President Joe Biden is under pressure to undergo cognitive testing even though his physician says he gets, and passes, an annual neurologic exam. But what can cognitive testing actually tell about a person’s brain health? And when, does the average older adult need one? Cognitive tests are brief screening tools, a 10-minute series of questions to assess different brain functions. They don’t diagnose health problems. A bad score is just a red flag that indicates a need for further testing. Generally it’s a good idea for seniors to get checked yearly to spot changes.