Studying for exams, preparing for interviews, work presentations – sometimes there just aren’t enough hours in the day to get all that information to stay in your head.
With so much to do, it’s often tempting to burn the candle at both ends, studying or working late into the night.
As you’ll see in this article, however, researchers have repeatedly found that sacrificing sleep for more study generally doesn’t help. In fact, it’s often associated with worse academic performance.
Why sleep is important for learning
There are many theories about why we sleep, with it probably serving several different functions. Your brain is very active when you sleep, and some sleep experts believe that you’re still learning long after your head hits the pillow.
They think that this happens through what’s known as memory consolidation. This is the process by which the brain turns information that you acquire during the day into lasting memories. And many research studies have shown that sleep deprivation adversely affects short and long-term memory.
Can you learn new information in your sleep?
Sleep-learning refers to the supposed ability of your brain to learn new information from material heard during sleep.
Perhaps you’ve seen adverts for courses or audiobooks that you can listen to during your sleep to learn a new skill or language?
They sometimes claim that you can learn effortlessly whilst you sleep. While this might sound like the perfect solution to your revision worries, research has shown you can’t learn completely new information while asleep.
Back in the 1950s, some interesting research showed subjects learned nothing new once asleep. And in the 67 years since then, nobody has proven otherwise.
So although sleep may play a role in consolidating your memories, you still have to do the groundwork of learning the information while you’re awake.
Research shows that less sleep leads to worse results when staying up late to study
Sometimes it’s necessary to work long hours to prepare for an exam or presentation or to finish an important project. And many students force themselves to stay awake late into the night studying. But is this really in your best interest?
Professor Cari Gillen-O’Neil and her colleagues from the University of California did some research into what happens when students stay up late to study. And they found that sacrificing sleep can be counterproductive.
They found that academic outcomes were strongly linked to how much sleep the students had the previous night. Even if they stayed up late to study more, their lack of sleep had a negative impact on their test results. They would have done better studying less and getting more sleep.
These negative effects are made worse the more nights you work late. Pulling multiple late night study sessions in a row leads to poorer and poorer results.
The researchers didn’t find any evidence of individual characteristics playing a role in the effects of sleep on their study.
This means that even if you feel you can work effectively with little sleep, your performance is still likely to be worse than it would be if you were well rested.
Professor Gillen-O’Neel is keen to stress that her findings shouldn’t be interpreted as saying study isn’t important. It certainly is, but so is sleep.
Research shows bad sleep leads to worse academic performance
Dr. Giuseppe Curcio and his colleagues from the University of Rome looked at the effects of bad sleep on learning.
They examined how young people, from school children to university students, performed at academic tasks the morning after a bad night’s sleep.
Unsurprisingly, those who had slept poorly felt tired throughout the day, affecting their mood and their sociability. And tired students also struggled to learn and retain new information.
Dr. Curcio observed that ‘higher cognitive functions’ were most affected. So poor sleep led to worse attention, a lessened ability to solve problems and reduced academic performance.
Tiredness lowers your ability to engage with complex tasks, assess mental data and take important decisions. And these are some of the core skills you need during an exam or high-pressure work assignment.
Research shows sleep is associated with GPA results and motivation
In 2008, Fred Danner, PhD, of the University of Kentucky, looked at the sleep habits and academic performance of 882 high school freshmen.
He found that the hours of sleep per school night were significantly positively associated with GPA and level of motivation. He also found that sleeping more was associated with lower levels of emotional disturbance and ADHD. He does add the caveat that these are associations, rather than evidence that sleeping less lowers grades etc.
However, he makes an interesting point about why students should value their sleep more than what they think students should do:
Lack of sleep should no longer be considered a traditional adolescent rite of passage because it can have serious consequences.Fred Danner
What can you do if you sleep badly?
Japanese researchers found that napping helped students counteract some of the negative effects of only getting 4 hours’ sleep the previous night.
They discovered that a 15 minute nap taken after lunch improved alertness and performance, particularly during the typical mid-afternoon ‘slump’.
So if you’re revising while sleep deprived, adding naps to your schedule during the bad days might help to mitigate some of the damage, and hopefully keep your brain working at its best.
The studies considered here show that sleep is a vital part of studying, learning and professional preparation. Giving up sleep for a few more hours of work is counterproductive.
You’re likely to be less effective the next day, and perform worse than you would have done had you studied less and got a good night’s sleep.
I’ve already discussed the benefits of napping, but what other techniques could you use to help you sleep when work or revision is piling up?
The answer is likely to depend on how you study. Preparation, routine and a healthy diet will help you make the most of the daytime hours.
Most importantly, understanding the effect that sleep has on your performance (and the fact that less sleep leads to worse grades) means that sleep itself should be seen as an important revision technique.
Working smarter, rather than longer, could be the key to success.