Divergent medial amygdala circuits for resolving approach-avoidance conflict

Abstract

Avoidance of innate threats is often conflicted by motivations to engage in exploratory approach behavior. The neural circuits that underlie this approach-avoidance conflict are not well resolved. Here, we isolated a population of dopamine D1 receptor (D1R) expressing neurons within the posteroventral region of the medial amygdala (MeApv) in mice that are activated either during approach or during avoidance of an innate threat stimulus. Distinct subpopulations of MeApv-D1R neurons differentially innervate the ventromedial hypothalamus (VMH) and bed nucleus of the stria terminalis (BNST) and these projections have opposing effects on investigation or avoidance of threatening stimuli. These circuits are potently modulated through opposite actions of D1R signaling that bias approach behavior. These data demonstrate divergent pathways in the MeApv that can be differentially weighted towards exploration or evasion of threats.