[Computerized quantitative topo-electroencephalography].

A method is described which has been developed to topographically display the values of spectral EEG analysis from 11 electrodes on each hemisphere and 5 electrodes on the midline. The EEG from 16 channels at a time is multiplexed and sampled at 3.2 kHz.

[Topographic aspects of drug-induced fast rhythms in quantitative topo-electroencephalography].

The topographical aspects of fast rhythms induced by different psychotropic drugs have been studied in patients by means of a previously described method. This method is based on the spectral analysis of 28 EEG channels over both cerebral hemispheres. The spectral parameters, computed over 2 min 40 sec, are put into a data base.

[Multivariate correspondence analysis of a visually screened EEG. Application to a study of psychotropic drugs compared with placebos (author's transl)].

Eighty-seven EEG recordings were obtained from 9 healthy volunteers, medical students who were part of a controlled, double-blind, randomized study. After a first control recording, they received orally, at 1 week interval, either 3 placebos or 3 compounds: yohimbine chlorhydrate (4 mg), propranolol (40 mg), a psychotropic compound in experimentation. The polygraphic recordings were obtained 2 or 6 h after placebos or active compounds.

Intra- and interhemispheric EEG differences quantified by spectral analysis. Comparative study of two groups of schizophrenics and a control group.

In this work we have studied comparatively the relationships between alpha intensity, alpha frequency, root-mean-square amplitude and their standard deviations, versus the location of the four recorded EEG channels: left and right rolando-parietal, left and right parieto-occipital. Twenty-four spectral parameters were computed for each 5-min EEG recording, in the eyes closed situation. The hebephrenic group (36 EEGs from six patients) presented higher values of alpha intensity and RMS amplitudes with low coefficient of variation when compared with the other groups.