The structure of the brain is such that it has several areas, each having its own set of functions that directly controls a particular organ or an organ system of the body. The lateral habenula is one such area. This tiny area is the focus of attention in terms of multiple researches. The scientists have discovered that this is the area responsible for the decisions we take and the choices we make.
A study published in Nature Neuroscience says the lateral habenula, a region of the brain linked to depression and avoidance behaviors, has been largely misunderstood and may be integral in the process of making decisions.
The lateral habenula is one of the smallest parts of the brain. Scientists previously linked it to depressive symptoms when they saw patients improve when the part was turned off through deep brain stimulation – a procedure involving electrodes being implanted in the brain that are controlled by a pacemaker. The region had also been thought to be involved in avoidance behavior.
Evolutionarily, the lateral habenula is considered to be one of the oldest regions of the brain, according to the scientists – they just had not realized what it actually did until this study.
In an experiment lead by Prof. Stan Floresco of University of British Columbia’s Department of Psychology and Brain Research Centre, there were a few rats whose behaviors were assessed. The rats were given ‘rewards’ against certain ‘costs;’the rewards here being small rewards, i.e., small quantities of food and large rewards, i.e., large quantities of food. Like humans, the rats tend to choose larger rewards when risks, in this case, the amount of time they had to wait before receiving food, were low and preferred smaller rewards when such risks were higher.
Says Prof. Stan Floresco: “These findings clarify the brain processes involved in the important decisions that we make on a daily basis, from choosing between job offers to deciding which house or car to buy. It also suggests that the scientific community has misunderstood the true functioning of this mysterious, but important region of the brain.”
These findings throw new light into the way depression is treated. Turning off the lateral habenula may be beneficial for depressed people.
Scientists say that this is not due to the patients feeling happier. Instead, this act may make them choose to avoid the things that make them depressed.
