PROJECT SUMMARY/ABSTRACT
Most existing work on adolescent development has focused on risk and psychopathology, as opposed to
more positive developments, such as prosocial behavior. This previous focus is unfortunate given that
prosocial behavior has been linked with a variety of positive health outcomes across a wide age range,
including in childhood and adolescence. Given these observed health benefits of prosocial behavior, an
increased focus on the neurobehavioral developments that underlie prosocial behavior during adolescence is
warranted. The proposed work will examine developmental differences in prosocial behavior, specifically
examining underlying neural mechanisms of prosocial behavior that may contribute to observed health
outcomes. This will be done by linking neurobehavioral correlates of prosocial behavior with interferon-gamma
(IFN-g), an important marker of antiviral immunity.
The objective of this NRSA application is to foster my development as a social neuroscientist investigating
the impact of social phenomena on health across development. To do so, the proposed study will 1) examine
developmental differences in prosocial behavior, 2) characterize the neural underpinnings of prosocial
behavior, and 3) examine associations between IFN-g and prosocial behavior across development. Prosocial
behavior will be examined via reinforcement learning models, which can provide a measure of motivation or
intention to act prosocially. Participants (ntotal=120; children [9-10 yr], adolescents [14-15 yr], young adults [19-
20 yr]) will complete a probabilistic learning task in which they learn contingencies via positive and negative
reinforcement in order to earn money for themselves (self learning) and a friend (prosocial learning), while
undergoing a functional magnetic resonance imaging (fMRI) scan. A subset of subjects will complete a blood
draw to assess IFN-g.
Increased reward sensitivity, which is associated with greater adolescent well-being, has been shown to
facilitate reinforcement learning generally. Thus, adolescent reward sensitivity may promote prosocial
learning—learning in order to benefit someone else. It is therefore predicted that 1) adolescents will have
better prosocial learning rates relative to adolescents’ self learning rates and relative to children/young adults’
prosocial learning rates. Additionally, given the proposed reward-based mechanism of prosocial learning, it is
hypothesized that 2) increased striatal activity will mediate the predicted developmental differences in prosocial
learning rates, such that adolescents will have the best prosocial learning rates due to increased prediction
error-related striatal activity. Finally, it is predicted that 3) higher IFN-g will be associated with better prosocial
learning and greater prediction error-related striatal activity during prosocial learning. The present study will
help to elucidate underlying neural and immunological correlates of prosocial behavior across development,
leading to a better understanding of observed health benefits and their developmental trajectory.
