RESUMO
This study examined autonomic nervous system activity (respiratory sinus arrhythmia [RSA]) as a biomarker of psychopathology in an ethnically and socioeconomically diverse sample (N = 57) of young children ages 4-7 years. RSA was measured at baseline and across four standardized tasks designed to assess self-regulation in both affective (i.e., "hot") and cognitive (i.e., "cool") contexts during early childhood. Our findings reveal that age moderated RSA activity, such that reduced RSA suppression was associated with a heightened risk of externalizing problems among older children during "cool" and "hot" contexts; for younger children, only RSA suppression during "hot" contexts predicted externalizing risk. The influence of socioeconomic disadvantage did not moderate the relationship between RSA and the risk of psychopathology, and there were minimal associations between RSA suppression and internalizing symptoms at this age range. These results suggest that autonomic variability may be a more effective predictor of psychopathology risk in older children, perhaps as they transition into formal schooling and face increasingly complex cognitive and social demands. Findings have implications for the identification of psychopathology in early developmental periods when regulation over emotions becomes essential for academic and social success.