Maternal Chemical Signals Enhance Brain-to-Brain Synchronization in Infants and Adults

December 10, 2021 - Volume 7, Issue 50 - DOI: 10.1126/sciadv.abg6867

Commentary

A mother's body odor serves as an important safety-promoting and social-awareness signal for her baby, but their role in human brain maturation is largely unknown.

This study used an ecological paradigm and duplex EEG recordings to investigate the effects of maternal chemical signals on brain-to-brain synchronization during infant-mother and infant-stranger interactions, with and without maternal body odor.

The results showed that neural connections of right-to-right brain-theta synchrony appeared across conditions and sensitized important nodes of the social brain in maturing infants. And infant-mother interactions were inducing greater brain-to-brain synchronization.

However, the researchers found that maternal chemical signals weakened this difference. Infants showed more social attention, positive arousal, and safety/approach behavior in the maternal chemosignal state.

This has been found to enhance neural synchronization between infants and strangers. Human mothers use inter-brain mechanisms to regulate their infants' social brains, and chemical signals may maintain the infant's social transition from mother-infant bonding to living in a social group, the study said.