Grant: Discovery Grants Program - Individual

New evidence suggests that a variety of psychiatric disorders may be caused by alterations in learning and memory systems. Abnormalities in these different learning and memory systems, dynamic interactions between them, and interactions between these systems and other brain areas might mediate both normal and abnormal manifestations of thought and behaviour. The current research proposal is directly interested in unraveling these complex brain processes by utilizing a breakthrough paradigm for assessing different types of memories acquired by different systems on the same task. The visual discrimination task provides the opportunity to assess dorsal striatum, hippocampus, and amygdala learning and memory functions during acquisition of the same task and reveals what appears to be a novel subclass of associations and potential interactions that can occur between these neural systems. The specific aims of this research program are threefold: 1) provide further evidence that the competitive interactions between these systems represent examples of a novel subclass of competitive interactions. This aim will be achieved by running retention and reversal experiments in which one of these neural structures will be damaged after acquisition of the task or a set of experiments using the post-training memory consolidation paradigm in which the hypothesized necessary versus incidental associations will be manipulated; 2) gain an understanding of the consequences of blocking NMDA plasticity in these systems at different times during training. We will assess the effects of post-training, localized NMDA (CPP) blockade during visual discrimination acquisition; 3) obtain information about the consequences of blocking new protein synthesis in these same systems at different times during training. This will be achieved by assessing the effects of post-training, localized new protein synthesis blockade (anisomycin) during visual discrimination acquisition. Taken together, these experiments will give us a window into the dynamic and interactive nature of these neural systems with each other and provide important information about plasticity mechanisms supporting these complex brain functions and the localization of these processes.