Repeated sessions of noninvasive brain DC stimulation is associated with motor function improvement in stroke patients.

PURPOSE Recent evidence has suggested that a simple technique of noninvasive brain stimulation - transcranial direct current stimulation (tDCS) - is associated with a significant motor function improvement in stroke patients. METHODS We tested the motor performance improvement in stroke patients following 4 weekly sessions of sham, anodal- and cathodal tDCS (experiment 1) and the effects of 5 consecutive daily sessions of cathodal tDCS (experiment 2). A blinded rater evaluated motor function using the Jebsen-Taylor Hand Function Test. RESULTS There was a significant main effect of stimulation condition (p=0.009) in experiment 1. Furthermore there was a significant motor function improvement after either cathodal tDCS of the unaffected hemisphere (p=0.016) or anodal tDCS of the affected hemisphere (p=0.046) when compared to sham tDCS. There was no cumulative effect associated with weekly sessions of tDCS, however consecutive daily sessions of tDCS (experiment 2) were associated with a significant effect on time (p< 0.0001) that lasted for 2 weeks after treatment. CONCLUSIONS The findings of our study support previous research showing that tDCS is significantly associated with motor function improvement in stroke patients; and support that consecutive daily sessions of tDCS might increase its behavioral effects. Because the technique of tDCS is simple, safe and non-expensive; our findings support further research on the use of this technique for the rehabilitation of patients with stroke.

[1]  R. Racine,et al.  Long-Term Depression and Depotentiation in the Sensorimotor Cortex of the Freely Moving Rat , 2000, The Journal of Neuroscience.

[2]  Sergio P. Rigonatti,et al.  A sham-controlled, phase II trial of transcranial direct current stimulation for the treatment of central pain in traumatic spinal cord injury , 2006, PAIN.

[3]  Sergio P. Rigonatti,et al.  A sham stimulation-controlled trial of rTMS of the unaffected hemisphere in stroke patients , 2005, Neurology.

[4]  M. Nitsche,et al.  Facilitation of Implicit Motor Learning by Weak Transcranial Direct Current Stimulation of the Primary Motor Cortex in the Human , 2003, Journal of Cognitive Neuroscience.

[5]  Á. Pascual-Leone,et al.  Improved picture naming in chronic aphasia after TMS to part of right Broca’s area: An open-protocol study , 2005, Brain and Language.

[6]  Steven D. Freedman,et al.  A Sham-Controlled Trial of a 5-Day Course of Repetitive Transcranial Magnetic Stimulation of the Unaffected Hemisphere in Stroke Patients , 2006, Stroke.

[7]  E. Khedr,et al.  Therapeutic effect of repetitive transcranial magnetic stimulation on motor function in Parkinson's disease patients , 2003, European journal of neurology.

[8]  J. Rothwell,et al.  Therapeutic trial of repetitive transcranial magnetic stimulation after acute ischemic stroke , 2005, Neurology.

[9]  Sergio P. Rigonatti,et al.  Transcranial direct current stimulation of the unaffected hemisphere in stroke patients , 2005, Neuroreport.

[10]  M. Nitsche,et al.  Pharmacological Modulation of Cortical Excitability Shifts Induced by Transcranial Direct Current Stimulation in Humans , 2003, The Journal of physiology.

[11]  M. Hallett,et al.  Modeling the current distribution during transcranial direct current stimulation , 2006, Clinical Neurophysiology.

[12]  Á. Pascual-Leone,et al.  Interindividual variability of the modulatory effects of repetitive transcranial magnetic stimulation on cortical excitability , 2000, Experimental Brain Research.

[13]  L. Cohen,et al.  Influence of interhemispheric interactions on motor function in chronic stroke , 2004, Annals of neurology.

[14]  L. Cohen,et al.  Effects of non-invasive cortical stimulation on skilled motor function in chronic stroke. , 2005, Brain : a journal of neurology.

[15]  Lumy Sawaki,et al.  Effects of Somatosensory Stimulation on Use-Dependent Plasticity in Chronic Stroke , 2006, Stroke.

[16]  L. Cohen,et al.  Mechanisms underlying recovery of motor function after stroke. , 2004, Postgraduate medical journal.

[17]  R. H. Jebsen,et al.  An objective and standardized test of hand function. , 1969, Archives of physical medicine and rehabilitation.

[18]  Richard S. J. Frackowiak,et al.  How does transcranial DC stimulation of the primary motor cortex alter regional neuronal activity in the human brain? , 2005, The European journal of neuroscience.

[19]  M. Ridding,et al.  Increased cortical excitability induced by transcranial DC and peripheral nerve stimulation , 2003, Journal of Neuroscience Methods.

[20]  N. Ward.  Functional reorganization of the cerebral motor system after stroke , 2004, Current opinion in neurology.

[21]  Steven C Cramer,et al.  Motor cortex stimulation for enhancement of recovery after stroke: Case report , 2003, Neurological research.

[22]  A. Gershon,et al.  Transcranial magnetic stimulation in the treatment of depression. , 2003, The American journal of psychiatry.

[23]  P. Rossini,et al.  Motor cortical disinhibition in the unaffected hemisphere after unilateral cortical stroke. , 2002, Brain : a journal of neurology.

[24]  M. Nitsche,et al.  Pharmacological approach to the mechanisms of transcranial DC-stimulation-induced after-effects of human motor cortex excitability. , 2002, Brain : a journal of neurology.

[25]  Markus Zahn,et al.  Transcranial magnetic stimulation and stroke: A computer-based human model study , 2006, NeuroImage.

[26]  Ann M. Stowe,et al.  Post-infarct cortical plasticity and behavioral recovery using concurrent cortical stimulation and rehabilitative training: A feasibility study in primates , 2003, Neurological research.

[27]  Á. Pascual-Leone,et al.  A Controlled Clinical Trial of Cathodal DC Polarization in Patients with Refractory Epilepsy , 2006, Epilepsia.