*The following is excerpted from an online article posted on PsychCentral.
Students who take practice tests before the real test — a strategy known as retrieval practice — tend to achieve higher scores, even under high-stakes pressure, according to a new study by researchers at Tufts University. The findings suggest that the practice tests protect one’s memory against the negative effects of stress.
The findings are published in the journal Science.
In experiments involving 120 student participants, individuals who learned a series of words and images by retrieval practice showed no impairment in memory after experiencing acute stress. On the other hand, students who engaged in traditional study methods — re-reading material to memorize it — remembered fewer items overall, particularly after stress.
“Typically, people under stress are less effective at retrieving information from memory. We now show for the first time that the right learning strategy, in this case retrieval practice or taking practice tests, results in such strong memory representations that even under high levels of stress, subjects are still able to access their memories,” said senior study author Ayanna Thomas, Ph.D., associate professor and director of the graduate program in psychology at Tufts.
“Our results suggest that it is not necessarily a matter of how much or how long someone studies, but how they study,” said Amy Smith, graduate student in psychology at Tufts and corresponding author on the study.
For the study, the researchers asked participants to learn a set of 30 words and 30 images through a computer program. The words and images were displayed one at a time for a few seconds each. To simulate note taking, participants were given 10 seconds to type a sentence using the item immediately after seeing it.
One group studied the items using retrieval practice, taking timed practice tests in which they freely recalled as many items as they could remember. The other group used study practice. For these participants, items were re-displayed on the computer screen, one at a time, for a few seconds each. Participants were given multiple timed periods to study.
After a 24-hour break, half of each group was placed in a stress-inducing scenario. These participants were required to give an unexpected, impromptu speech and solve math problems in front of two judges, three peers, and a video camera.
They also took two memory tests, in which they were asked to recall the words or images they had studied the previous day. These tests were taken during the stress scenario and 20 minutes after, to examine memory under immediate and delayed stress responses.
The remaining half of the groups took their memory tests during and after a time-matched, non-stressful task.
Among participants who had learned through retrieval practice, stressed individuals remembered an average of around 11 items out of each set of 30 words and images, compared to 10 items for their non-stressed counterparts.
Participants who learned through study practice remembered fewer words overall, with an average of seven items for stressed individuals and an average of a little under nine items for those who were not stressed.
“Even though previous research has shown that retrieval practice is one of the best learning strategies available, we were still surprised at how effective it was for individuals under stress. It was as if stress had no effect on their memory,” Smith said.
“Learning by taking tests and being forced to retrieve information over and over has a strong effect on long-term memory retention, and appears to continue to have great benefits in high-stakes, stressful situations.”