Ever heard the phrase you snooze, you lose? Well, science begs to differ.
Napping might carry the stigma of laziness, but what many don’t realize is that just because you're off your feet doesn't mean your inactive. In fact, your brain is hard at work during your siesta, and science is just now starting to make sense of it all.
There are many reasons to take a nap, such as making up sleep debt from shortened overnight sleep, preparing for an upcoming loss of sleep, or getting a little extra sleep for a boost of energy. Recently, scientists have even been asking questions about the role of sleep in learning. Questions like: Does sleeping after studying help memory? Do naps boost creativity? And more.
Here's a bit about what they've found. We'll break down different kinds of naps and all the ways that sleep can benefit your studying here.
[See also: Does time of day affect your ability to learn? Learn what is your optimal time to study for maximum memory retention.]
Does sleeping after studying help memory?
The first thing to know is that you can get some different benefits from naps of different lengths.
20-30 minute naps
Naps are beneficial to cognitive function even when they're short. Short naps typically only get us into the lightest stages of sleep, stage 1 and 2. Research has found that naps as short as 20 minutes can improve alertness, mood, memory, and performance.
30-60 minute naps
When taking a nap that’s around an hour long, your brain progresses through the lighter stages of sleep, Stages 1 and 2, and enters slow wave sleep (SWS)—also considered your "deep sleep". It is thought that declarative memories, or memories of your personal experiences and learned facts, benefit from this type of sleep, which helps in taking short-term memories to long-term storage.
While a very brief nap (6-10 minutes), compared to remaining awake, may temporarily preserve memory, a longer nap that gets into SWS (30-60 minutes) is needed to keep memories around for a while and to protect them from interfering information. In fact, the longer you are awake during the day, the more SWS you will get when you fall asleep, and naps in the afternoon may benefit these memories the best.
60-90 minute naps
Longer naps (60-90 minutes) allow the brain to progress further into sleep, transitioning from SWS into rapid eye movement (REM) sleep. This type of sleep may benefit memories that provoke an emotional response because of the connectivity between memory and emotion centers of the brain during this stage. REM sleep has been positively correlated with memory for emotional information, which is typically better remembered than neutral information.
Naps and creativity
Napping has also been found to boost creativity by allowing connections to form between related items, promoting the abstraction of embedded rules and lists common to learned items, and facilitating the integration of new information into old. These types of memory transformation allow a more flexible use of learned information that informs future decision-making.
Research led by a leading expert on the positive benefits of napping at the University of California, San Diego School of Medicine suggests that REM sleep enhances creative problem-solving. The findings may have important implications for how sleep, specifically REM sleep, fosters the formation of associative networks in the brain.
The study shows that REM directly enhances creative processing more than any other sleep or wake state. The authors said, “We found that—for creative problems that you’ve already been working on—the passage of time is enough to find solutions. However, for new problems, only REM sleep enhances creativity.”
It appears REM sleep helps achieve such solutions by stimulating associative networks, allowing the brain to make new and useful associations between unrelated ideas. Importantly, the study showed that these improvements are not due to selective memory enhancements.
Regulating your emotions
Aside from everything a little snooze can do for your memory and creativity, it can also improve the way you emotionally react to the world. Who doesn’t feel cranky when tired? That crankiness may cause you to view the world in a more negative light, and most likely get negativity back in return.
A daytime nap, especially one with REM sleep, has been shown to reduce negative reactivity and promote a happier outlook, compared to remaining awake and feeling increased reactivity, particularly to threat-related stimuli. This reduced emotional reactivity even extends to physiological responses, with habituation to negative images occurring over approximately 90 minutes of napping.
What about feeling groggy?
There are a couple caveats to longer daytime napping. Waking up from deep SWS or REM sleep can result in a feeling of grogginess and disorientation, called sleep inertia. However, this should pass in no more than 30 minutes.
Also, while napping in the afternoon may have more of that memory promoting SWS, napping late in the afternoon or early evening can disrupt your normal overnight sleep. So don’t push it too late.
Finally, napping works best for you if you can make it a habit, incorporating it into your routine. However, even if this is not possible, the benefits of an occasional nap are well worth it.
Take that nap if you're tired
Does sleeping after studying help memory? Absolutely—it helps you consolidate what you learn so that you can remember it later. In fact, spacing out your studying between naps is an effective way to study. If you build that strategy into your study habits, you'll be doing yourself a favor.
So, don't feel guilty about taking that nap. You'll actually be better prepared to write your test if you're well-rested than if you spend that extra 20 to 90 minutes cramming.
[Learn more about optimizing your brain health for learning]
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