For years I have issued this advice to Chem 201 students before each exam, “Don’t stay up too late studying,” I say. “It doesn’t help. You need to get good sleep in order to make good long-term memories.” I have repeated this message over and over again not because I’m a “Mommy” who hates to see exhausted students working on o-chem exams (although I do hate to see this), but because my dim appreciation of sleep research has been that the science supports my advice.
So I was pretty excited when I saw an article in the 6 June 2014 issue of Science magazine that helps explain the relationship between sleep and memory. “Memories – getting wired during sleep” (p. 1087) reports how researchers have found a way (p. 1173) to observe changes in nerve fibers (in mice) that occur when the mice learn a new task. Specifically, the researchers examined the number and location of “dendritic spines.” These spines are structures that form in specific locations on a nerve fiber as a mouse improves its ability to perform particular tasks. Sleep promotes the formation of spines (and also improved task performance) while sleep deprivation prevented spines from forming (and also reduced task performance).
Neurophysiology is not my field, but these results are really exciting. Imagine being able to see structural changes in individual nerves that are associated with learning! And also discovering that sleep is essential for these changes to occur. Very, very cool.
And, of course, that advice of mine: if you really want a good score on the next exam, study. Then get to sleep. Good sleep.