Studying the role of the human habenular system in social hierarchy

点击翻译按钮获取中文摘要

Although our social status and ranks often define who we are and are an integral part of our daily life (at home, at school, at work, etc.), we still know fairly little about how our brain processes information about social hierarchy. Social hierarchy, which is often established through social conflicts, is a universal phenomenon and plays a central role in optimal functioning of social species including humans. Importantly, to navigate social environments characterized by social hierarchy, our brain has to: identify the outcomes of social conflictswho has won/lost and thus as gained higher/lower status; learn and update information about social hierarchy; and choose the best actions to produce in a social hierarchy context. This research program aims at studying each of these cognitive abilities and their interactions to gain a better understanding of the neural processes supporting social hierarchy and its influence on behavior and decision-making. We propose that the habenula, a small brain structure of the epithalamus that acts as a hub between cognitive and affective brain systems, plays a key role in these three abilities. To study the neural underpinnings of social hierarchy and its influence on human behavior, we will use an innovative approach combining behavioral tasks specifically designed to elicit social hierarchy processing and behavioral modelingthe use of mathematical models to describe how individuals make decisions. To measure brain activity during these tasks, we will use high-resolution functional magnetic resonance imaging (fMRI) tailored for the study of small brain structures such as the habenula. We will study the general population and, importantly, military personnel who work in highly hierarchical contexts and are thus ideally suited to investigate short and long term behavioral and neural changes related to social hierarchy.This research program will provide the scientific community with new and valuable knowledge about the processing of social hierarchy by investigating outcome coding, learning and decision-making and how these processes interact. Importantly, several types of organizations (military, emergency units, industry) rely on small groups of individuals that have to work in isolation and in which social hierarchies are bound to be formed. Adequate functioning of these small teams surely depends in part on how each member processes social hierarchy. By describing the brain mechanisms that support social hierarchy and how they can change, this research program will provide scientific bases for the development of training aimed at favoring optimal functioning in these small teams.