Several studies suggest TDCS may be a valuable tool in the treatment of depression, Anxiety Disorders, Chronic neuropathic pain, Alzheimer’s disease, Post- Stroke recovery, Fibromyalgia, Migraine, Parkinsonism, Tinnitus (ringing in the ears), and Multiple Sclerosis
TDCS has a significant effect on neurological activity in the targeted parts of the brain. Each device has an Anodal electrode and a Cathodal electrode. The Anodal electrode is the positively charged electrode and the Cathodal electrode is the negatively charged electrode.
The current flows from the cathodal electrode to the anodal electrode, creating a circuit. Thus, there are two types of stimulation with TDCS – Anodal and Cathodal stimulation.
Anodal stimulation acts to excite neuronal activity while Cathodal stimulation inhibits or reduces neuronal activity. In other words, TDCS stimulation changes brain function either by causing the neuron resting membrane potential to depolarize or hyper polarize.
When positive stimulation is delivered, the current causes a depolarization of the resting membrane potential, which increases excitability of brain cells and allows for more spontaneous cell firing. Negative stimulation causes a hyper polarization and decreases or inhibits neuron function.
One of the most important aspects of TDCS is its ability to achieve and cause sustained cortical (brain activity) changes even after the stimulation is ended. The duration of this change depends on the length of stimulation as well as the intensity of current.