NEW YORK: Some persons would have made you wonder with their optimism? Even if the whole world would turn against them, they would walk ahead gracefully with the mere back up of their attitude. Likewise, there are some people who would have irked you by being pessimistic without any valid reason?
Now, a group of scientists at the Massachusetts Institute of Technology (MIT) have found the root of the matter. They have identified a brain region that could generate pessimistic moods in disorders such as anxiety or depression that leads people to focus more on the possible downside than the potential benefit in a stressful situation.
In a study tested on animals, researchers have found that stimulating caudate nucleus — a brain region linked to emotional decision-making –induced animals to make negative decisions.
They gave far more weight to the anticipated drawback of a situation than its benefit, compared to when the region was not stimulated. This pessimistic decision-making could continue through the day after the original stimulation.
The findings could help scientists better understand how some of the crippling effects of depression and anxiety arise, and guide them in developing new treatments.
“We feel we were seeing a proxy for anxiety, or depression, or some mix of the two,” says Ann Graybiel, an MIT Institute Professor, a member of MIT’s McGovern Institute for Brain Research, and the senior author of the study, which appears in the Aug. 9 issue of Neuron. “These psychiatric problems are still so very difficult to treat for many individuals suffering from them.”
The paper’s lead authors are McGovern Institute research affiliates Ken-ichi Amemori and Satoko Amemori, who perfected the tasks and have been studying emotion and how it is controlled by the brain. McGovern Institute researcher Daniel Gibson, an expert in data analysis, is also an author of the paper.
The caudate nucleus, has within it regions that are connected with the limbic system, which regulates mood, and sends input to motor areas of the brain as well as dopamine-producing regions. The study showed that the animals gave far more weight to the anticipated drawback of a situation than its benefit, compared to when the region was not stimulated.