Adolescence and externalizing problem behavior: The role of (co-)parenting and the stress response system

The present PhD dissertation studied the associations between (co-)parenting, the stress response system (i.e., cortisol stress response, methylation levels of NR3C1) and externalizing problem behavior in adolescence. The ecological model of coparenting (Feinberg, 2003) and the Adaptive Calibration Model of stress responsivity (Del Giudice et al., 2011) served as theoretical frameworks.

Data from two large longitudinal projects were used in the current PhD dissertation: STRATEGIES (i.e., Studying Transactions in Adolescence: Testing Genes in Interaction With Environments) and, MIND (i.e., Methylation in Development). In the STRATEGIES study 1116 adolescents, 747 mothers and 645 fathers in wave 1. In the MIND study 596 adolescents, 414 mothers and 306 fathers participated in wave 1.

The first study classified parents into parenting styles based on parenting dimensions reported by adolescents, for three waves with one-year interval. Classification was based on a relatively new statistical method, namely subspace k-means clustering. We found evidence for two parenting styles: authoritative and authoritarian parenting style. Change from authoritative to authoritarian parenting style over time was associated with a lower adolescent self-concept and an increase in externalizing problem behavior, whereas change from authoritarian to authoritative parenting style was associated with a higher self-concept and a decrease in externalizing problem behavior.

The second study investigated the mediating role of parenting in the association between coparenting and externalizing problems in adolescence. Structural equation models found that a better coparenting relation was associated with less adolescent externalizing problem behavior. For both mothers and fathers this association was mediated by psychological control. For fathers, the association was also mediated by physical punishment.

In the third study the moderating role of cortisol stress response was studied in the association between parenting and externalizing problem behavior. Hierarchical multiple regression analysis showed that both cortisol peak and cortisol stress reactivity were significant moderators in the association between certain parenting dimensions (i.e., support and psychological control) and externalizing problem behavior.

The fourth study explored the association between parenting (i.e., parenting dimensions and styles) and externalizing behavior in adolescence and whether methylation on NR3C1 is a moderator in this association. NR3C1 methylation moderated the association between physical punishment and externalizing problem behavior, measured concurrently.

To conclude, the current PhD dissertation indicates that the stress response system is an important moderator in the association between parenting and externalizing problem behavior and that parenting is important to understand the association between coparenting and externalizing problem behavior.