What generates pessimistic mood?

New York Scientists 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 situationIn a study tested on animals researchers at the Massachusetts Institute of Technology MIT have found that stimulating caudate nucleus a brain region linked to emotional decisionmaking induced animals to make negative decisionsThe 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 dopamineproducing regionsThe 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 stimulatedThis pessimistic decisionmaking could continue through the day after the original stimulationWe feel we were seeing a proxy for anxiety or depression or some mix of the two said Ann Graybiel a professor at the MITIn the study which appeared in the journal Neuron the team wanted to see if they could reproduce an effect that is often seen in people with depression anxiety or obsessivecompulsive disorderThe team stimulated the caudate nucleus with a small electrical current as animals were offered a reward juice paired with an unpleasant stimulus a puff of air to the faceThe results showed that the costbenefit calculation became skewed and the animals began to avoid combinations that they previously would have acceptedThis continued even after the stimulation ended and could also be seen the following day after which point it gradually disappearedThis result suggests that the animals began to devalue the reward that they previously wanted and focused more on the cost of the aversive stimulusThis state weve mimicked has an overestimation of cost relative to benefit Graybiel notedThe researchers also found that brainwave activity in the caudate nucleus was altered when decisionmaking patterns changedThere must be many circuits involved she saidBut apparently we are so delicately balanced that just throwing the system off a little bit can rapidly change behaviourCatch up on all the latest Crime National International and Hatke news here Also download the new midday Android and iOS apps to get latest updatesThis story has been sourced from a third party syndicated feed agencies Midday accepts no responsibility or liability for its dependability trustworthiness reliability and data of the text Midday managementmiddaycom reserves the sole right to alter delete or remove without notice the content in its absolute discretion for any reason whatsoever