Which electrode is referred to as the central vertex electrode?

The central vertex electrode is identified as Cz in the 10-20 electrode placement system used for EEG. This electrode is located at the midpoint of the scalp, specifically at the vertex, which is the highest point on the human skull. The designation 'C' in Cz indicates its position in the 'central' region of the scalp, while the 'z' signifies its location at the vertex. Since this electrode is pivotal for assessing central brain activity, including motor and sensory functions, it is critically involved in various EEG analyses and interpretations.