Dynamic organization of primary motor cortex output to target muscles in adult rats. I. Long-term patterns of reorganization following motor or mixed peripheral nerve lesions.

摘要: These experiments examined the ability of adult motor cortex to reorganize its relationship with somatic musculature following nerve lesions. Cortical output organization was assessed by mapping areal extent movements evoked intracortical electrical stimulation in anesthetized rats. Output patterns normal rats were compared those that had received either a forelimb amputation or facial transection 1 week 4 months earlier. In both experimental conditions some representations increased. Stimulation thresholds required elicit expanded at below levels. After amputation, area from which shoulder could be low enlarged. Sectioning branches innervate vibrissa enlarged and eye/eyelid areas; these enlargements appeared occupy former area. results indicate amount controlling group muscles strength between cortical locus target is modified lesions mammals. They also show are sufficient produce this change changes can appear as early 7 days peripheral injury.