Plasticity in the Auditory Cortex of Mothers

Cortical circuits remain challenging to study because neurons are heterogeneous and anatomically intertwined. In the primary auditory cortex (A1), for example, spiking responses to natural stimuli like vocalization cannot be easily predicted from their location or spectral responsivity; even neighboring neurons vary widely in their response profiles, let alone during different behavioral contexts. I will discuss recent results in our effort to study auditory plasticity in the context of mother-infant bonding, an interaction that rapidly develops following parturition. We studied how ultrasonic vocalizations (USVs) are represented in the brain of mothers, when they first start caring for their newborn pups. Using a combination of anatomical, chemogenetic, and electrophysiological techniques, we found a high-order cortical region - the temporal association cortex (TeA), which is associated with USV processing. Monosynaptic connections into TeA come from diverse input sources, both cortically and subcortically. Further, we identified a circuit connecting USV-responsive neurons from primary auditory cortex to TeA. Silencing USV-responsive neurons in the A1-TeA circuit impairs auditory-driven maternal choices towards pup calls, and mothers show a unique pattern of plasticity in TeA. TeA neurons become decorrelated in mothers, improving the detection of pup USVs in TeA. We thus suggest that TeA is a hub of plasticity for auditory-driven social cues.