Developmental changes in dopamine neurotransmission in adolescence: behavioral implications and issues in assessment.

Adolescence is characterized by increased risk-taking, novelty-seeking, and locomotor activity, all of which suggest a heightened appetitive drive. The neurotransmitter dopamine is typically associated with behavioral activation and heightened forms of appetitive behavior in mammalian species, and this pattern of activation has been described in terms of a neurobehavioral system that underlies incentive-motivated behavior. Adolescence may be a time of elevated activity within this system. This review provides a summary of changes within cortical and subcortical dopaminergic systems that may account for changes in cognition and affect that characterize adolescent behavior. Because there is a dearth of information regarding neurochemical changes in human adolescents, models for assessing links between neurochemical activity and behavior in human adolescents will be described using molecular genetic techniques. Furthermore, we will suggest how these techniques can be combined with other methods such as pharmacology to measure the impact of dopamine activity on behavior and how this relation changes through the lifespan.