Development and function of higher visual areas in mice

? DESCRIPTION (provided by applicant): Higher visual functions, including object recognition and global motion detection, are carried out by extrastriate visual areas, or higher visual areas (HVAs), downstream from primary visual cortex. These higher processing functions often fail to completely recover following congenital blindness or amblyopia. These observations suggest that early visual experience sculpts HVA circuitry, but this has not been determined. To address this gap in knowledge, we propose an integrative approach using genetically engineered mice. Our goal is to determine how experience sculpts the normal development of HVA circuitry and how circuit deficits are caused by visual deprivation. Our preliminary data indicates that a subset of HVAs is slow to develop after eye opening, and fails to completely recover visual responses following dark rearing. By contrast, a complementary set of HVAs is visually responsive at eye opening, and fully recovers following dark rearing. We will map the development of HVAs at multiple time points, starting at eye opening, using intrinsic signal optical imaging and two photon calcium imaging. We will use a paradigm we developed for high resolution receptive field mapping of local populations of neurons in parallel. We will use technology we have recently developed to examine activity correlations between visual cortical areas and map how these change in development. We will dark rear mice to determine the effect of visual deprivation on HVA circuitry. The results from this project will reveal the role of visual experience in sculpting HVA selectivity and circuit development.