The present review focuses on quantitative EEG findings in schizophren
ia and depression. Methodology and results as described in the literat
ure are compared both for conditions at rest and under activation. In
schizophrenia approaches dealing with the description of acute states
and prediction of therapeutic response offer the most promising result
s. The context of changes between delta, alpha and beta have emerged a
s the most outstanding finding and there are connections between the l
atter and Crow's Type I and II syndromes. With regard to depression al
pha- and beta-power findings prevailed. Imbalance of frontal and parie
tal laterality were found to be in accordance with depression concepts
as known from neuropsychology. Present day pluralism with regard to m
ethodology reduces comparability and validability of results. Homogeno
us standards must be achieved on an international level in order to in
crease the significance of concepts.