The interaction of psychosocial adversity and biological risk in childhood aggression

Childhood aggression has both biological and environmental underpinnings. However, the manner in which these factors interact to influence various types of aggression remains an important area of study. The current study examined the degree to which biological risk and psychosocial adversity, both alone and in combination, are associated with childhood aggression. Linear regression procedures were used to assess the extent to which biological risk status (low vs. high serotonergic responsivity, as measured by prolactin response to fenfluramine), magnitude of psychosocial risk, and the interaction of these factors predicted parent and teacher ratings of aggression and delinquency. After accounting for the independent contribution of biological and psychosocial risk, the interaction of biological and psychosocial risk was significantly associated with parent-rated aggression and marginally related to parent-rated delinquency. In contrast, no such interaction was observed for teacher-rated aggression. Findings suggest that individuals at biological risk for aggression may be particularly vulnerable to the impact of psychosocial adversity.