This paper presents the results of the practical use of artificial neu
ral networks in the field of EEG analysis. It describes the general me
thodology of application as well as a case study of a discrimination o
f depressive and psychotic patients using 16-channel long-term EEG dat
a prepared by classical pre-processing (spectral decomposition). This
study shows advantages and current limits concerning different levels
of generalisation capabilities using a representative application exam
ple.