Parent-Child Autonomic Synchrony During Vicarious Extinction Learning in Pediatric PTSD

Children must learn basic functional processes directly from their caregivers and child psychopathology may disrupt this transmission. This transmission may be seen through biological measures like peripheral nervous system outputs like skin conductance (SCR). Fear learning deficits have been seen in affective disorders like PTSD and are useful for studying parent-child learning transmission. Our study uses a vicarious fear extinction paradigm to study if biological synchrony (SCR and heart rate variability (HRV)) are potential mechanisms in which children learn safety cues from their parents. There were 16 dyads (PTSD n=11, TD n=5) undergoing a vicarious fear extinction paradigm. We used cross-recurrence quantification analysis (CRQA) to assess SCR and HRV synchrony between parent-child dyads. We then used a linear model looking at group differences between PTSD dyads and typically developing (TD) dyads. For SCR, we saw a significant group difference (p=.037) indicating that TD dyads had higher SCR synchrony compared to PTSD dyads. For HRV, there were no group differences between PTSD and TD dyads (p=.325). These results suggest that SCR synchrony, but not HRV, may be a potential mechanism that allows for fear and safety learning in youth. While this is preliminary, it may give the first insights on how therapies such as Trauma-Focused Cognitive Behavioral Therapy critically rely on parental coaching to model appropriate fear responses to help their child to recover from trauma. ### Competing Interest Statement The authors have declared no competing interest.