|Image: Ingram Publishing|
Scientists know that depression affects the brain, but they still don’t know why some people respond to treatment and others do not. Now, UCLA researchers have shown in a large cohort of patients that electroconvulsive therapy (ECT) changes certain areas of the brain that play a role in how people feel, learn and respond to positive and negative environmental factors.
The team took three sets of images of 43 patients who were undergoing ECT: before their treatments, after their second session and within one week after they completed treatment. The images were compared to two sets of brain scans from 32 healthy people. The team imaged the hippocampus and amygdala in the research subjects before, during and after undergoing ECT and compared those images to scans of healthy brains. The scientists also showed that in patients with major depression, as the hippocampus increases in size, mood improves and parts of the hippocampus and amygdala change more with treatment.
The findings provide vital clues that could help doctors identify patients who will respond well to treatment. They would also help spare patients who won’t respond to treatment from taking drugs that ultimately won’t work for them, says Katherine Narr, PhD, associate professor of neurology.
ECT carries a certain stigma, but advances in anesthesia and the technology have improved the safety and reduced the side effects of the procedure. In addition, advances in high-resolution magnetic resonance imaging have allowed a more accurate measurement of the changes to the brain induced by ECT.
“ECT has been shown to be very effective for treating patients with major depression who don’t respond well to other treatments,” says Shantanu Joshi, PhD, assistant professor of neurology.
“People with smaller hippocampal size prior to starting treatment are less likely to respond as well to treatment.” Structural Plasticity of the Hippocampus and Amygdala Induced by Electroconvulsive Therapy in Major Depression,” Biological Psychiatry, March 2015