Neuroimaging of developmental psychopathologies: the importance of self-regulatory and neuroplastic processes in adolescence.

Normal brain maturational and developmental processes, together with plastic reorganization of the brain in response to experiential demands, contribute to the acquisition of improved capacities for self-regulation and impulse control during adolescence. The frontal lobe is a main focus for these developmental and plastic processes during the transition from adolescence into adulthood. Tourette syndrome (TS), defined as the chronic presence of motor and vocal tics, has been increasingly conceptualized as a disorder of impaired self-regulatory control. This disordered control is thought to give rise to semicompulsory urges to perform the movements that constitute simple tics, complex tics, or compulsions. Neuroimaging studies suggest that the expression of the genetic diathesis to TS is influenced by genetic and nongenetic factors affecting activity-dependent reorganization of neuroregulatory systems, thereby influencing the phenotype, illness severity, and adult outcome of tic disorders. Similar developmental processes during adolescence likely determine the phenotype and natural history of a broad range of other complex neuropsychiatric disorders of childhood onset, and they likely contribute to the acquisition of improved self-regulatory capacities that characterize normal adolescent development.