Figure 1: [Untitled picture of a student sleeping]. Retrieved October 31, 2013, from http://www.students.ubc.ca/livewelllearnwell/learn-about-wellness/sleep-nutrition-exercise/lack-of-sleep/.
Now that midterms are coming to a close, it is important that we put away the late night cramming, all-nighters and the high-caffeine drinks for a while – at least until the next round of exams.
Even though most of us understand the benefits of getting a good night’s sleep, we tend to think of sleep as a luxury – something you can easily cut back on. However, before pulling your next late night study session, take a moment to think about what it may mean for your brain.
According to an article from the BBC, during the stages of deep sleep, our brains are working hard to move memories from short-term storage into long-term storage, allowing us to free up more short-term memory for the next day. If you don’t get sufficient sleep, these memories will be lost.
A common misconception is that you can reduce sleep during the week and make up for it by sleeping more during the weekend. Unfortunately, this does not work because memories need to be consolidated within 24 hours of being formed. Otherwise, they may be forgotten. (How much can an extra hour’s sleep change you?) What this means is that the things you study late at night instead of sleeping may be lost anyway, in addition to things you learned earlier during the day.
Following a period of deep sleep, your brain enters REM sleep, named after the rapid eye movements that are associated with this phase. During this stage, your body muscles are paralysed. If you have ever woken up at night and have experienced the odd sensation of being unable to move, then you have experienced this effect.
During REM sleep one of the stress-related chemicals in the brain, noradrenalin, is switched off. This is the only time during the day that this happens. “It allows us to remain calm while our brains reprocess all the experiences of the day, helping us come to terms with particularly emotional events.” (How much can an extra hour’s sleep change you?)
“We get more REM sleep in the last half of the night. Which means that if you are woken unexpectedly, your brain may not have dealt with all of your emotions – which could leave you stressed and anxious. Drinking alcohol late at night is not a good idea as it reduces your REM sleep while it is being processed in your body.” (How much can an extra hour’s sleep change you?)
Sleep is also of immense physiological importance. A study at Surrey University in the United Kingdom found that volunteers who got six and a half hours of sleep every day for a week performed much more poorly on computer tests than other volunteers who go seven and a half hours of sleep every day for a week. “They struggled with mental agility tasks when they had less sleep, but the most interesting results came from the blood tests that were run.” (How much can an extra hour’s sleep change you?)
Dr Simon Archer and his team at Surrey University were particularly interested in looking at the genes that were switched on or off depending on how much sleep the participants got.
“We found that overall there were around 500 genes that were affected,” Archer explained. “Some which were going up, and some which were going down.” (How much can an extra hour’s sleep change you?)
“What they discovered is that when the volunteers cut back from seven-and-a-half to six-and-a-half hours’ sleep a night, genes that are associated with processes like inflammation, immune response and response to stress became more active. The team also saw increases in the activity of genes associated with diabetes and risk of cancer. The reverse happened when the volunteers added an hour of sleep.” (How much can an extra hour’s sleep change you?)
So what message should you take away from this? Changing your sleep rhythm can have a major impact on your productivity and health.
Here is to hoping that we will see fewer sleep-deprived zombies after today. Happy Halloween.
Mosley, M. (2013, October 9). How much can an extra hour’s sleep change you? BBC.
Retrieved from http://www.bbc.co.uk/news/magazine-24444634.
[Untitled picture of a student sleeping]. Retrieved October 31, 2013, from: