Neural Mapping of the Social Landscape

项目总结

PROJECT SUMMARY Psychiatric disorders that feature social impairment (e.g., Autism Spectrum Disorder) pose a significant health burden in the United States. Attempts to understand the underlying neurobiology of such social impairments have largely focused on classical `social brain' networks that include regions such as the medial prefrontal cortex. However, these disorders also tend to show hippocampal dysfunction – a region not normally included in descriptions of social brain networks. This prompts the question: are social and hippocampal dysfunction linked? Social cognitive mapping, whereby social information is organized and stored in the hippocampal formation to inform flexible social decision-making, is one candidate mechanism that may unify these seemingly distinct observations. In this proposal, we will use a naturalistic choose-your-own-adventure task that probes social cognitive mapping processes. Dimensions of social power and affiliation define a `social space' within which other people are coordinates and evolving relationships are trajectories. Previous work in our lab showed that hippocampus and posterior cingulate cortex activity tracked trajectories within this space. Furthermore, the parameter estimates from the hippocampus related to self-reported social function, suggesting that this neural tracking is relevant to real-world social cognition and behavior. To characterize the role of social cognitive mapping in both normal and abnormal social cognition, this proposal will use a large, multidimensional dataset, and cutting-edge approaches to functional magnetic resonance imaging (fMRI). First, we will leverage data-driven methods on a large and diverse online sample to relate the geometry of behavior within this two-dimensional social space to the underlying structure of social dysfunction. Second, we will use ultra-high field (7T) fMRI and state-of-the-art analyses to test for specific neural signatures within the social space that are predicted by the social cognitive mapping perspective (e.g., a grid-like representation). These results will further the fields of social cognitive and computational neuroscience, by revealing the behavioral and neural correlates of evolving relationships and how they relate to social function, and by extending hippocampal function to abstract, non-spatial domains. Further, this approach will allow the role of cognitive mapping in social dysfunction to be explored, and may provide candidate therapeutic targets for psychiatric disorders.