We are currently engaged in a program of research in our lab designed to examine the impact of peers on the neural underpinnings of risk-taking. Building on experimental work showing age differences in the degree to which peer presence evokes risky behavior (Gardner & Steinberg, 2005), with peers affecting risk-taking among adolescents but not adults, we have attempted to bring peer context into the scanner (Chein et al., 2009). Using an event-related fMRI design, we are examining age differences in neural activation at the moment of decision-making in different risk-taking tasks. To manipulate peer context, we measure task-related neural activation for each participant during two separate sessions. In one session, the participant completes the tasks while their peers are observing their performance from the scanner control room; in the other session, the participant completes the task with no observation. In each case, the participant is made aware of the condition. Consistent with our predictions, preliminary data indicates that adolescents activate socio-emotional reward regions (e.g., medial PFC, ventral striatum) more strongly when making risky decisions while being observed by their peers
