Electrophysiological mechanisms of action of electroconvulsive therapy

In spite of the guidelines and consensus on its indications and application, electroconvulsive therapy (ECT) continues to be one of the therapeutic procedures with less knowledge on its mechanism of action. It is interesting to evaluate the way in which the factors that modulate the convulsant activity can be modified by this therapy and its relation with the therapeutic effect. The aim of the present article is to review, in the context of neurobiological theories, the bibliography regarding the electrophysiological mechanisms of action of ECT, mainly the anticonvulsant hypothesis. Having better knowledge about these mechanisms can achieve an improvement in the clinical practice and provide a starting point to search for alternative treatments based on the same physical bases. After doing a study of all the papers and reference books, those works which, according to their methodology and design, provide relevant scientific information with regard to the principal topic of this review and that have been published between 1993 and 2007 were selected. In order to provide better consistency to the text, a series of articles prior to 1993 that were considered important within the setting studied have been included, since they establish the theoretical bases of ECT and have been frequently mentioned after their sublication. The scientific evidence obtained is systematized into three sections: basic concepts, neurophysiological hypotheses and electrophysiological findings.