NEW YORK (Reuters Health) - Many patients with neurological disorders focus on the potential obstacle to a given situation rather than on potential benefit, a new study suggests. Neurodegenerative disorders, such as anxiety or depression, are usually attributed to diseases that arise in the nervous system.
Researchers at the Massachusetts Institute of Technology have identified a region of the brain that can generate this kind of pessimistic state of mind. In animal tests, they showed that stimulating this region, known as the guilty nucleus, led them to make more negative decisions. They have given much greater weight to the expected handicap than their own, compared to the time when the region was not stimulated. This pessimistic decision can continue until the day after the original stimulus.
These types of decisions, requiring weight options with positive and negative elements, tend to cause great concern. The study also showed that chronic stress significantly affects this type of decision-making: more stress often leads to the choice of high-risk and high-performance options.
In the new study, researchers wanted to know if they could reproduce an effect that often appears in people with depression, anxiety or obsessive-compulsive disorder. These patients tend to participate in ritual behavior designed to combat negative thoughts and put more weight on the potential negative outcome of a particular situation. Researchers believe that this type of negative thinking can affect decision-making to avoid approaches.
To test this hypothesis, the researchers stimulated the guilty nucleus, a region of the brain associated with emotional decision-making, with a small electric current since the animals were given a reward (juice) coupled with an unpleasant stimulant. Of the air in the face). In each experiment, the relationship between reward and stimuli was different, and animals could choose whether to accept or not.
This type of decision requires a cost-benefit analysis. If the reward is high enough to balance the air of the mouth, the animals will choose to accept it, but when this ratio is too low, they will reject it.
When the researchers stimulated the guilty nucleus, the cost-benefit calculation became biased, and the animals began to avoid the structures they would have accepted. This continued until after the stimulation ended and could be seen the next day, and then gradually disappeared.
This finding suggests that animals have begun to reduce the value of the reward they previously wanted, and focused more on the cost of the risk motive.