HOW DOES ECT WORK?

RESEARCHERS HAVE DISCOVERED SOME CHANGES IN THE BRAIN AFTER ECT, BUT HAVEN’T SETTLED ON ANY DEFINITIVE ANSWERS AROUND HOW IT WORKS. HERE ARE THE MAIN CONTENDERS…

HORMONES AND NEUROTRANSMITTERS IN THE BRAIN

ECT increases the levels of some neurotransmitters (chemical messengers that transmit signals between neurons) and hormones in the brain. Serotonin and dopamine are two neurotransmitters that increase after ECT. Serotonin regulates anxiety and reduces depression, while dopamine affects mood and motivation. Antidepressants have similar effects on the brain, but as ECT is generally faster acting and more effective than antidepressants, experts believe these changes cannot entirely account for ECT’s benefits.

INCREASES IN THE SIZE OF THE BRAIN’S EMOTIONAL PROCESSING AREAS

A recent study in humans showed that ECT increases the amount of grey matter in the brain’s hippocampus and the amygdala.

The hippocampus is involved in learning, memory and emotion, while the amygdala plays a role in the processing of emotions. However, this increase in volume of grey matter wasn’t correlated to noticeable changes in the mood of the patients, so more research is needed to establish whether or not this is a contributing factor.

CHANGES IN BRAIN CONNECTIONS

One study has shown that patients with severe depression have more connections between certain brain regions, including the prefrontal lobes, than healthy controls. Experts suggest that these connections could account for the ruminations and hyper-alertness that characterise some forms of depression, so decreasing these connections might help a patient. According to several studies, after ECT there are fewer connections between prefrontal lobes and other areas of the brain. But ECT may also build new connections in some areas of the brain, so more research is needed.