Somatosensory Stimulation Enhances the Effects of Training Functional Hand Tasks in Patients With Chronic Stroke
Abstract
Celnik P, Hummel F, Harris-Love M, Wolk R, Cohen LG. Somatosensory stimulation enhances the effects of training functional hand tasks in patients with chronic stroke.
Objective
To test the hypothesis that somatosensory stimulation would enhance the effects of training functional hand tasks immediately after practice and 1 day later in chronic subcortical stroke patients.
Design
Single-blinded and randomized, crossover study.
Setting
Human research laboratory.
Participants
Nine chronic subcortical stroke patients.
Interventions
Three separate sessions of motor training preceded by (1) synchronous peripheral nerve stimulation (PNS), (2) no stimulation, or (3) asynchronous PNS.
Main Outcome Measures
Time to complete the Jebsen-Taylor Hand Function Test (JTHFT time) and corticomotor excitability tested with transcranial magnetic stimulation.
Results
After familiarization practice, during which all patients reached a performance plateau, training under the effects of PNS reduced JTHFT time by 10% beyond the post-familiarization plateau. This behavioral gain was accompanied by a specific reduction in GABAergically mediated intracortical inhibition in the motor cortex. These findings were not observed after similar practice under the influence of no stimulation or asynchronous PNS sessions.
Conclusions
Somatosensory stimulation may enhance the training of functional hand tasks in patients with chronic stroke, possibly through modulation of intracortical GABAergic pathways.
aHuman Cortical Physiology Section and Stroke Neurorehabilitation Clinic, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
bDepartments of Physical Medicine and Rehabilitation and Neurology, Johns Hopkins University, Baltimore, MD
cDepartment of Neurology, Hamburg University Medical Center, Hamburg, Germany.
Request reprints to Leonardo G. Cohen, MD, Human Cortical Physiology Section, NINDS, NIH, Bethesda, MD 20817
Supported by the Intramural Research Program of the National Institute of Neurological Disorders and Stroke, National Institutes of Health; the Rehabilitation Medicine Scientist Training Program (grant no. 5K12HD001097); and the A. v. Humboldt Foundation (Feodor-Lynen grant).
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated.
ABSTRACT