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Depression is a serious mental illness experienced by 1 in 15 adults in the United States each year. Many medications researched over the past few decades have been the main working tools in fighting this terrible disorder. Unfortunately for many, these medications prove to be insufficient, so scientists have been working to find new and improved ways to help patients suffering from depression.
The practice was first introduced in 1938, and has since then undergone many procedural adaptations, mirroring new advancements in medicine and technology. The severity of the treatments has led to a stigma among the public, yet it is important to understand that the treatments are safe and have been proven to be effective.
Electroconvulsive therapy (ECT) is a method used to combat depression and other illnesses such as acute manic episode, catatonia, and schizophrenia. ECT has been proven to have drastic effects on improving the conditions of patients in comparison to psychotropic medications. Initially, studies showed that the glial cell density within patients who had epilepsy was higher than other mental disorders. Because of this high cell density, researchers concluded that the epileptic seizures would be related to it and that inducing a seizure could potentially restore the glial cells necessary to perform cellular functions within the brain. The main question that we will investigate in this blog is how this process works and what neurobiological mechanisms are part of it.
Many explanations have been given for the efficacy of ECT, in which I will explain a few of them.
The first explanation requires the knowledge of neurons and how signals travel down their axons. Potential gradients formed by the flow of ions through ion-gated channels along the axon allow a signal to travel from the soma (body) to the dendrite branches where it sends the signal to the next neuron. The electrical impulse from ECT interacts with neurons directly by providing these cells with a large concentration of ions. These neurons will then fire signals at a rapid pace which produces the seizure-like effect. This convulsion is said to have a therapeutic effect and can help with various mental disorders.
ECT has also been found to help facilitate the creation, transport, and binding of neurotransmitters in the brain including serotonin and dopamine which can help relieve certain mental illnesses. ECT can also directly alter DNA which can code certain genes responsible for various functions. For example, treatments of ECT have been found to induce the gene Gadd45b which interrupts the creation of fibroblast growth factor 1 (FGF-1) which is involved in the regulation of neurogenesis. Overall, in a biochemical sense, ECT shows its effectiveness through its interconnection with various chemicals within the brain.
Lastly, it is notable to see the impact that ECT has on the brain’s neuroplasticity, its ability to form new neural connections. Regarding depression, many patients who receive treatment are seen to have an increase in volume over many different regions of the brain. MRI studies show that with many MDD (Major depressive disorder) patients, the volume of the hippocampus and amygdala will grow after merely 3 days of treatment. This data suggests that ECT can help increase the networking of our brains and possibly act as a helper in treating psychiatric disorders.
Although many of these biological networks are supported by data, it is still unsure about how exactly ECT works. Many of these processes have small gray areas where evidence from two separate studies will be contradictory. Also, some of the studies that prove the biological mechanisms mentioned were done on patients who have other disorders that could have affected the data. Nevertheless, this realm of neuroscience is one that will be explored more in depth in the near future and hopefully a full cure for depression will be possible through ECT.