Adolescent decision-making is a topic of great public and scientific interest. However, much of the neuroimaging research in this area contrasts only one facet of decision-making (e.g., neural responses to anticipation or receipt of monetary rewards). Few studies have directly examined the processes that occur immediately before making a decision between two options that have varied and unpredictable potential rewards and penalties. Understanding adolescent decision-making from this vantage point may prove critical to ameliorating risky behavior and improving developmental outcomes. In this study, participants aged 14–16 years engaged in a driving simulation game while undergoing fMRI. Results indicated activity in ventral striatum preceded risky decisions and activity in right inferior frontal gyrus (rIFG) preceded safe decisions. Furthermore, participants who reported higher sensation-seeking and sensitivity to reward and punishment demonstrated lower rIFG activity during safe decisions. Finally, over successive games, rIFG activity preceding risky decisions decreased, whereas thalamus and caudate activity increased during positive feedback (taking a risk without crashing). These results indicate that regions traditionally associated with reward processing and inhibition not only drive risky decision-making in the moment but also contribute to learning about risk tradeoffs during adolescence.

Previous neuroimaging research with adults suggests that the medial prefrontal cortex (MPFC) and the medial posterior parietal cortex (MPPC) are engaged during self-knowledge retrieval processes. However, this has yet to be assessed in a developmental sample. Twelve children and 12 adults (average age = 10.2 and 26.1 years, respectively) reported whether short phrases described themselves or a highly familiar other (Harry Potter) while undergoing functional magnetic resonance imaging. In both children and adults, the MPFC was relatively more active during self- than social knowledge retrieval, and the MPPC was relatively more active during social than self-knowledge retrieval. Direct comparisons between children and adults indicated that children activated the MPFC during self-knowledge retrieval to a much greater extent than adults. The particular regions of the MPPC involved varied between the two groups, with the posterior precuneus engaged by adults, but the anterior precuneus and posterior cingulate engaged by children. Only children activated the MPFC significantly above baseline during self-knowledge retrieval. Implications for social cognitive development and the processing functions performed by the MPFC are discussed.