Adolescence is a developmental period characterized by an orientation towards excitement and arousal, emotionally driven behaviors, and heightened sensitivity to rewards. Recent evidence from developmental neuroscience studies has shown significant changes in dopaminergic reward processing during adolescence. The prevailing view in the field of adolescent brain development is that this heightened activity in the reward system (e.g., adolescent peaks in ventral striatum activation) serves as a liability, orienting adolescents towards risky behaviors, increasing their sensitivity to social evaluation and loss, and resulting in compromised well-being. Such a deficit perspective driven by biologically determined brain immaturities implies a ubiquitous, inevitability to adolescent risk taking that constrains our ability to intervene.
Dr. Telzer has proposed a new conceptualization and adaptive role of adolescent reward sensitivity, such that ventral striatum reactivity can actually lead adolescents away from risks (see Telzer 2016, Developmental Cognitive Neuroscience). Rather than promoting risk taking, recent evidence from Dr. Telzer’s lab reveals that heightened striatal reactivity may actually motivate adolescents to engage in more thoughtful behaviors, facilitating improved cognition, and ultimately protecting them from developing depression and engaging in risk-taking behavior.
In one set of studies, Dr. Telzer examined neural responses to prosocial decision making in adolescence. Engagement in prosocial behaviors activates high intensity, rewarding feelings that engage the reward system. Results indicated that adolescents who showed heightened activation in the ventral striatum when making prosocial decisions showed longitudinal declines in risk taking behaviors (e.g., stealing, drinking alcohol, using drugs, and skipping school) and depressive symptoms over the following year (Telzer et al., 2013, Developmental Cognitive Neuroscience; Telzer et al., 2014, PNAS). This was the first study to show that the ventral striatum, the very same neural region thought to confer risk for maladaptive behaviors, is also a protective neural signal against these same behaviors.
In another study, Dr. Telzer examined how maternal presence changes the way adolescents perceive risks. During an fMRI scan, adolescents completed a risk taking task (a driving simulation) alone and in the presence of their mother. Adolescents made significantly more risky decisions when alone (55% of decisions) than when their mother was present (45% of decisions). Importantly, when adolescents made safe decisions, they showed significant functional coupling (i.e., cross-talk between neural regions) between the ventral striatum and the ventrolateral prefrontal cortex (VLPFC) when their mothers were present (Telzer et al., 2015, Social Cognitive Affective Neuroscience). In other words, making safe decisions in the presence of their mother may elicit a reward response that promotes activation of the prefrontal cortex, a key brain region involved in cognitive control. Theories of adolescent risk-taking propose that heightened ventral striatum sensitivity largely underlies risk-taking during adolescence. Importantly, this study shows that the ventral striatum can be redirected away from risky decisions and towards more deliberative and safe decisions when mothers are present.
With funding from the National Institutes of Health and National Science Foundation, Dr. Telzer’s lab will be conducting a 5-year longitudinal study to continue to examine brain development in adolescence in order to carefully unpack the social contexts that promote or hinder positive developmental outcomes.
Dr. Telzer is an Associate Professor in the Developmental Psychology Program within the Department of Psychology and Neuroscience at UNC Chapel Hill. She seeks to understand the neural changes that support social, emotional, and cognitive development from childhood to adulthood. Dr. Telzer’ goal is to understand how the social world is processed in the developing brain to ultimately impact adolescents’ well-being, focusing on many outcomes, including psychological well-being, academic motivation, intergroup biases, and health compromising behaviors such as substance use.