Dynamic respiratory sinus arrhythmia self-regulation and coregulation in response to caregiving challenges in at-risk mother-child and father-child dyads.

We examined how mother-preschooler and father-preschooler dyads differed in dynamic self-regulation and time-lagged coregulation of respiratory sinus arrhythmia (RSA) when having to transition from play into a challenging disciplinary context, and how individual and dyadic regulatory responses to this challenge varied by parenting risk. Participants included 78 mother-preschooler and 51 father-preschooler dyads (53% female, 63.3% non-Hispanic White) oversampled for familial risk. At 2½ years, parents self-reported harsh parenting. At 3 years, parent-child RSA was collected during free play and cleanup tasks. Multilevel models of time-lagged RSA (i.e., parent RSA predicting child RSA in the next time unit and vice versa) were conducted. In response to a task with increased challenge and parenting demands, mothers and children showed expected individual RSA decreases (indicating active regulation), whereas fathers showed increases in RSA (suggesting decreasing arousal or disengagement). Mother-driven negative time-lagged RSA coregulation and father-driven positive time-lagged RSA coregulation were observed during play, but not during cleanup. Harsh parenting was associated with altered RSA responses to challenge: During cleanup, harsher mothers showed no active regulation, suggesting disengagement, harsher fathers showed more stability in RSA self-regulation, and child-driven negative RSA coregulation with harsher fathers was observed. Findings suggest that during preschool, (a) parents are the typical drivers of RSA coregulation, (b) challenging contexts and parenting risk alter dynamic RSA self-regulation and time-lagged RSA coregulation, and (c) typical and atypical RSA self-regulation and time-lagged coregulation patterns differ between mother-child and father-child dyads. (PsycInfo Database Record (c) 2025 APA, all rights reserved).