A broad range of studies have shown that sleep is good for not just our physical well-being, but also for our psychological well-being, too. Now, researchers have proved that sleep, even in short power naps, has the power to improve memory recall better than if we don't sleep at all.
In their experiments, researchers studied the hippocampus region of the brain, the place where the brain converts short-term memories into long-term ones. In electroencephalogram (EEG) readings, they specifically looked for "sleep spindles," which are bursts of quick vibrations in the brain. The more sleep spindles that show up on an EEG, the stronger a person's memory is.
"We suspect that certain types of memory content, particularly information that was previously tagged, is preferentially consolidated during this type of brain activity," says Saarland University researcher Axel Mecklinger.
In their study, researchers taught volunteers 90 single words, as well as 120 nonsense word pairs, or two unrelated words, such as milk and taxi. This prevents volunteers from learning words that are already familiar with each other, making the test results more accurate. Because the volunteers had not heard the words paired together before, it forces them to use their memory, rather than their knowledge of familiar words and phrases.
Then, one group took a nap for 45 to 60 minutes, while the control group watched DVDs. Once quizzed on the learning material, the napping group performed significantly better than the control group, especially in remembering the nonsensical word pairs. Also, the nap group's memory was as good as it was before they slept and right after learning the words.
"A short nap at the office or in school is enough to significantly improve learning success. Wherever people are in a learning environment, we should think seriously about the positive effects of sleep," says Mecklinger. "Enhancing information recall through sleeping doesn't require us to stuff bulky tomes under our pillow. A concentrated period of learning followed by a short relaxing sleep is all that's needed."
Other studies about napping have also yielded positive results. Naps can help adults adjust from the side effects of too little sleep and naps even help babies learn better. One study even shows that naps combined with coffee is better at keeping you alert in the afternoons more than just coffee alone.
So sneak in those naps when you can: you'll feel better and recall more information after.
Photo: Francisco Osorio | Flickr
