The mere copresence of another person synchronizes physiological signals, but no study has systematically investigated the effects of the type of emotional state and the type of relationship in eliciting dyadic physiological synchrony. In this study, we investigated the synchrony of pairs of strangers, companions, and romantic partners while watching a series of video clips designed to elicit different emotions. Maximal cross-correlation of heart rate variability (HRV) was used to quantify dyadic synchrony. The findings suggest that an existing social relationship might reduce the predisposition to conform one’s autonomic responses to a friend or romantic partner during social situations that do not require direct interaction.

Inter-subject synchronization reflects the entrainment of two individuals to each other’s brain signals. In parent-child dyads, synchronization indicates an attunement to each other’s emotional states. Despite the ubiquity with which parents and their children watch screen media together, no study has investigated synchronization in father-child dyads during co-viewing. The present study examined whether father-child dyads would exhibit inter-subject synchronization that is unique to the dyad and hence would not be observed in control dyads (i.e., randomly paired signals). Hyperscanning fNIRS was used to record the prefrontal cortex (PFC) signals of 29 fathers and their preschool-aged children as they co-viewed children’s shows. Three 1-min videos from “Brave”, “Peppa Pig” and “The Incredibles” were presented to each dyad and children’s ratings of video positivity and familiarity were obtained. Four PFC clusters were analyzed: medial left, medial right, frontal left and frontal right clusters. Results demonstrated that true father-child dyads showed significantly greater synchronization than control dyads in the medial left cluster during the emotionally arousing conflict scene. Dyads with older fathers displayed less synchrony and older fathers, compared to younger ones, exhibited greater activity. These findings suggest unique inter-subject synchronization in father-child dyads during co-viewing which is potentially modulated by parental age.

Parent-child dyads who are mutually attuned to each other during social interactions display interpersonal synchrony that can be observed behaviourally and through the temporal coordination of brain signals called inter-brain synchrony. Parenting stress undermines the quality of parent-child interactions. However, no study has examined synchrony in relation to parenting stress during everyday shared play. The present fNIRS study examined the association between parenting stress and inter-brain synchrony in the prefrontal cortex (PFC) of 31 mother-child and 29 father-child dyads while they engaged in shared play for 10 minutes. Shared play was micro-analytically coded into joint and non-joint segments. Inter-brain synchrony was computed using cross-correlations over 15 s, 20 s, 25 s, 30 s and 35 s fixed-length windows. Findings showed that stressed dyads exhibited less synchrony in the posterior right cluster of the PFC during joint segments of play, and, contrary to expectations, stressed dyads also showed greater synchrony in the frontal left cluster. These findings suggest that dyads with more parenting stress experienced less similarities in brain areas involved in emotional processing and regulation, whilst simultaneously requiring greater neural entrainment in brain areas that support task management and social-behavioural organisation in order to sustain prolonged periods of joint interactions.

Savouring is an emotion regulation strategy and intervention that focuses on the process of attending, intensifying and prolonging positive experiences and positive affect associated with these memories. Personal savouring involves a reflection on positive memories that are specific to the individual and do not involve others. In contrast, relational savouring entails reflecting on instances when people were responsive to the needs of their significant others. Such interventions hold potential benefits in enhancing positive affect (PA) and reducing negative affect (NA) for both parents of children with autism spectrum disorder (ASD) and parents of neurotypical children. Adults with greater symptoms of generalised anxiety have been found to have less PA and more NA. However, no study has investigated the effects of a mother’s anxiety symptoms on the efficacy of savouring in enhancing PA and reducing NA. Thus, this paper combined personal and relational savouring to investigate whether savouring may enhance PA and reduce NA of a pooled sample of mothers of neurotypical children and mothers of children with ASD. 52 mothers of neurotypical children and 26 mothers of children with ASD aged 3–7 years old were given a series of questionnaires and randomly assigned to either relational savouring or personal savouring conditions. In relational savouring, mothers were asked to reflect upon a shared positive experience with their child while in the personal savouring condition, a personal positive experience was recalled. Across mothers of children with ASD and neurotypical children, findings suggest that savouring leads to a decrease in NA (p < 0.01) but not increases in PA. Similarly, mothers with higher levels of anxiety experience a greater decrease in NA (p < 0.001) compared to mothers with lower levels of anxiety post-savouring. This study proposes that a brief savouring intervention may be effective among mothers of preschoolers. As lower levels of negative affect is linked to healthier psychological well-being, mothers might be able to engage in more effective and warm parenting after savouring exercises, which would cultivate positive mother-child relationships that benefit their children in the long-term.