Chronotype-related differences in childhood and adolescent aggression and antisocial behavior--a review of the literature.

Eveningness has been found to negatively affect adolescents' sleep and daytime functioning. Furthermore, eveningness is associated with greater impulsivity than morningness. Externalizing behavior could be chronotype-related, implying that the alteration of the circadian rhythm itself is connected to aspects of emotion and emotion regulation. The present study investigated chronotype-related differences in emotional and behavioral problems, especially aggression and antisocial behavior in children and adolescents. We conducted a comprehensive search via web of knowledge (MEDLINE, web of science), EBSCO, Ovid, PubMed, Google Scholar and PsycINDEX using the keywords: chronotype, chronobiology, morningness, eveningness, owls and larks as well as diurnal preference to fully capture every aspect of chronotype. For aggression we used the search terms: aggression, anger, hostility, violence, anti-social behavior, conduct disorder, oppositional defiant disorder, delinquency, social adjustment and externalizing behavior. N = 13 studies were included concerning chronotype, childhood, adolescence and antisocial behavior. Results showed that children and adolescents being E-types were more affected by daytime impairments. Additionally, behavioral and emotional problems as aggression or antisocial behavior were more pronounced in E- than in M-types. Our findings support an association of eveningness and the impact of aggression on children and adolescents. Longitudinal investigations should be conducted in order to insure causality of the effects in question. In addition, the elevated vulnerability toward aggression in evening types demonstrates the need for prevention and intervention programs that educate youths in proper sleep hygiene and evoke an awareness of the consequences of a habitually diminished sleep quality.