Stimulation through simulation? Motor imagery and functional reorganization in hemiplegic stroke patients

A key factor influencing reorganization of function in damaged neural networks of the adult brain is stimulation. How to stimulate motor areas of patients with paralyses is a formidable challenge. One possibility is to use internal movement simulations, or motor imagery, as an alternative to conventional therapeutic interventions that require voluntary limb movements. Before this alternative can be entertained, two preliminary issues must be resolved. First, do internal movement simulations involve the same neural circuits as comparable overt actions? Second, are motor-impaired populations capable of imagining movements they can no longer perform? Here, I show that under specific conditions, answers to these questions are affirmative. Further, I discuss preliminary evidence that internally simulating movements may induce functional reorganization of the contralesional hand representation of a chronic, densely hemiplegic, cerebral vascular accident (CVA) patient. (C) 2004 Elsevier Inc. All rights reserved.