ABSTRACT
The etiology of externalizing problem behaviors has been a fundamental concern for researchers and professionals dealing with externalizing problems. Biosocial theory asserts that both nature and nurture, as well as their interaction, are important factors in influencing a variety of behaviors, including externalizing behaviors. Children, adolescents, and adults with externalizing problems represent an extremely heterogeneous group. A number of different terms are used to describe externalizing behaviors in the literature, including antisocial behavior, aggression, disruptive behaviors, and conduct problems. The focus in the externalizing literature was shifted from the behavior itself to the onset of the behavior when the distinction was made between childhood-onset and adolescent-onset conduct problems. Twin and adoption studies of externalizing behaviors routinely demonstrate genetic influences on these behaviors, regardless of which externalizing behaviors are studied. In the diathesis-stress model, certain predispositions increase a person’s risk of experiencing poor outcomes or developing a psychological disorder when they encounter a negative environment.
