Topographic approaches in human quantitative pharmaco-electroencephalography

The scalp distribution of the quantitative EEG effects of neuroactive compounds was studied in a number of pharmaco-EEG investigations, in which comparable procedures for EEG recording and processing were applied: power spectral and amplitude analyses were combined in all studies. Topographic differentiations were observed. These could include intrahemispheric and/or interhemispheric dissimilarities in the distribution of EEG effects common to the explored electrode derivations, as well as drug effects detectable only in distinct areas. The distribution could vary depending upon the EEG parameter considered; it was restricted to drug-related EEG modifications in all cases.