[The effects of ordinary provocation on the power density spectrum. A clinical electroencephalographic study...

In the search for methods which might increase the discrimination of the EEG, the power density spectra of a random sample of patients during different conditions were analysed. Power density spectra were made during eyes closed, eyes open, after hyperventilation, during photic stimulation, and during auditory stimulation. It proved that the spectra may change under different provocation tests, sometimes in a rather peculiar way. The conclusion was, that these analyses improve explicit the EEG diagnosis, a problem however is the time required for spectra interpretation.