Grant: Discovery Grants Program - Individual

Behaviours during peer-to-peer social encounters are critical for reproduction and survival in social species, including mice and humans. Of particular significance, are decisions related to assuming a dominant versus subordinate strategy within a social group. These decisions depend on a complex integration of several factors including context, incoming social cues, and past experiences. Mouse models allow researchers to examine, in detail and at a cellular level, the brain function needed for these intricate social interactions. Initial studies have focused on males, and there is very little work examining dominance behaviours in females. With this research program, we will better understand how the brain initiates and responds to assuming a dominant or subordinate role within a competitive encounter in females, as well as in males. This is key to understanding how social experiences shape future behaviour. Because social behaviours are responsive to past experiences, they provide an exciting avenue to examine the interaction between an individual and its environment. In addition to normal peer-to-peer interactions, our research program studies how exposure to non-social stressors act more broadly to impact later peer-to-peer behaviours. In particular, we focus on the impact of stress when experienced during adolescence, a critical period for brain development. Our previous published work demonstrated that exposing adolescent mice to repeated predator stress during the post-pubertal period increases exploration of an unfamiliar peer in male mice, but decreases investigation of the odour of unfamiliar peers in female mice. These disparate results will be studied to better understand how social function in adults is differentially impacted by stressful experiences during adolescence in males and females. We will additionally measure the brain activity of stressed mice while they are presented with social odorant stimuli to gain insight into how social processing is changed in developmentally-stressed mice, and how it could be contributing to their behaviours. Lastly, we will describe the effects of adolescent stress on the activation of a protein, histone deacetylase 2 (HDAC2), in adult brain. Altered HDAC2 activation would have broader implications for brain function because this protein contributes to the regulation of a large number of genes important for the brain's ability to respond to experience. Findings from this research program will provide novel insights towards understanding the neural bases for social behaviours in males and females. These questions are fundamental to our understanding of how the brain receives, processes, and responds to social stimuli.