How Much Sleep Do I Actually Need to Retain Information for Exams? And How I Can Get More?

Published: Jun, 07 2019

Whether you’re a college student heading into finals, a high school student preparing for AP exams or the SAT, or an adult pursuing a new course of study, knowing that you have a test looming can be stressful. You may already be aware that getting the right amount of sleep is critical to making sure the studying you do is effective. It’s easy to lose sight of that fact, however, when anxiety convinces you to spend another hour going over your lecture notes instead of going to bed. Surely if a little studying is good, more is always better, right?

The reality is that neglecting sleep in favor of studying will not produce the results you want. The infamous “all-nighter” is more likely to sabotage your exam grade than it is to boost it. Getting the right amount of sleep is critical for forming memories and retaining information—and persistent sleep deprivation can make you unfocused and forgetful, unable to learn or remember the information you need to.  In order to get the right amount of sleep needed for a test, you need to cultivate good sleep habits in general.

So what is the right amount of sleep? Doctors recommend general ranges of sleep times based on age, as the need for sleep varies both by age and for individuals. According to the National Sleep Foundation, teens (14–17) need 8 to 10 hours of sleep per night, and young adults (18–25) need 7 to 9 hours of sleep per night. Even mature adults still need 7 to 9 hours of sleep each night to be fully rested. Knowing the exact right amount for you is more subjective, however. How you feel during the day is your best guide to knowing if you’re getting enough rest. If you’re often drowsy in the afternoon, have trouble dragging yourself out of bed, and need copious amounts of coffee to prop you up through classes, then you’re not sleeping enough. The goal is to wake up feeling rested and alert, with the energy you need throughout the day.

Although we are still learning about how sleep affects the brain, scientists do know that getting adequate sleep is important to learning. According to the National Institutes of Health, sleep deprivation can reduce your ability to learn new information by up to 40 percent. On the positive side, sleeping after you’ve learned something improves your ability to remember what you’ve learned. Scientists believe that non-REM sleep, especially the deeper stages, is important for encoding memories and for preparing the brain for new learning, while REM sleep (the stage associated with dreaming) helps to link together related memories, possibly improving problem-solving. The combination of these benefits makes it obvious why it’s important to get regular sleep before class and after study sessions.

Unfortunately, getting the right amount of sleep when you’re headed into an exam may seem impossible. Most people don’t deprive themselves of sleep on purpose—instead, they fall into bad patterns that they don’t know how to correct. In order to figure out how to get more sleep for an exam, it’s important to understand some of the reasons why you may not be getting enough rest already:

  1. Time management problems: You may tell yourself that you simply don’t have enough time to sleep. However, it’s often more accurate to say that we don’t put a priority on sleep, so it ends up at the bottom of the list of our things to do.
  2. Poor sleep habits: If you routinely stay up too late on your phone or computer, crash out for long emergency midday naps, or use caffeine to substitute for rest, trying to get to bed early the night before the big test isn’t going to make up for the sleep you’ve missed.
  3. Poor sleep environment: Sleeping in a dorm or other roommate situation, where you don’t always have control over the noise level or when other people are coming and going, can make it difficult to get sleep on the schedule you need.
  4. Stress: When you’re anxious about doing well in a class, the stress that results can make it hard to fall asleep, especially when you most need to.

Thankfully, none of these problems is insurmountable. However, addressing them may take a little forethought. Here’s what to do:

  • Schedule your sleep: Plan for your rest the same way you would plan to go to class or a study session. In the weeks leading up to a test, keep your focus on the things you need to do, and cut out or postpone things that can wait until after your exam is done.
  • Get serious about bedtime: Things like downing a late-night latte, exercising after dinner, or browsing YouTube or your Instagram feed as you’re getting ready for bed will make it harder to fall asleep on schedule. Stay off the screens and away from stimulation in the hour or so before bed.
  • Create a sleep oasis: Do whatever you can to make your sleep environment more conducive to rest, especially if you’re sharing your living space. Make sure your mattress is supportive and comfortable—even a dorm mattress can be improved with a mattress topper. Use a sleep mask to block out stray light and earplugs or a white noise machine to cut down on disruptive background noise.
  • Stick to a bedtime routine: Unwind before you crawl into bed with a relaxation activity such as deep breathing or drinking a warm cup of caffeine-free tea. If you tend to lay awake thinking of what you need to do the next day, try writing down a to-do list before you go to bed to purge the worry that you’re going to forget something.

You’ll get more sleep for an exam when you treat it like the necessity it is, rather than an afterthought or a luxury. You’ll also set yourself up for success, because the rest you get will make your time learning and studying more effective. Rather than focusing on how much sleep you need for a particular test, you should think instead of how much sleep you need to feel good every day. When you’ve achieved that, then doing well on your exams will come more easily.