Writing down your anxieties before a stressful situation like an exam or speech greatly boosts your performance, a new study suggests.
Working memory is lodged in the prefrontal cortex and is a sort of mental "notepad" that allows people to "work" with information relevant to the task at hand.
But the notepad can also be filled with anxieties – thus losing brain power.
In order to test the theory, researchers recruited 20 college students and gave them two short maths tests.
On the first test, students were told simply to do their best.
Before the second test, researchers created a situation designed to produce stress, by saying students who performed well would receive money and that other students were depending on their performance as part of a team effort.
Students also were told that their work would be videotaped, and that maths teachers would review it.
Half of the students then received 10 minutes to write expressively about their feelings about the forthcoming test, and the other half was told to sit quietly.
The writing group performed significantly better than the control group, increasing their marks by five per cent on the first test.
The non-writing group saw their marks drop by 12 per cent from the first test.
"It seemed that the non-writing group suffered from choking or from what I call 'paralysis from analysis'," said Prof Beilock.
"The writing group actually improved their performance."
In another experiment researchers found that writing down your worries worked best in the most anxious pupils creating a "level playing field" with their more confident colleagues.
Students highly anxious about taking tests who wrote down their thoughts before the test received an average grade of B+, compared with the highly anxious students who didn't write, who received an average grade of B-.
"Writing about your worries for 10 minutes before an forthcoming exam levelled the playing field such that those students who usually get most anxious during exams were able to overcome their fears and perform up to their potential," Prof Beilock said.
"In fact, we think this type of writing will help people perform their best in variety of pressure-filled situations — whether it is a big presentation to a client, a speech to an audience or even a job interview."
The research mirrors previous work that has shown that writing poems, songs and journals can reduce emotional turmoil.
The University of California found that the mere action of writing about an emotion was a way of calming down the brain and re-establishing mental balance.
The study is published in the journal Science.
Prof Beilock is one of America's leading experts on "choking under pressure" — a phenomenon in which talented people perform below their skill level when presented with a particularly challenging experience.
Her recently published book, Choke: What the Secrets of the Brain Reveal About Getting It Right When You Have To, gives advice on how to avoid choking in situations ranging from high-stakes exams to important business presentations and athletic competitions.