Neurodevelopmental changes in social and adaptive risk taking in adolescence

Adolescents’ risky behaviors are social in that they often have consequences on other people and are also adaptive in that they are sensitive to the potential reward outcome. However, little is known about how adolescents take adaptive risks that impact others, specifically in terms of how these risky behaviors change over the course of adolescence and how the developing brain supports this behavior. This integrative dissertation sought to investigate individual differences in the development of adaptive risky behaviors that affect adolescents’ best friend and parent. Study 1 shows that adolescents do not take adaptive risks differentially for their best friend and parent over time. Study 2 suggests that adolescents’ ever-changing peer landscape matters, since younger adolescents with consistent best friend (as their previous participation) took more adaptive risks for their best friend than those with inconsistent best friend, but older adolescents with inconsistent best friend took more adaptive risks than those with consistent best friend. Study 3 indicates that the “self” serves as an important foundation for promoting social behaviors, since functional connectivity during adaptive risk taking for oneself predicted behavioral adaptive risk taking for their parent, with this cross-context brain-behavior relation shifting over time. Collectively, these three studies also shed light on the social brain network (e.g., medial prefrontal cortex) for supporting adaptive vicarious risks. Taken together, this integrative dissertation demonstrates that both the self and the environment have implications for how adolescents make decisions involving others and therefore, optimally interact with others.Doctor of Philosoph