Tests cause most students considerable anxiety. That's good, because it usually motivates them to study. However, when it's time to take the exam, excessive anxiety can compromise how students perform. They miss questions that they knew the answer to, or so they tell us. We listen skeptically, but in some cases what students report is true. High anxiety makes it hard to focus on exam questions. Kristel Gallagher explains that the problem is made worse when they have trouble retrieving the information needed for the answer.