Neurobiology of adolescent substance use and addictive behaviors: treatment implications

Abstract

Psychoactive substance and nonsubstance/behavioral addictions are major public health concerns associated with significant societal cost. Adolescence is a period of dynamic biologic, psychological, and behavioral changes. Adolescence is also associated with an increased risk for substance use and addictive disorders. During adolescence, developmental changes in neural circuitry of reward processing, motivation, cognitive control, and stress may contribute to vulnerability for increased levels of engagement in substance use and nonsubstance addictive behaviors. Current biologic models of adolescent vulnerability for addictions incorporate existing data on allostatic changes in function and structure of the midbrain dopaminergic system, stress-associated neuroplasticity, and maturational imbalances between cognitive control and reward reactivity. When characterizing adolescent vulnerability, identifying subgroups of adolescents at high risk for addictive behaviors is a major goal of the addiction field. Genetics, epigenetics, and intermediate phenotypes/endophenotypes may assist in characterizing children and adolescents at risk. Improved understanding of the neurobiology of adolescence and addiction vulnerability has the potential to refine screening, enhance prevention and intervention strategies, and inform public policy.

Figure 1

Neurocircuitry schematic illustrating the combination of neuroadaptations in the brain circuitry for the three stages of the addiction cycle: 1) binge/intoxication; 2) withdrawal/negative affect; 3) preoccupation/anticipation ‘craving’. Figure reproduced with permission from Koob GF,Volkow ND. Neurocircuitry of Addiction. Neuropsychopharmacology (2010), 35, 217–238. Copyrighted ©2013, American College of Neuropsychopharmacology.

Figure 2

Dynamic sequence of Cortical Gray Matter (GM) Maturation from childhood through early adulthood from right lateral and top views. The sidebar shows a color representation in units of GM volume. Figure reproduced with permission from Gotay N et al. Dynamic mapping of human cortical development during childhood through early adulthood. Proceedings of the National Academy of Sciences (2004), 101(21), 8174–8179. Copyrighted © 2004, The National Academy of Sciences of the USA.