UCLA

Adolescence is a developmental period characterized by increased risk-taking behavior. Current neurodevelopmental models of adolescent risky decision-making explain this behavior based on an imbalance in development of reward and regulatory regions in the brain. This has led many researchers to focus on the ontogeny of reward processing, finding adolescents to be behaviorally and neurally hypersensitive to rewards relative to adults. However, current research has not investigated adolescent sensitivity to potential losses, a fundamental component of many risky choices. In this dissertation, I use a multi-method program of research, including experimental tasks, surveys, functional magnetic resonance imaging (fMRI), and psychophysiology, to explore how the potential for both gains and losses contribute to adolescent risky decision-making. My research demonstrates that adolescents, like adults, are more sensitive to losses than to gains when deciding whether or not to accept a risk. However, adolescents recruit more cognitive resources than adults when choosing to avoid risk, suggesting that adult patterns of risk-avoidance become less effortful across development. Furthermore, adolescents are actually more neurobehaviorally sensitive to changes in value than adults are, suggesting that hypersensitivity to value may underlie observed sensitivity to reward in adolescents. Finally, I present evidence suggesting that higher baseline levels of a proxy for dopamine contribute to greater sensitivity to value during risky decision-making with the potential for loss. Taken together, these findings suggest the possibility of a role for dopamine in modulating the neural response to value (and not simply to reward) observed functionally in the ventral striatum, which in turn influences risk-taking behavior.