ABSTRACT
Research into adolescent problem behavior in general uses the two-dimensional model of psychopathology that distinguishes between internalizing and externalizing problems (Achenbach & Edelbrock, 1983). The internalizing dimension indicates a liability for mood disorders such as depression and anxiety, whereas the externalizing dimension indicates a liability for antisocial behavior such as aggression and delinquency, as well as substance use. Although general population studies into adolescent psychopathology had already been conducted in the 1960s, systematic longitudinal research emerged only in the 1980s (Verhulst, Koot, & Berden, 1990; Zoccolillo, 1992). Longitudinal research into adolescent aggression (Loeber, 1982; Olweus, 1979) and delinquency (Farrington, 2015) started earlier, as early as in the 1930s and 1940s, but also became much more common from the 1980s onward. The development of anxiety, depression, delinquency, aggression, and substance use are the core topics of this chapter. It presents empirical findings on mean-level change, developmental trajectories, and developmental trajectory chains. Is adolescence a a period of turmoil and chaos or the formative period in life? The findings of this chapter tend to support the formative period perspective. Most adolescents grow out of internalizing and externalizing problems in adolescence, thereby showing adaptive development. Especially externalizing problems seem to refer to temporary turmoil that has become more and more visible because of the prolongation of adolescence.
