Self‐ and co‐regulation of physiological activity during mother‐daughter interactions: The role of adolescent non‐suicidal self‐injury

Background Non‐suicidal self‐injury (NSSI) is a significant public health concern that is thought to increase risk for future self‐injurious behaviors, including suicide attempts. Notably, NSSI is especially prevalent among adolescents, which underscores a critical need to identify modifiable risk factors that could be targeted to reduce future risk. The current study examined self‐ and co‐regulation of physiological responses during mother‐daughter interactions in adolescent girls with and without a history of NSSI. Methods Participants were 60 girls aged 13–17 with ( n = 27) and without ( n = 33) a history of NSSI and their mothers. Adolescents and their mothers completed positive and negative interaction tasks during which physiological reactivity was assessed via respiratory sinus arrhythmia (RSA). Results Using Actor‐Partner Interdependence Modeling (APIM), we found that adolescents with an NSSI history demonstrated a higher RSA setpoint than adolescents without this history during the negative, but not positive, interaction task. In addition, there were differences in co‐regulation during the negatively valenced interaction, such that mothers of daughters with NSSI were more reactive to fluctuations in their daughters' RSA than mothers of daughters without an NSSI history. Conclusions These findings highlight intra‐ and interpersonal aspects of physiological dysregulation associated with NSSI that could provide promising targets of intervention to reduce future risk in adolescent girls.