Electroconvulsive therapy (ECT) is the most acutely effective treatment for severe, sometimes life-threatening, depression.
However despite a robust scientific evidence-base, ECT use remains limited mainly because of cognitive side effects, especially concerns about its effect upon memory function and autobiographical memory in particular.
Now new research, led by Professor of Psychiatry Declan McLoughlin from Trinity College Dublin's Department of Psychiatry and Institute of Neuroscience, shows that by modifying the therapy, memory side-effects can be reduced whilst maintaining ECT's undoubted effectiveness.
The study, which has just been published in the American Journal of Psychiatry, shows that by altering the position on the head of the electrodes cognitive side-effects can be minimised.
ECT involves the deliberate induction of a brief seizure to the patient by applying a small electrical charge to the brain, under anaesthetic. Worldwide the most common position of the electrodes is 'bitemporal' -- on both sides of the head at the temples.
This research employed the 'unilateral' approach, where one electrode was placed on the right temple and the second placed near the top of the head just to the right side.
Commenting about the importance and implications of his study, Professor McLoughlin commented: "We believe that our findings justify considering high-dose unilateral ECT as the preferred option when considering ECT for treating severe, sometimes life-threatening, depression.
"This study will hopefully help to improve the acceptability and availability of this effective, though often misunderstood, treatment. This is especially so for those severely ill patients who are likely to benefit from ECT but do not have ready access to it and experience delayed treatment and unnecessarily prolonged suffering."
In Ireland, North America, the UK and northern Europe, ECT is generally given two or three times weekly and an average course consists of eight sessions.
ECT is believed to work by increasing the production of growth factors within the brain and improving the connectivity between nerve cells, particularly within a region of the brain called the hippocampus that has important roles in emotion and memory.
- At least 70% of those treated with ECT in Irish clinics are deemed to have had either a "complete recovery" or a "significant improvement".
- For most patients memory side-effects arising from ECT are transient. However some patients complain of persisting problems related to autobiographical memory, which is one's store of personal memories and an important part our sense of self. Such problems may be confounded by persisting depression as well as the effect of depression itself on the brain and memory function.
- Declan McLoughlin is Research Professor of Psychiatry and belongs to Trinity College Dublin's School of Medicine.