Science-- there's something for everyone

Tuesday, August 28, 2012

Don’t sacrifice sleep to study


Here’s a little something for everyone going back to school in the fall. For optimal academic performance, is it better to sleep or to study? According to Cari Gillen-O’Neel, Virginia W. Huynh and Andrew J. Fuligni of the University of California, Los Angeles, if you have to choose between studying and getting a good night’s sleep, get some shuteye.

For their study, Gillen-O’Neel and her colleagues recruited 9th grade students from three Los Angeles schools.  For two weeks, daily reports were collected on study time, sleep time and academic functioning. The fortnight of data collection was repeated for the same kids in subsequent grades. Students who returned all fourteen reports received $30. If the reports were all filled in correctly, they also got a couple of movie passes. This resulted in an over 96% compliance rate.

Each day, the kids recorded exactly how much time they’d spent studying and how much sleep they’d gotten the previous night. The students also indicated how they’d done in school. Had they understood any new material that was presented? Had they done well on tests or quizzes?

So, what were the results? Deviating from the average study duration (which was just over an hour/night regardless of grade level) did not affect the next day’s academic performance for 9th graders. On the other hand, increased study time actually had a negative effect for older kids. Tenth through twelfth graders did progressively worse in school the more hours they studied. This rather counterintuitive result may be explained by the fact that study time and sleep time were inversely correlated. That is, the more time spent studying, the less time spent sleeping.

Understand that this does not mean that kids who don’t study do as well as kids who do. It just means that for kids who usually study, taking a night off didn’t affect their grades, whereas skipping sleep to cram in more study time did have an adverse effect. By all means, students who want to do well in school should spend time studying. They just shouldn’t sacrifice sleep to do so.

It actually does benefit students to study more as long as they don’t take the extra time away from sleep. The authors suggest that students develop a uniform and consistent study schedule so that long nights aren’t required, and that they take any needed extra study time away from socializing rather than from sleeping. I’m sure this advice will go over well with high school students, a demographic well known for not procrastinating and being willing to give up time with friends.