As anyone who has ever struggled to leave the comfort of a cozy bed knows, sleep matters. In fact, sleep deficits are linked to such a litany of physical and psychological disorders that one has to wonder why a solid 8 or more hours a night isn’t prescribed medically for children. Adolescents, existing as they do in an attenuated state of development, need a whole lot more sleep (9.25 hours) than they typically get (7 hours). No wonder teens can be so moody.
Yes, sleep supports optimal physical health, emotional well-being, and better decision making. But if that’s not enough for you, let’s throw in better grades and test scores. Researchers learn again and again that people often learn better when sleeping before and after–but obviously not during–instruction or study.
A large group of scientists, mostly from French universities, explored one easily appreciated aspect of this dynamic: Relearn Faster and Retain Longer – Along With Practice, Sleep Makes Perfect. The title really tells the tale. The researchers investigated whether sleep-dependent memory consolidation could help to save practice time during relearning. In other words, does sleeping after studying help improve retention?
During two sessions occurring 12 hr apart, 40 participants practiced foreign vocabulary until they reached a perfect level of performance. Half of them learned in the morning and relearned in the evening of a single day. The other half learned in the evening of one day, slept, and then relearned in the morning of the next day. Their retention was assessed 1 week later and 6 months later. We found that interleaving sleep between learning sessions not only reduced the amount of practice needed by half but also ensured much better long-term retention.
Getting enough sleep isn’t just good for your body; it’s also good for your grades and test scores. High quality sleep demands at least one hour of screen-free time before slumber, so make that study time instead to leverage the information consolidation benefits of sleep. Even better, wake up and study the same material again. Working smart like this will save you many sleepless nights later!