Parent-Child Dyads with Greater Parenting Stress Exhibit Enhanced Inter-Brain Synchrony During Shared Play
Abstract Parent-child dyads who are mutually attuned to each other during social interactions display interpersonal synchrony that can be observed overtly, in the form of joint behaviours, and biologically, such as through the temporal coordination of brain signals called inter-brain synchrony. Joint play provides ample opportunities for parent-child dyads to engage in matching interactions which not just facilitate the formation of bonds but also alleviate parenting stress in caregivers. Despite the beneficial effects of play on parents and the parent-child relationship, no study has investigated the dyadic neural mechanism by which this occurs. The present functional Near-infrared Spectroscopy (fNIRS) study aimed to examine the association between parenting stress and inter-brain synchrony in the prefrontal cortex of 31 mother-child and 29 father-child dyads while they engaged in shared play for 10 minutes. Shared play was miro-analytically coded into joint (i.e., in-phase matching of dyadic behaviours) and non-joint (i.e., no matching of dyadic behaviours) segments. Inter-brain synchrony was computed using cross-correlations over 15 s, 20 s, 25 s, 30 s and 35 s fixed-length windows of joint and non-joint play segments. Analyses of Covariance revealed that dyads with more parenting stress exhibited greater inter-brain synchrony in the frontal left cluster of the prefrontal cortex, but only for the 35 s fixed-length window. This finding suggests that continuous and positive instances of joint play may disproportionately benefit dyads who reported greater parenting stress, entraining underlying brain activation patterns involved in social cognition. Mother-child dyads also showed greater inter-brain synchrony than father-child dyads, alluding to possible gender differences in the effect of play on dyads. Findings present evidence of a potential dyadic neural pathway by which play benefits the parent-child relationship.