Feeling nervous can do more damage to memory than most people expect. You show twenty boys and twenty girls a set of twenty-five objects for two minutes. In the calm round, they write down every object they can recall. In the anxious round, each person is told just before reciting that they are being graded and watched by an assessor. Under calm conditions, both groups remember about seventeen to eighteen objects on average. Under that sudden stressful situation, the number drops to fewer than seven — a cut of more than half.

Feeling nervous or pressured can sharply reduce how well your brain remembers. Under calm conditions, twenty boys and twenty girls each recall about seventeen to eighteen objects on average after viewing a set of twenty-five items for two minutes. When each person is told just before reciting that they are being graded and watched by an assessor, that number drops to fewer than seven. A sudden stressful situation can cut short-term memory by more than half.