ELECTROCONVULSIVE therapy (ECT) and electroencephalography (EEG) were developed within several years of each other in the early 1930s, and the effects of ECT on the ictal and interictal EEGs were reported soon thereafter. The EEG effects were massive and consistent; it seemed natural to view this EEG change as a concomitant, a precondition, or even an explanation of the clinical effects of ECT. These views were translated into hypotheses that were tested and presented in a large literature that goes back to the 1940s.
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At least 3 domains have been studied in the literature involving interictal EEG: the treatment, the EEG, and the clinical outcome. The treatment variables include the position of the ECT electrodes, the stimulus intensity, and the number of treatments given at the time of the EEG. The EEG variables include the topographic distribution over the scalp (the number, location, and connections of
Volavka J, Czobor P. Interictal Electroencephalographic Effects of Electroconvulsive TherapyCan They Elucidate Mechanism of Action?. Arch Gen Psychiatry. 1996;53(9):826-827. doi:10.1001/archpsyc.1996.01830090074010