The mental benefits of sleep – what you will learn in this article
Sleep improves productivity, performance and attention – 10 days of 6 hours sleep impairs concentration levels by the same amount as no sleep for 24 hours straight!
Sleep improves learning and memory consolidation – Memories move from the short-term storage bank to the long-term memory vault during NREM sleep, clearing storage for more short-term memories and consolidating long-term memories.
Sleep spurs creativity – REM sleep facilitates the development of general knowledge, novelty and creativity.
Sleep reduces the chance of mental illness, stress & depression – Sleep deprivation results in us reverting back to our primitive behaviour of uncontrolled reactivity which becomes more intense both on the positive and negative ends of the emotional spectrum.
Sleep improves productivity, performance and attention
We can explore the science of sleep’s impact on productivity and performance, but why bother?
You only need to think back to when you had to complete a task after a poor night’s sleep.
The chances are you were lethargic, slow, disinterested, inattentive and probably a mixture of all those feelings.
It’s easier for us focus, refocus (after a distraction) and make decisions quickly, easily, and confidently.
For those of you who like scientific proof, a study published by the National Center for Biotechnology Info (NCBI) found that:
This was also true of anaesthesia trainees:
This is just one of many studies that proves sleep deprivation impacts on performance.
Sleep expert, Dr Matthew Walker details a study in his book which may be extremely relevant to you…
The study tested concentration levels of individuals who were restricted to 8 hours sleep per night, 6 hours, 4 hours and no sleep at all.
It was found that 10 days of 6 hours sleep (which many of you may be subject to!), impairs performance by the same amount as no sleep for 24 hours straight!
The number of microsleeps (lapses in concentration) increase by 400 percent!
The worrying thing is, this deterioration in performance doesn’t appear to reduce as time goes on.
According to the findings: “All signs suggested that if the experiment had continued, the performance deterioration would continue to build up over weeks or months.”
No matter how hard you try, you’re not going to perform well if you’re tired! Just ask Tom…
Sleep improves learning and memory consolidation
Sleeping both before and after learning can have significant advantages to your cognitive development and memory consolidation.
Dr Matthew Walker and his team compared two groups of people in an attempt to confirm this – those that took a ninety-minute siesta at noon each day and those that browsed the internet or played board games instead.
He tested both groups, before and after noon, with a challenging memory test (learning one hundred face-name pairs and later matching them).
The performance of both groups before noon were comparable, as you would expect, but after noon, the group that had a ninety-minute siesta performed twenty percent better than those who didn’t.
Analysing the electrical brainwaves, Walker and his team found that “the memory refreshment was related to lighter, stage 2 NREM sleep, and specifically the short, powerful bursts of electrical activity called sleep spindles.”
Sleep spindles appear to be responsible for moving memories from the brain’s short-term memory bank (hippocampus) to the long-term memory vault (cortex).
The more sleep spindles an individual has at night, the greater learning ability they will have the next morning because transferring short-term memories to the long-term vault leaves space in the hippocampus for new memories.
This is why older people find it more difficult to recall short-term memories. They are unable to generate sleep spindles at the same rate as a younger person so they can’t clear out their short-term memory bank quick enough to cram in new facts.
The transfer of memories into long-term storage is also important here.
Many studies have proven that, although sleep spindles play a part in transferring memories to the brain’s long-term storage facility, memory consolidation is most significant during deep, NREM sleep.
Slow brainwaves carrying information from the hippocampus to the cortex can offer a 20%-40% increase in memory retention when compared to being awake.
So for you students who think all-night cramming sessions are appropriate for your success, think again!
This has also been attributed to why older people struggle with memory retention. Older individuals usually find it difficult to get a full night of undisturbed deep sleep in comparison to their younger counterparts.
Sleep spurs creativity
REM, the active or dreaming stage of sleep, is where associations are made between your entire bank of memories; aiding general knowledge, novelty and creativity.
It’s the stage you’re relishing in when you wake up with that great idea!
Albert Einstein was a famous proponent of both creativity and sleep! Maybe this is the stage he relished in!
We check out Einstein’s sleeping habits in: Napping Techniques Explained | How To Nap Like Your Heroes.
A real-life example of an individual waking to create during a spell of REM sleep is Keith Higgs.
When we spoke to him on a recent podcast, he mentioned waking up early in the morning to write sections of his books.
What do you think… a creative result of REM sleep or a message from the Universe?…
Sleep reduces the chance of mental illness, stress & depression
There are no major psychiatric conditions where a sufferer sleeps normally – Fact!
No matter what mental illness you consider – stress, depression, anxiety, Alzheimer’s, schizophrenia, suicidality, post-traumatic stress disorder (PTSD) or bipolar – lack of sleep always appears to be present.
Most believe that lack of sleep is a consequence of mental illness, but can mental illness be a consequence of restricted sleep?
To answer this, I must refer to the bible of sleep for the common man – Matthew Walker’s Why We Sleep.
In chapter 7 of his book, Walker describes how his team analysed two groups of healthy adults. One which stayed awake all night and one which had a full night of normal sleep.
Both groups were shown a range of pictures with differing emotional contexts.
It was found that the emotional reactivity of those who were sleep deprived was well over 60 percent more vigorous than those who had a normal night’s sleep (measured through MRI testing).
Such study was replicated by a team in Japan, with similar results.
It seems to be heavily documented in scientific literature that sleep deprivation impacts heavily upon our emotions and mental health:
- The Neuroprotective Aspects of Sleep
- Sleep found to repair and reorganize the brain
- Sleep and mental health
- Sleep and Circadian Rhythm Disruption in Social Jetlag and Mental Illness
Science aside, common sense suggests that our emotions run wild after a sleepless night.
Have you ever heard a parent say “he’s tired” when their baby is wailing in the supermarket, or someone say “I was tired” as an excuse for lashing out or making a rash decision?
How does a lack of sleep lead to heightened emotional activity?
When we sleep, our bodies re-balance chemical and hormone levels.
If we deprive ourselves of sleep, our bodies cannot take advantage of this chemical re-balance and our prefrontal cortex (the rational thinking brain) loses its strong connection with the amygdala (the emotional brain) and the striatum (the pleasure centre of the brain)
This means that our rational brain loses control of our emotional brain, allowing it to run riot!
We revert to our primitive behaviour of uncontrolled reactivity which is becomes more intense both on the positive and negative ends of the emotional spectrum.
Why is this relevant to you?
Large swings in emotions from negative to positive, and back again, can be extremely detrimental for your mental health.
It is also extremely important that you are aware of this for the benefit of your family and friends; especially your children during a period where their brains are maturing – a susceptible time for developing psychiatric disorders.
Extreme negative moods can often lead to feelings of worthlessness, depression, anxiety and suicidal thoughts. Extreme positive moods can lead to addiction, rash decision making and unnecessary risk-taking.
Bipolar disorder is especially relevant here as this is where individuals vacillate between periods of mania (euphoric, over-reactive behaviour) and depression (severe sadness and despondency) – hence it’s previous name ‘manic depression.’
This isn’t to say that sleep is the reason for mental illness but it’s clear that, from scientific evidence and generally observing life around us, sleep deprivation influences our emotional stability and therefore the quality of our mental health, just as much as the quality of our mental health impacts upon the virtue of our sleep.
To maintain a healthy mind, sleep must be high on your priorities list.