We’ve all seen it: moms and dads cradling their infants, cooing, smiling, widening their eyes, in a preverbal dance of expression and movement as parent and child each anticipate the other’s response, creating the life-affirming parent-child bond.

It’s an interaction known in child-development circles as “synchrony.” Northeastern psychology professor Lisa Feldman Barrett and her colleagues at Massachusetts General Hospital set out to uncover its neurobiological underpinnings. In new research published the journal Proceedings of the National Academy of Sciences, they found, for the first time, that the neurotransmitter dopamine is involved in human bonding, bringing the brain’s reward system into our understanding of how we form human attachments.

Link to full Northeastern Univ. release