Abstract
The dorsal hippocampal CA1 (dCA1) is a key regulator of stress adaptation. Our previous work demonstrated that dCA1 neuronal ensembles and stress engrams contribute to resilience and susceptibility to social stress. Here, we show that dCA1 also plays a critical role in sex differences in social valence processing. Using behavioural paradigms involving positive and negative social experiences, we found that male mice recognized conspecific identity regardless of valence, whereas female mice showed impaired identity recognition following negative social experiences. In vivo calcium imaging revealed reduced dCA1 representations of social information in females during negative social valence processing. Enhancing dCA1 activity rescued this deficit, restoring social identity recognition in female mice. Together, these findings suggest that dCA1 integrates social memory and emotional valence to shape adaptive behavioural responses. This framework may help explain sex differences in vulnerability to social stress-related mood disorders and identify hippocampal mechanisms that promote resilience.
Biography
Tak Pan Wong is an Associate Professor in the Department of Psychiatry at McGill University. He completed his PhD in Neuropharmacology at McGill and postdoctoral training at the University of British Columbia, where he studied NMDA receptors and hippocampal synaptic plasticity. His laboratory investigates hippocampal mechanisms of vulnerability and resilience to stress-related mood disorders, including how NMDA receptor function, memory engrams and social representations in the hippocampus shape susceptibility to social stress. His current work examines how the hippocampus integrates social memory and emotional valence, and how this differs between sexes.