Our research centers on the capacity for reorganization in the central nervous system. Animals that sustain sudden injury to particular brain pathways can exhibit remarkable improvement in sensory and motor functions. Although the models of structural and chemical reorganization in the brain-damaged animals provided new insight into the remarkable diversity of neuronal mechanisms that permit restoration of function, human neurodegenerative disorders (especially those associated with aging such as Parkinson's and Alzheimer's diseases) are insidious in onset. Two major forefronts of research are to identify the processes that dispose certain neurons to degenerate in these diseases and to determine means by which the brain's compensatory mechanisms may be induced to retard slow degenerative processes or to counteract their functional consequences.