Anxiety Undermines Good Decision Making, Study Finds

For people living with anxiety, decision making can be overwhelming. Now, a recent study published in The Journal of Neuroscience has uncovered exactly what’s happening in your brain when you struggle to make a decision in a state of anxiety. 

According to the study, which tested the decision-making skills of anxious rats, anxiety disengages the prefrontal cortex (PFC), a region of the brain that plays an important role in flexible decision making. Researchers injected a mild dose of an anxiety-inducing drug into one group of rats, and a placebo into another, and tested their ability to make decisions in order to reach a reward. At the same time, they monitored the activity of the rats’ PFC to determine exactly how neurons were affected by anxiety.

Researchers found that both groups of rats performed relatively well in tests. However, any time decision making involved distractions, or the need to ignore unnecessary information, anxious rats began making more wrong choices. Researchers observed numbing of PFC neurons in anxious rats, and believe that this impairment of the PFC is what made it more difficult for the anxious rats to make decisions on the fly.

“A brain locus of vulnerability for these anxiety-induced mistakes was a group of cells in the PFC that specifically coded for choice,” explains researcher Bita Moghaddam. “Anxiety weakened the coding power of these neurons.”

While most of us experience anxiety at some point, chronic anxiety can have a major impact on many aspects of daily life, says Moghaddam. Earlier this month, a study found that people with generalized anxiety disorder were more likely to interpret harmless things as threats. Moghaddam’s work adds to those findings, showing yet another of the subtle, but potentially harmful, effects of anxiety. 

“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,” explains Moghaddam. “But this study shows that anxiety disengages brain cells in a highly specialized manner.”