During this week, we attended two excursions. A topic that came up in parts of the trips was how depression can be treated using electroconvulsive therapy, and more specifically transcranial magnetic stimulation. The idea of doing this is fascinating, as it would mean depression could be localized in the brain, and the effects that cause depression (or the effects caused by depression as well, presumably) can be reversed with relative ease. Depression seems to be such a complex issue that one wouldn’t think could be simply “turned on or off.” Perhaps this only effects depression that doesn’t have an active contributing cause for it, such as a death of a loved one? Although of course all thoughts are caused by some brain activity, I doubt the cure would in essence, overwrite thinking to prevent negative thoughts.
First, the area where effects of depressions are happening must be located, usually one side of the prefrontal cortex of the brain is less active than the other. After knowing which area to interact with, TMS works by first placing electromagnetic coils on a subject’s forehead. A pulse is created by a magnet, which stimulates the desired nerve cells. This pulse should cause no significant side effects apart from a slight tingling sensation, and consciousness is not interrupted. Some slight hand or feet movement might also be observed. In rare cases where the treatment is usually applied incorrectly to the wrong area of the brain, an epileptic episode can occur, but there have been no lethal consequences. This treatment needs to be repeated for up to 40 minutes a session, multiple times per week for months to have the desired, long lasting positive effects against depression. Once successful, depression should be lowered or removed for many months with little to no continuing treatment. For some people there is no change in their level of depression, although for more than half of the subjects tested there is. Perhaps this calls back to my earlier speculation on different forms of depression?
Some of the people who have been able to benefit from TMS include people who suffer from post-natal depression, when depression is accompanied by psychotic features, bipolar disorder, mania, schizophrenia and those who do not respond to antidepressant therapy. There are those who cannot receive TMS therapy, for example those with brain stimulators, metallic implants, shrapnel, tattoos with magnetic sensitive ink or aneurysm clips or coils.
There are other forms of ECT, implanting a device under the collarbone skin which periodically stimulates the brain is called VNS, but it is rarer and only recommended to long term reoccurring depressive patients. As the technology improves, hopefully more people will be able to benefit from this treatment, and the long lasting effects of it are made more accurate and permanent!