Mother Brain is Wired for Social Moments

Reorganization of the maternal brain, primed by oxytocin surge during childbirth, triggers the species-typical maternal social behavior. These brief social moments carry profound effects on the infants social brain and likely have a distinct signature in the maternal brain. Utilizing a double-blind, oxytocin/placebo administration crossover design, we imaged mothers twice while observing three naturalistic maternal-infant contexts in the home ecology; "unavailable", "unresponsive", and "social", when mothers engaged in synchronous pick-a-boo play. We found four processes by which mothers brain registers social moments. Salience - social moments increased activations throughout the maternal brain network; Brain-behavior coupling - caregiving behavior linked with socially-driven neural response; Oxytocin sensitivity - administration impacted neural response mainly to the social context; and Temporal engrams-consistent temporal patterns in insula and TP characterized response to social play. Findings describe how mothers brain compiles and amplifies these precious social moments to generate dyad-specific brain-behavior patterns that initiate the cross-generational transmission of human sociality.