Ten Percent Electrode System for Topographic Studies of Spontaneous and Evoked EEG Activities

.An 81-electrode system is described which is designed for topographic studies of spontaneous and evoked EEG activities. This method combines the standard leads of the International 10–20 System with supplementary electrodes applied midway between leads of the 10–20 system or electrodes in turn situated between 10–20 leads. Auxiliary electrode designations refer to the underlying brain areas and to adjacent leads of the 10–20 method. The utilization of this “10% system” is suggested to promote standardization.