The long-term objective of the proposed research is to understand the rules by which visual neurons establish and maintain connections during development. Knowledge of these rules provides a foundation on which to study a broad range of neurological disorders and may have implications for the treatment of childhood amblyopia. Hypotheses will be tested regarding the neural mechanisms that give rise to synaptic competition in animal models of monocular deprivation (MD). These tests require detailed measurements of the time course of physiological changes induced by MD. Non-invasive functional magnetic resonance imaging (fMRI) will be used to obtain these measurements. The specific aims are: 1) to develop fMRI as a tool to rapidly assess the physiological effects of MD, 2) to compare the time courses of monocular and binocular recovery after MD, and 3) to quantify the effect of uncorrelated neural activity on the rate of ocular dominance plasticity. Kittens will be reared under conditions of normal visual experience, and/or MD. In the third aim, goggles constructed from miniature liquid crystal displays will be used to vary the level of uncorrelated activity in the deprived eye. Healthy brain function requires that neurons establish, strengthen and maintain proper connections during development. Sometimes these connections fail to develop normally or become damaged later in life, resulting in sensory or mental deficits. Our research aims to understanding the rules by which neurons form connections which may lead to more effective treatments for these conditions. [unreadable] [unreadable] [unreadable]