Electrode

An electrical plate, wire or rod used to make contact with a non-metallic part of a circuit..

Source: GreenFacts

When studying the brain by means of electrodes, these are either placed on the scalp (electroencephalography - EEG), under the surface of the scalp and skull directly on the brain’s surface (electrocorticography), or into specific brain areas.

Deep brain stimulation (DBS) is a surgical treatment where electrodes are implanted in certain areas of the brain and are stimulated using an electric pulse generator. DBS can help some people with depression resistant to therapy and other brain diseases such as Alzheimer’s disease.

Source: GreenFacts