Parental and romantic attachment shape brain processing of infant cues.

Periods of bond formation are associated with evolutionary-adaptive reorganization of physiological and behavioral responses and increased attention to attachment-related cues. We measured event-related potential responses to infant stimuli among new parents, new lovers, and romantically unattached singles (N=65). For parents, infant stimuli included own and unfamiliar infant. Viewing unfamiliar infants, parents and lovers exhibited greater activation at 140-160 and 300-500 ms post-stimulus compared to singles at occipital-lateral (N170) and central-frontal (P3a) sites, indicating greater initial attention to infant cues. Parents exhibited lowest amplitudes in the parietal-distributed P300 component, implicated in controlled attention, towards the unfamiliar infant but greatest response to their own infant in the same waveform. These findings are the first to demonstrate that periods of bond formation activate brain reactivity to parenting-related cues. Parents' heightened response to own infant accords with evolutionary models underscoring the need to direct resources to the survival and well being of one's own offspring.