Scientists confirm lack of sleep makes you dumber
According to new findings published in Nature Communications, when we fail to get a decent amount of restful sleep, this impedes the connective neurons that assist us with memory and learning.
Now, to anyone who’s made the mistake of an all-night Netflix-binge before a huge day at work, the impact fatigue has on your ability to remember even a simple coffee order seems rather obvious.
But apparently the connection between sleep deprivation and total brain fog has been difficult to prove until today.
To reach this breakthrough, Dr Christoph Nissen from the University Medical Centre Freiburg in Germany and a team of researchers compared the brain activity of 20 participants after one night of sleep deprivation to a second group that were well rested.
Tired bodies, tired brains
Their results showed that the strength of the pulse needed to produce a muscle response in the left hand was much lower for the participants who were fatigued. This, Nissen’s claims, suggests brain excitability was higher in people who didn’t get a good night’s sleep. Which kind of explains why some of us have such a short fuse when we’re tired.
Secondly, they also found that people who didn’t get enough sleep had reduced levels of BDNF in their blood samples – a signalling molecule known to regulate synaptic plasticity aka learning and information recall. To hammer this result home, they had the troupe of tired volunteers then perform a word-pair memory task. They didn’t do well.
But aside from the obvious – which is, we all need to get more sleep in order to function at our very best – the research does pose an interesting question: does quality of sleep count higher than quantity of sleep? And are they same thing?
Quality, not just quantity
According to Dr Nissen, they’re (thankfully) not.
“There is certainly a difference,” Dr Nissen tells The Juice Daily.
“Sleep researchers use the expression ‘sleep continuity’, which refers to the duration of sleep and the amount of time awake during sleep, and the expression ‘sleep architecture’, which refers to the distribution of sleep stages, including light sleep stages N1 and N2 and the deep sleep stage N3 (also referred to as slow wave sleep).
“These sleep stages are referred to as Non REM sleep because they substantially differ from the specific sleep stage of REM sleep. Both sleep continuity and architecture are supposed to be critically important for the experience of restorative sleep.”
Back in 1997, scientists from the Department of Psychology at Bradley University, Illinois, attempted to assess the difference between quality and quantity sleep.
Splitting subjects into two groups, each group completed a seven day sleep log and filled out a series of surveys that looked at their overall feelings of health, well-being, and sleepiness.
In those who experienced an average of seven hours a night, average sleep quality “was better related to health, affect balance, satisfaction with life, and feelings of tension, depression, anger, fatigue, and confusion than average sleep quantity”. But interestingly, the average sleep quality was better related to sleepiness – or in other words, people who went to bed tired actually experienced a better night’s sleep.
But the result of this study actually suggests that when do talk about achieving an optimum night’s rest, the quality and quantity are as equally important. Or in other words, six hours of unbroken sleep is probably going to be better for you than 10 hours broken up by regularly checking to see if anyone’s liked your new profile pic on Facebook.
But when we think about it like that, we seem to come back to the age-old question of how much sleep is the right amount. Something that Dr Nissen concedes is not yet entirely known.
“This is a good question and the answer is – I don’t know (and I suppose nobody really knows),” says Dr Nissen.
“What we know is that most of the deep sleep phases (slow wave sleep) occur within the first hours of sleep. For instance, the absolute duration of slow wave sleep is more or less the same if you sleep five or nine hours (the duration spend in light sleep stages and REM sleep makes the difference). Slow wave sleep appears to be most important for synaptic connectivity and one might think that, with regard to plasticity, some hours (e.g. five hours) might be enough. But, first we don’t know if this is true and second, we might miss other functions of sleep. From an evolutionary perspective (evolution optimized a lot), one might think that about seven to eight hours is ideal for humans.”
Tips for a good sleep
But assuming you’re a quality over quantity fan such as myself, here are a few tricks to better your REM and get a deeper, if not longer, sleep:
- Go to bed at the same time, each night. Your body responds to cycles, and this helps train the brain to know when it’s time to shut down.
- Switch it off – your phone, your laptop, your Fitbit notifications. All off. When it’s bed time, make a conscientious effort to rid yourself of distraction.
- Switch TV time for reading (an actual book) – reading helps relax the body.
- Cut back on the caffeine. After lunch, change over to tea. And in the evening, drink a cup of chamomile tea. Chamomile increases glycine in the body, which acts as a mild sedative and calms the nerves.
- Burn some lavender oil – lavender is a known relaxant and can promote a more restful atmosphere. And it just smells nice.
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