Maternal experience refines brain-wide neural networks for processing infant cries, facilitated by oxytocin

Infant distress vocalizations, such as pup calls in mice, are crucial signals for eliciting parental care. Previous research highlighted experience-dependent plasticity in the left primary auditory cortex, with oxytocin playing a facilitating role in enhancing neural and behavioral responses to these calls. However, the extent to which maternal experience reorganizes pup call processing across the entire brain, beyond just auditory regions, and the broader involvement of oxytocin in these brain-wide changes, remained largely unexplored. Understanding these mechanisms is vital for comprehending the neural underpinnings of adaptive caregiving.

Researchers investigated how innate and learned maternal experience shapes pup call-evoked behavior and brain-wide neural responses in mice. The study compared three groups: naive virgins, experienced virgins, and mothers. They employed a multi-modal approach, combining behavioral assays to quantify responses to pup calls, whole-brain activity mapping to visualize neural engagement across different brain regions, and specific analyses of oxytocinergic projections to identify circuits involved. The primary endpoint was the characterization of distinct large-scale neural networks recruited by pup calls across the different maternal experience states.

Pup calls recruit distinct large-scale neural networks in naive virgins, experienced virgins, and mothers, demonstrating a profound impact of maternal experience. With increasing maternal experience, the study observed a distributed pup call response network that became sparser yet more strongly coactivated. This pattern is consistent with a more efficient and specialized neural representation of infant cues, suggesting an optimization of brain resources for caregiving. Researchers identified an oxytocin-dense circuit that exhibited an experience-dependent pup call response pattern. This finding strongly suggests that oxytocin facilitates the experience-dependent refinement of the brain-wide response to pup calls.

Maternal experience refines brain-wide sensory processing to support adaptive caregiving behavior, with oxytocin playing a key facilitative role in this neural reorganization.