PROJECT SUMMARY
Most mammals, including humans, navigate a life motivated and shaped by a drive to seek rewards such as
food, water, and social interactions. Social stimuli can act as positive reinforcers, driving animals to pursue and
interact with other members of their own species (e.g., people regularly hanging out with friends or a mouse
repeatedly visiting to investigate a novel conspecific). Significantly, deficits in motivation to seek socially
rewarding stimuli and deficits in social reward processing are associated with several disorders, such as Autism
Spectrum Disorders. While the neural substrates underlying non-social reward-related behaviors (e.g., food
rewards) have been studied extensively, similar studies have been more difficult for social rewards because of
the inherent complexity of social interactions. It is unclear if there are differences in how the brain processes
social versus non-social rewards. Additionally, although intranasal oxytocin delivery alleviates social motivation
deficits in human subjects with autism, how oxytocin modulates neural circuits mediating social reward-related
behaviors remains poorly understood. Therefore, addressing these questions will have immense consequences
for human health.
We hope to address these gaps in knowledge by combining cellular resolution imaging techniques and
optogenetics with a novel operant behavioral paradigm to thoroughly and systematically map how social and
non-social rewards are represented in the medial prefrontal cortex (AIM 1a). We will determine if the mPFC
reward representations are modulated by the internal state of the animal. (AIM 1b). We will evaluate how oxytocin
inputs modulate social and non-social reward representations in the mPFC by imaging the activity of mPFC
neurons while silencing oxytocin inputs to the mPFC (AIM 2). Finally, we will determine if social reward
representations such as proximity of social reward, valence, and reward prediction error are functionally
clustered in mPFC projection populations (AIM 3). In summary, this research will help us identify differences and
similarities in how the brain encodes social rewards versus non-social rewards and how the animal's internal
state modulates these representations. Additionally, given the promising therapeutic possibility of using
intranasal oxytocin administration to children and adults with autism, elucidation of the role of the oxytocin on
mPFC function will be a valuable addition to the autism research community.