Neural geometric representations of social memory for multi-individuals in medial prefrontal cortex

Abstract

Social memory, an ability to recognize acquainted individuals and related experience, is mainly stored in the medial prefrontal cortex (mPFC). However, it remains unknown how the mPFC encodes the memory of interacted multi-individuals. We, here, report that tuned low-dimensional, geometric subspaces in population neural activity of mPFC neurons encode this form of social memory. Different social experience, in which mice encounter four conspecifics associated with reward, aversive or neutral stimulus, respectively, substantially enhances segregation among identity-specific neural geometric subspaces. Progressive recruitments of mPFC neurons conjunctively encoding social identity and associated social valences underlie the enhanced neural representations of different individuals. Thus, our findings elucidate that tuned neural subspaces in mPFC population activities stably encode and maintain the memory of acquired multi-individuals over experience.