People who are worriers know about the toll it takes. They are often exhausted at the end of a day spent worrying about their work, what a friend said about them, how their child is doing at school and what they should make for dinner.

There is a way to reduce the grip of worry, a new study finds: Spend a little time writing down what is bothering you.

“Worrying takes up cognitive resources; it's kind of like people who struggle with worry are constantly multitasking — they are doing one task and trying to monitor and suppress their worries at the same time,” explained Hans Schroder, the lead author on a new study that looked at the neural basis of worry and the way writing about your worries can free the brain of their effects.

“…[I]f you get these worries out of your head through expressive writing, those cognitive resources are freed up to work toward the task you're completing and you become more efficient.”

Schroder's study provides the first neural evidence for the way writing your worries down can free up your brain, reducing stress and giving you more mental bandwidth. “Our findings show that if you get these worries out of your head through expressive writing, those cognitive resources are freed up to work toward the task you're completing and you become more efficient,” Schroder, a doctoral student in psychology and a clinical intern at Harvard Medical School's McLean Hospital, said.

College students participating in the Michigan State University had been identified as chronically anxious using a screening measure of anxiety known as error-related negativity or ERN. This is an electrical brain signal, measured with an electroencephalogram or EEG, that the brain registers when it detects a mistake. Students in the study completed a computer-based task that measured their response accuracy and reaction times, an anxiety-producing challenge with plenty of opportunities to make mistakes.

Before the task, half of the participants wrote down for eight minutes their deepest thoughts and feelings about the upcoming task; the other half, in the control condition, wrote what they had done the day before.

Both groups were roughly equal in speed and accuracy, but EEGs of the students made it clear that the expressive-writing group performed the computer-based task more efficiently, using fewer brain resources and allowing their brain to run more efficiently.

“Here, worried college students who wrote about their worries were able to offload these worries and run more like a brand new Prius, whereas the worried students who didn't offload their worries ran more like a '74 Impala — guzzling more brain gas to achieve the same outcomes on the task,” said Jason Moser, associate professor of psychology, who worked with Schroder and Tim Moran, a research scientist at Emory University, on the study.

So, the next time worry leaves you feeling stuck, take a few minutes to write down how you are feeling. It just may give your brain the mental efficiency it needs to get things done. It may also leave you feeling better at the end of the day.

The study is published in Psychophysiology and is available without subscription.