Social Information Processing in the Vomeronasal System during Active Behavior - Project Summary/Abstract Animals combine sensory information and prior experiences to select and adapt behavior. How the brain supports this ability is unknown, and this question is advantageously addressed through investigations of mouse social behavior. In mice, social behaviors are strongly coupled to the detection of well-defined chemosignals (e.g., pheromones), are stereotypical across individuals, and are robustly modulated by an animal’s history. These features provide an excellent framework to define behaviorally-relevant brain areas and investigate the underlying neural mechanisms of sensory-guided, flexible behavior. Indeed, previous studies implicate the accessory olfactory bulb (AOB) in regulating social behaviors, but technical limitations have precluded the ability to record activity during naturalistic interactions among freely-moving conspecific partners. Thus, our understanding of how social behavior shapes ongoing neural activity and how this activity, in turn, guides social behavior during active behavior remains limited. This proposal incorporates several innovative experimental strategies and technological advances to deepen our understanding of the neural dynamics and network architectures that support social behavior. Specifically, I will first use head-mounted miniature microscopes (“miniscopes”) to determine how social information is represented within the AOB of freely-moving mice during prolonged interactions as animals actively engage with a range of conspecific partners and with unique chemosignals. Next, I propose to establish the relationship between AOB activity and intermale aggression. First, through targeted ex vivo recordings and bidirectional chemogenetic manipulations, I will establish the relationship between functionally defined AOB neurons and aggression levels. Next, I will determine how AOB sensory responses are affected by mating; a salient life event that promotes AOB plasticity and increases aggression in male mice. Together, I will establish how neural activity within the AOB adapts in support of flexible behavior. Finally, I propose to define how social information is distributed to downstream, behaviorally-relevant limbic area targets. I will perform multi-site retrograde labeling and pathway-specific manipulations to define how the AOB innervates downstream targets and the behavioral relevance of these pathways. Together, these experiments will provide fundamental information of how the brain represents, modifies, and distributes social information in support of flexible behavior. Moreover, these results will further establish the AOB and related structures as a powerful framework to explore the neural underpinnings of complex behavior.
