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For most students, September means back to school. And, for high-school seniors, it's also a sign that the SAT is right around the corner. At one point, the SAT stood for Scholastic Aptitude Test, now it carries no particular name at all, but it is one of the major exams used to evaluate students for college admission. Simply put, there is often a lot riding on this test - especially for students with big college dreams.
It might come as no surprise that stressing about doing well on an important exam can backfire, leading students to "choke under pressure" or to score less well than they might otherwise score if the stakes weren't so high. You might not have known, however, that the pressures of a big test can reach beyond the exam itself - stunting the cognitive systems that support the attention and memory skills we use every day.
Recently, a group of psychologists1 at Cornell University's medical school got hold of two dozen medical students who were spending the better part of a month preparing for an intensive academic exam. The medical students had been convinced to take a break from their studying and spend a few hours doing cognitive tasks while their brains were scanned using fMRI. Another group of people were also scanned. This "control" group was the same age as the medical students, had the same sleep habits, and similar years of education and also worked in demanding jobs. The big difference was that this control group was not facing an upcoming high-stakes exam.
The tasks everyone did in the fMRI scanner were fairly simple, but the stressed-out medical students performed poorly on them. The medical students were sluggish when they had to switch from identifying the color of an object presented on the computer screen (say, a red triangle) to identifying which direction it was moving. The medical students were easily distracted from whatever task they were doing in a way that the non-medical students were not. Moreover, the more people reported feeling stressed out, the worse they did on these tasks.
When the researchers peered inside everyone's brains to see how they were functioning, they found that the stress that the medical students were feeling was reducing the cooperation of different parts of the brain that usually work together to support thinking and reasoning. In particular, the prefrontal cortex (dorsal lateral prefrontal cortex or DLPFC) didn't seem to be working as hard for the medical students and was not as in sync with the rest of the brain as it should have been.
The prefrontal cortex, among its many functions, houses working-memory. In a nutshell, working memory can be thought of as a flexible mental scratch pad. It helps you keep information in mind and work with this information while at the same time keeping irrelevant information out. The medical students were not using their powerful brain resources to their full potential, most likely because of the stress they were under.
The good news is that the effects of stress on the brain are reversible. A month or so after the medical students took their exam, their brains were scanned again. This time, the medical students' brain functions looked just like the non-stressed out control group as they performed the demanding attention and memory tasks.
These results are intriguing because they reinforce our understanding of the ways that stress changes the brain. Being under pressure alters how different areas of the brain communicate. The prefrontal cortex works less well and decouples - or stops talking - to other brain areas that are also important for maximal cognitive horsepower. The brain generally works in concert, as a network. When a particular brain area stops communicating as much with other areas, this can have dire consequences for our thinking and reasoning capabilities.
So, what does this mean for stressed out high-school seniors? First off, putting too much emphasis on a test may carry consequences beyond the exam room. Yes, it may be hard to deny the importance of the SAT given our test-obsessed culture, but there are some fairly simple exercises that can reduce the testing emphasis. For instance, research shows that simply downplaying the importance of this one snippet of performance can help - remind students that there are many ingredients in a successful college application and this 4 hour testing period is only one of them. Getting students to reflect on some of their positive qualities (maybe they are an athlete, a musician, a good friend) can also help them realize that this one score does not define them. Finally, there is evidence that having students to spend some time writing or journaling about their exam worries can actually boost the working memory (a.k.a cognitive horsepower) needed to ace a test - it's as if the worries get left on the paper and thus aren't as likely to wreak havoc in our heads. Although these may seem like simple moves, the end result may be less pressure at exam time and better performance in all activities students engage in leading up to the big testing day.
For more exam time insights, check out my forthcoming book Choke
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1 Liston, C., McEwen, B. S., & Casey, B. J. (2009). Psychosocial stress reversibly disrupts prefrontal processing and attentional control. Proceedings of the National Academy of Sciences, USA, 106, 912-917.
