Reorganization of the brain, specifically the motor cortex surrounding the stroke, accounts for much of the observed neurological recovery following stroke. Not surprisingly, size of the stroke lesion has the greatest impact on neurological recovery in both animal and clinical research studies. Spontaneous recovery of lost function is possible after a cortical lesion, particularly if the lesion is small. Age correlates negatively with recovery; older individuals generally demonstrate slower and less complete recovery. However, age by itself is a poor predictor of functional recovery.