It’s the night before an exam. Do you stay up late to continue studying or do you go to sleep to get a good night’s rest? Many will go with the former option, choosing a few extra hours of studying over sleep. However, it is well known that bursts of brain activity during sleep, known as sleep spindles, are correlated with strengthening the memory of recently learned information.
A study from Current Biology presents new information on how sleep facilitates memory. Sleep spindles appeared in brain areas that were active in the study participants while they were awake and learning a task. Furthermore, stronger spindles in these brain areas were associated with better recall following sleep.
The researchers developed a set of demanding memory tasks, named the “memory arena,” in which participants learned the spatial arrangements of objects in a circle.
While the participants were in the process of memorizing the arrangements, their brain activity was measured with an electroencephalogram. An EEG measures electrical activity in the brain by attaching electrodes, small metal discs, to the scalp.
Participants then took a two-hour nap during which their brain activity was measured using an EEG as well. Memory for the arrangements was assessed prior to taking the two-hour nap as well as following the two-hour nap.
While the participants were napping, the researchers found stronger sleep spindles in the brain areas that were active during their memorization of the arrangements. Researchers also discovered that stronger sleep spindles in the brain areas correlated with better recall.
This study supports the role of spindles in memory; in other words, how sleep spindles play a role in boosting memory. Furthermore, this study is the first to measure brain activity during learning to support the relationship between sleep spindles during memorization and sleep.
After knowing how post-learning sleep can actually facilitate memory consolidation, sleep sounds like the best option for the night before an exam!