Pseudo-Contamination and Memory: Is There a Memory Advantage for Objects Touched by "Morphologically Deviant People"?

Memory plays an important role in the behavioral immune system (BIS; Schaller in Psychological Inquiry, 17(2), 96-101, 2016a), a proactive immune system whose ultimate function is to make organisms avoid sources of contamination. Indeed, it has been found that objects presented next to sick people are remembered better than objects shown next to healthy people-representing a contamination effect in memory. In the present studies, we investigated this memory effect in relation to "pseudo-contaminated" sources, that is to say, people exhibiting cues ultimately evoking the threat of contamination but objectively posing no such threat in terms of disease transmission. Common objects were shown next to photographs of people having three kinds of morphological deviations-obesity (study 1), scars and burns (study 2), strange eyes (study 3)-or no morphological deviation. Contrary to our expectations, we found that "pseudo-contaminated objects" were not remembered better than "non-contaminated objects," whereas discomfort ratings of the idea of touching the same objects were clearly higher with morphologically deviant people. Memory mechanisms do not seem to be mobilized by "pseudo-contamination" sources which are not directly related to infection risk.

COVID-19 and Memory: A Novel Contamination Effect in Memory.

The Behavioral Immune System (BIS, Schaller & Park, 2011) is a defense system whose function is to protect against pathogen exposure. Memory is an important component of this system (Fernandes et al., 2017). We investigated "contamination effects" in memory in relation to COVID-19. Photographs of everyday objects were shown to adults (N = 80) in the hands of either a healthy or a contagious person who had contracted SARS-CoV-2. "Contaminated objects" were recalled better than "non-contaminated objects" suggesting that a contamination effect in memory in humans is easily acquired in the absence of apparent visual cues of disease.

"Touch Me If You Can!": Individual Differences in Disease Avoidance and Social Touch.

The threat of diseases varies considerably among individuals, and it has been found to be linked to various proactive or reactive behaviors. In the present studies, we investigated the impact of individual differences in the perceived vulnerability to disease (PVD) on social touch before (Study 1) or during the coronavirus disease 2019 (COVID-19) pandemic (Study 2). We also investigated the influence of personality traits in the covariation between these two dimensions. We found that people who are the most disease-avoidant are also the most reluctant to touching or being touched by others (and this relationship holds when personality traits are taken into account). Interestingly, the association between PVD and social touch increased during the COVID-19 pandemic compared with a few months before. By showing that the fear of contamination has an association with social touch, the findings provide further evidence for the behavioral immune system ( Schaller and Park, 2011), a psychological system acting as a first line of defense against pathogens.