A new research suggests a mechanism that helps explain how anxiety can disrupt the decision-making process and result in bad choices.
According to findings in The Journal of Neuroscience published by scientists in the Department of Neuroscience at the University of Pittsburgh in Pennsylvania, anxiety disengages the prefrontal cortex (PFC).
The PFC an area of the brain that a pivotal role in flexible decision-making. In order to find out which neurons were directly affected by anxiety, the scientists analyzed the brain cells, or neurons, in the prefrontal cortex (PFC) of two groups of rats as they completed a decision-making task, in which they had to make a decision about which choice was most logical for getting a reward. One group of rats received a low-dose anxiety-inducing drug before dealing with the task, while the other group received a placebo injection.
The scientists made two important observations. First, anxiety often causes bad decision-making, especially when there were conflicts or distractions. Second, bad decisions made under distress involve the “unclamping” of very specific PFC neurons.
The data shows that anxiety has an exquisitely selective effect on neuronal activity supporting decision making, says Bita Moghaddam, Ph.D., the lead author of the study. So far, scientists have mostly studied anxiety in animal models in the context of fear and measured how brain cells react to a threatening situation. However, human anxiety is devastating, not merely because of how the person feels, but also because it can interfere with nearly all aspects of daily life including decision making, Moghaddam says.
As with many individuals who experience anxiety but go through day-to-day life and make decisions, the anxiety-ridden rats accomplished the decision-making task and, in fact, did not perform too badly. However, they made far more mistakes when the correct choice involved ignoring distracting information.
“A brain locus of vulnerability for these anxiety-induced mistakes was a group of cells in the PFC that specifically coded for choice. Anxiety weakened the coding power of these neurons”, Moghaddam said.
“We have had a simplistic approach to studying and treating anxiety. We have equated it with fear and have mostly assumed that it over-engages entire brain circuits. But this study shows that anxiety disengages brain cells in a highly specialized manner.”, Moghaddam commented on the findings
The study gives us a better understanding of the brain mechanics behind anxiety and decision making. Moghaddam believes this could lead to better treatment of anxiety in human and, afterwards, better outcomes for plenty of psychiatric and addictive disorders.