Subthalamic Nucleus Optogenetic Inhibition Bidirectionally Regulates Social Motivation According to Familiarity and Social Hierarchy

Background: Social behavior is a core component of mental health, and its disruption characterizes many neuropsychiatric disorders such as autism. Social operant paradigms enable the quantification of volitional aspects of social motivation and interactions. While sex differences have been shown to influence social motivation, factors such as familiarity and social hierarchy are also likely to play a critical role that remain insufficiently explored. In addition, the subthalamic nucleus (STN), traditionally studied in motor circuits, has emerged as an important regulator of reward and motivational processes and may contribute to social behavior processes. Methods: In this study, we examined