EXPLORING THE ROLE OF THE PL-NAC PATHWAY IN PROSOCIAL AND SELFISH BEHAVIORS

Social animals frequently face decisions between selfish actions that benefit themselves and prosocial actions that benefit others. However, the neural circuits underlying these behaviors remain poorly understood. Although the prelimbic cortex (PL) and nucleus accumbens (NAc) have been independently implicated in decision-making, reward processing, and social behavior, their interaction during social decision-making remains unknown. Our recent findings demonstrate correlated activity between PL and NAc during prosocial and selfish decisions, suggesting a functional interaction. In this study, we evaluated the role of PL-NAc projection during social decisions in CD1 mice using chemogenetic techniques to selectively inhibit the projection of the PL to the NAc during social decision-making. Mice were trained in a two-choice task in which lights signaled either a prosocial option, delivering a reward to a familiar conspecific, or a selfish option, delivering a reward only to the subject. Additionally, forced-choice training ensured mice explored both options before showing a preference. Once the mice exhibited a ≥70% preference for either outcome, compound 21 (C21) was administered to inhibit the PL-NAc projection during testing. Data were compared with a saline-injected control group. Preliminary results show that mice injected with C21 exhibited a modest reduction in preference for both prosocial and selfish choices compared with saline-treated mice, while mice with no initial preference were unaffected. These findings suggest that the PL–NAc projection may contribute broadly to decision-making processes, independent of the social outcome. Additional analyses will evaluate whether these reductions are attributable to impairments in social memory.