Non-invasive Electrical Brain Modulation: A New Avenue for Treatment?

The failure of many drug trials testing newer therapeutics for brain disease has spawned investigation of novel treatments. Here we briefly review recent non-invasive transcranial electrical stimulation (tES) studies that suggest modulation of brain activity can be done safely and effectively, even when subjects do not feel the stimulation. In contrast to Deep Brain Stimulation (DBS), an accepted surgical therapy for diseases such as Parkinson's, tES is completely noninvasive. Moreover, tES studies have demonstrated changes in motor performance, working memory, decision making, and somatosensory function. Galvanic Vestibular Stimulation (GVS) is also a form of electrical stimulation, but selectively activates vestibular afferents. Given the widespread cortical regions influenced by vestibular input, GVS can also have a myriad of effects, including partial amelioration of hemi-neglect, a known complication of right hemispheric stroke. In the future, it may be possible to judicially select pulsatile stimuli so that tES and/or GVS are tailored to the subject, or even the particular state of the individual, which may result in a quantum leap in efficacy of this exciting new technology.