Role of the precentral cortex in adapting behavior to different mechanical environments

摘要: We routinely produce movements under different mechanical contexts. All interactions with the physical environment, such as swinging a hammer or lifting carton of milk, alter forces experienced during movement. With repeated experience, sensorimotor maps are adapted to maintain high level movement performance regardless environment. This dissertation explored contribution precentral cortex this process motor adaptation. In first experiment, we recorded neural activity in rhesus monkeys that were trained perform visually-cued reaching while holding on robotic manipulandum capable changing task. Preparation and control correlated single cell throughout cortex, including primary five premotor areas. Precentral field potential was also modulated behavior, particularly beta gamma frequency bands. When novel introduced, changed manner specifically compensated for applied mirrored time course behavioral Force-related changes present well. Some these maintained following removal forces. Control data simulations revealed residual well described by model noisy adaptation redundant cortical network. second human subjects performed same paradigm after receiving transcranial magnetic stimulation transiently inhibit activity. Initial learning force environment normal but recall 24 hours later impaired relative controls. Taken together, results suggest distributed areas within involved recalibrating fit context initiating memory trace newly-experienced environments. Thesis Supervisor: Emilio Bizzi, M.D. Title: Institute Professor Chair: Ann M. Graybiel, Ph.D. Walter A. Rosenblith Neuroscience Reader: Christopher I. Moore, Mitsui CD Chair, Assistant