Changes in the adolescent brain and aggressive and risk-taking behaviours

Recent advances in neuroimaging techniques have contributed to a better understanding of brain development during adolescence, promoting a new approach to the study of adolescent problem behaviours, such as antisocial and risk-taking behaviours. Studies using functional magnetic resonance imaging have reported important structural changes in the adolescent brain, mainly affecting the prefrontal cortex-an area involved in cognitive and regulatory processes. Other important changes affect the basic threat system and reward system. Empirical evidence indicates that these two brain circuits present greater activity during adolescence than in adulthood. Thus, it is possible that reactive aggression and risk-taking behaviours are elicited by an imbalance between a still immature prefrontal cortex and two hiperresponsive brain systems. Some data indicate that changes in reward and basic threat circuits could be influenced by hormonal activity during puberty. This makes early adolescence a period of high vulnerability for problem behaviours related to lack of self-regulation.