limitations to this study. First, The mating prime, which consisted of asking participants to imagine themselves in a hypothetical scenario, may not have been an effective mating prime manipulation. It is possible that a stronger or more ecologically valid mating manipulation may inhibit disgust more effectively – consequently, using other mating manipulations (i.e., images, videos) is warranted. Second, our sample represents another limitation – for this methodologically intensive eye-tracking study, we relied primarily on a sample of WEIRD university students. Curtis et al. (2004) showed that disgust sensitivity declines with age, therefore, it is important to attempt to replicate these findings with older adults and with participants from different cultures. However, Raifee et al. (2022) did not find any evidence for age-related declines in pathogen disgust. Third, in this study we only tested the role of short-term mating and its association with viewing pathogen cues. It is possible that priming pathogen cues may reduce interest in short-term mating opportunities, and this may be dependent on one’s dispositional short-term mating orientation. Perhaps an eye-tracking study with separate blocks testing each mechanism (short-term mating – pathogen cues, pathogen cues – short-term mating) can help clarify those relationships. Fourth, this study was conducted at the onset of Covid-19 infections. It is possible that disgust sensitivity was heightened due to rising infections, which may have increased pathogen cue attention. Finally, this study shows that those with a stronger short-term mating orientation attend to pathogens longer, but it remains to be seen whether those with a stronger long-term mating orientation display similar or different attentional response systems (STM and LTM orientation appear to be two different constructs and not merely opposite ends of the same continuum; see Jackson & Kirkpatrick, 2007). This represents a useful future direction for researchers interested in the relationship between mating orientation, disgust, and how this connection may manifest itself through attention to visual stimuli.