The efficacy of use of transcranial direct current stimulation in the treatment of neurological disease & defect

Abstract

Non-invasive brain stimulation techniques have recently become popular in the treatment of neurological diseases and disorders. Transcranial direct current stimulation [tDCS] is a method of brain stimulation whereby direct electrical current is passed through the intact scalp into the nervous tissue, producing lasting changes in neural activity of the stimulated areas. The polarity, or direction, of current flow in relation to the orientation of neural networks determines whether neuronal activity is enhanced or inhibited. The lasting increases or decreases in neuronal activity produced by tDCS have been used to shape cognitive function in various neurological diseases and disorders, including stroke, Parkinson’s disease, Alzheimer’s disease and depression. Currently, the mechanism of action for the effects caused by tDCS is not well understood. The goal of this thesis is to evaluate the efficacy of tDCS as a therapy for these brain disorders. The vast majority of these studies found strong and largely consistent evidence for the improvement of symptoms following tDCS for periods lasting up to several weeks when applied appropriately. While further refinement is needed to expand the effectiveness of tDCS treatment, the future looks promising.