Elucidation of biochemical basis of the antidepressant action of electroconvulsive therapy by human studies.

A variety of direct and indirect human studies indicate that electroconvulsive therapy (ECT) enhances transmission in a number of key transmitter systems in the brain. These include the noradrenergic system, the serotonergic system, and the GABAergic and dopaminergic systems. On the other hand, ECT probably reduces cholinergic transmission. The enhanced transmission effects have been related to the antidepressant effect of ECT, whereas the cholinergic effect has been attributed to its effects on memory and cognition as well as depression. This paper will briefly review the research methodologies and results from clinical studies of neurotransmitter effects of ECT. Promising future directions of research will be indicated.