Mode of action of electroconvulsive therapy: an update

Abstract

SummaryIt has become acceptable for psychiatrists to say that they simply do not know how electroconvulsive therapy (ECT) works. This frame of mind runs the risk that there will be no expectation that psychiatrists remain familiar with seminal studies on the mode of action of ECT. This article is intended as a reminder of these studies and illustrates how the original theories have evolved. This evolution has been brought about largely by modern brain imaging techniques in human studies and in patients treated with ECT. These new findings will be set in the context of contemporary ideas about the neuroanatomy of mood disorders and the cellular mechanisms of the long-term effects of antidepressant treatments.

Electroconvulsive shock attenuated microgliosis and astrogliosis in the hippocampus and ameliorated schizophrenia-like behavior of Gunn rat

“…Nevertheless, views on ECT vary; some researchers consider that it is probably ineffective and certainly causes brain damage, while others think it is completely safe and the most effective treatment available in psychiatry [ 4 ]. Both the generalized seizure and the dose of electricity used seem to be important for the therapeutic effect of ECT, which has multiple, varied, and lasting effects on the CNS [ 5 , 6 ]. However, the exact mechanism of therapeutic action of ECT remains unknown.…”

Electroconvulsive therapy for refractory anxiety disorders

“…Similar to affective and psychotic illnesses, they can be life threatening with adverse effects on both physical and mental wellbeing. ECT remains an effective treatment for affective, catatonic and psychotic illnesses when other treatment options have been exhausted with little subsequent functional improvement 1,2,12 . However, despite some promising very low quality data on its effects in refractory OCD, its related disorders, and refractory PTSD , there remains an absence of evidence from regulated, well designed trials ( ie those that have followed strict protocols with validated, standardised assessments and stringent inclusion criteria).…”

“…There is evidence to indicate that electroconvulsive therapy (ECT) is an effective treatment for both acute, refractory and life threatening forms of affective and catatonic mental illness 1,2 . See Box 1 for a summary of clinical indications 3–8 …”

“…T here is evidence to indicate that electroconvulsive therapy (ECT) is an effective treatment for both acute, refractory and life threatening forms of affective and catatonic mental illness. 1,2 See Box 1 for a summary of clinical indications. [3][4][5][6][7][8] Reported remission rates with ECT for acute, severe depression are over 50% and 60-80% when used firstline treatment in severe depressive episodes.…”

Electroconvulsive therapy: a life course approach for recurrent depressive disorder

“…There are lots of theories on how ECT works, but there are still large gaps in our understanding of its mechanism of action; however, this is also the case with antidepressants 5. ECT is sometimes used as a continuation or maintenance treatment in people who have been known to respond to ECT in order to try and prevent further relapses and recurrences of the index illness 6…”