Behavioral, psychopharmacological and gender effects of stress on parochial altruism

• Applicant: Professor Tobias Kalenscher, Ph.D.
• Subject Area: General, Cognitive and Mathematical Psychology ; Human Cognitive and Systems Neuroscience ; Social Psychology, Industrial and Organisational Psychology
• Term: from 2013 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 234237886

Humans are social animals who cooperate with others, consider their well-being and accept personal costs to help them. However, selfless behavior is not always directed at increasing the well-being of other people. Sometimes, individuals accept costs to inflict harm on others, even if harming others does not result in higher own-payoff. Altruistic ingroup cooperation together with outgroup aggression, so-called parochial altruism, is widespread and the underlying cognitive, neural and endocrine mechanisms possibly coevolved. In a first funding phase, we have obtained behavioral and psychopharmacological evidence that stress modulates social discounting, i.e., social-distance-dependent levels of generosity. We have shown that stress selectively increases generosity towards socially close others (family, friends and other ingroup members), but not socially remote others (neighbors, strangers etc.). Interestingly, correlational data from our first study as well as psychopharmacological evidence from a second study suggests that the noradrenergic component of the endocrine stress response may decrease, rather than increase, generosity towards others, suggesting that there is more to the behavioral stress response than mere generosity. Moreover, there is remarkable consensus across disciplines that stress can also increase aggressive tendencies, e.g., fighting responses. We therefore hypothesize that the stress-related increase in generosity towards socially close people (ingroup) goes along with an increase in altruistic aggression against outgroup members. Moreover, it has been hypothesized that changes in generosity and/or aggression after stress are gender-dependent, although evidence for gender differences is far from clear. In a second funding phase, we therefore apply for funding to investigate the behavioral, neuroendocrine and gender effects of stress on parochial altruism. We will exploit a natural ingroup-outgroup structure to study realistic intergroup rivalry: existing rivalries between political party voters. We will employ several behavioral tasks allowing us to address 1) whether parochialism is different between men and women in general, i.e., in the absence of stress, 2) whether psychosocial stress, elicited using the group version of the Trier Social Stress Test, amplifies ingroup cooperation together with outgroup hate, and 3) whether these stress-effects on parochialism are gender-dependent. Finally, we predict that enhancing sympathetic (noradrenaline), but not necessarily glucocorticoid activity (cortisol) by psychopharmacological means mimics the effects of stress on parochial altruism. Our proposed studies will refine our understanding of the social response to stress, and gender differences therein, but they may be generalized to yield important insights into the factors promoting and maintaining intergroup conflicts as well as antisocial behavior.

• DFG Programme: Research Grants
• International Connection: United Kingdom
• Cooperation Partners: Professorin Molly Crockett, Ph.D.; Professorin Dr. Nadira Faber