Illustrative model: – What our theory says is that ECT appears to cause disturbances in the brain, among other things, studies have shown changes in proportional metabolic concentrations, says Leif Oltedal Photo: MMIV
The article was published in Biological Psychiatry. The research is a collaboration between the Department of Radiology and the Department of Mental Health at Hauckland University Hospital and the University of Bergen (UiB). The research group is led by Leif Altidal of the Mohn Center for Medical Imaging and Visualization UiB, and Altidal is also the chief medical officer of the Department of Radiology at the University of Hawkeland Hospital. The group leads a collaboration in which more than 20 other research groups contribute. The study’s lead author is Olga Therese Osdal.
Electrostimulation therapy is a treatment for some mental disorders that uses a low dose of electricity, and this method was previously called electroconvulsive therapy. The treatment is primarily used for severe depression where other treatments haven’t improved, according to The great Norwegian encyclopedia.
What we did in this study is to review all articles examining MRI patients before and after ECT. Based on the findings, we propose a new theory about how ECT works, says Ultedal.
In general, we now believe that ECT will disable, strengthen, and rewire patients’ brains. If the condition becomes too severe, there will be many side effects. If there is a little discomfort, you lose the effect. In other words, it is believed that there is an optimal dose of ECT.
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In previous work, Oltedal says, the research group rejected the theory that changes in one part of the brain called the hippocampus could explain the needed antidepressant effect of ECT.
– We found at that time that there were changes in large areas of the brain after ECT, but these changes could not explain the effect of the treatment.
like muscle paralysis
– What our theory says is that ECT appears to cause brain disorders among other things, studies have shown changes in concentrations of metabolites that are proportional to that. I wouldn’t call it a damage – we think it’s a temporary glitch. It’s like running or exercising first for a long time and then muscle cramps for a short time, Oldall says.
Ultidal explains that electrical stimulation treatment is usually given three times per week. People are stimulated to initiate epilepsy-like seizures under controlled conditions.
This slightly disrupts brain function and helps dissolve the closed connections that maintain depression.
In addition to disruption, we believe that stimulation strengthens the brain, that is, brain connections can be strengthened. New brain cells are also likely to form. It has to do with the color of the brain and its ability to change, which we think increases with ECT.
Long-term ECT will be able to help a patient return to healthy patterns of thinking and feelings, Oltedal says. That the brain changes and that depressive thoughts and feelings are less after treatment.
Source: Ousdal et al. (2021) Biological Psychiatry
The new theory has three components: discontinuation, reinforcement, and reconnection:
1) ECT causes a short-term disturbance of brain function (epilepsy, treatment 2-3 times a week, gray curve). This helps dissolve the closed bands that maintain depression (blue curve).
2) In addition, the brain and neurons are stimulated to grow cells and connections (green curve).
3) The latter can contribute to new, more favorable coupling patterns (i.e. no lower blue curve). If the dosage is optimal, there will be few side effects (red curve).
Clinical treatment
Ute Kessler, associate professor at UiB and chief medical officer of the division of ECT in the Department of Mental Health at Hawkeland University Hospital, is a study co-author.
What do you think is most important in this explanatory model?
ECT is an effective treatment for major depression. At the same time, some patients have memory problems. It is difficult to determine in advance who will experience these side effects. If our hypotheses are confirmed, this study could help customize treatment for each individual patient so that side effects can be minimized, Kessler wrote in an email to Dagens Medisin.
Will ECT change, if so, how and what it means for patients?
Today an attempt is made to explain any memory problems that arise during the ECT sequence, but not in a systematic way. Comprehensive knowledge of factors that may contribute to individual patient differences can change patient follow-up procedures during the ECT series and modify treatment parameters.
Finally, Kessler wrote that the publication in question is basic research and does not directly improve patient treatment.
But this research is important, both in explaining how ECT works in the long term, and in explaining individual differences in effect and side effects.
