Electrode Electrode An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit (e.g. a semiconductor, an electrolyte, a vacuum or air). The word was coined by William Whewell at the request of the scientist Michael Faraday from two Greek words: "elektron", meaning amber (from which the word electricity is derived), and "hodos", a way. The electrophore, invented by Johan Wilcke, was an early version of an electrode used to study static electricity. An electrode in an electrochemical cell is referred to as either an "anode" or a "cathode" (words that were coined by William
Chronic electrode implant that glial encapsulation, i.e. gliosis, insulates the electrode from nearby neurons, thereby hindering diffusion and increasing impedance, extends the distance between the electrode and its nearest target neurons, or creates an inhibitory environment for neurite extension, thus repelling regenerating neural processes away from recording sites"”. Either activated astrocytes or buildup of cellular debris from cell death around the electrode would act to insulate the recording sites from other, active neurons. Even very small increases in the separation between the electrode and local nerve population can insulate the electrode completely, as electrodes must be within 100 um to get a signal.