As much as society tends to romanticize incessant, caffeine-fueled workaholism, this lifestyle isn’t necessarily the best thing for our mental functioning. A recent study from a team of psychologists and neuroscientists at the University of Edinburgh strongly suggests that your memory works best when you’re rested:
[The researchers] asked a small group of normally aging elderly men and women to recall as many details as possible from two stories they were told. Following one of the stories (but not always the same one for all the participants), the men and women were instructed to relax, take a brief break and close their eyes for 10 minutes in a dark room. Following the other story, those same participants were instead distracted with a new task, spotting the differences between pairs of nearly identical images. Overall, the study participants remembered many more details of whichever story they heard before they were told to rest — and their striking memory boost persisted even a full week out after the story-telling .
Though this study focuses on the elderly, a demographic that tends to be especially concerned with memory retention, the results have implications that extend beyond geriatrics. There are preexisting studies which indicate that people of all ages perform significantly better at activities requiring short-term memory when allotted several minutes to rest between their introduction to the material and their regurgitation of the material . The recent study from the University of Edinburgh elevates the importance of rest’s role in memory retention by offering evidence that rest not only enhances short-term memory consolidation, it enhances long-term memory retention as well.
With multiple studies offering evidence that sleep plays a critical role in memory retention and consolidation, scientists may be closer to figuring out an answer to the elusive question: why do we sleep? Reflecting on his research on sleep and memory at the Beth Israel Deaconess Medical Center, Matthew Walker, Ph.D. offers a neurobiological explanation for sleep’s positive affect on memory retention:
The cerebellum, which functions as one of the brain’s motor centers controlling speed and accuracy, was clearly more active when the subjects had had a night of sleep. At the same time, the MRIs showed reduced activity in the brain’s limbic system, the region that controls for emotions, such as stress and anxiety. The MRI scans are showing us that brain regions shift dramatically during sleep. When you’re asleep, it seems as though you are shifting memory to more efficient storage regions within the brain. Consequently, when you awaken, memory tasks can be performed both more quickly and accurately and with less stress and anxiety. The end result is that procedural skills — for example, learning to talk, to coordinate limbs, musicianship, sports, even using and interpreting sensory and perceptual information from the surrounding world — become more automatic and require the use of fewer conscious brain regions to be accomplished .
Scientists think this might explain why human infants spend so much time sleeping: they are consolidating procedural memories about how to control their tiny, complex bodies.
Next time you have to memorize and retain a large amount of information, don’t pull an all-nighter–just be restfully aware of the content you have to memorize, get some sleep, and review the material when you wake up. You might be pleasantly surprised to see how productive you can be while resting.