A third of our life is spent sleeping – for a 90 year old that would mean around 33 years of sleep! Sleep is defined in psychology as: a readily reversible state of reduced responsiveness to the environment. As we sleep and shut our eyes we experience the suspension of our consciousness, and reduced muscle and brain activity.
Sleep is defined in psychology as: a readily reversible state of reduced responsiveness to the environment. As we sleep and shut our eyes we experience the suspension of our consciousness, as well as reduced muscle and brain activity.
We all need to sleep, and fighting the urge to sleep is a battle that is always eventually lost. Even attempting to avoid sleep for prolonged periods causes “micro-sleeps” whereby you experience mini-sleeps mixed with wakefulness, which may sometimes even happen during dangerous situations such as driving! Rats who are deprived for long periods without sleep eventually die, and humans have also shown this to be the case after prolonged sleep deprivation.
For it to be such an unavoidable part of our lives, surely it must have a hugely important purpose?
Why do we sleep?
Scientists have offered various theories as to why we sleep, ranging from the following:
- To help our body cells grow and heal from damage
- To allow the brain to clear out waste products and toxins
- To allow us to be able to focus and function the next day by helping us sort and clear up room to make new memories
- To allow us to conserve our energy during the night where we are less likely to be productive
Essentially the theories point out that having a few hours every night where the body can rest, enables a variety of beneficial functions crucial to our survival to take place.
Intriguingly, as varied as the above theories are, Islamic teachings about sleep go hand in hand with the body of literature contained in psychology, which becomes apparent once you look closer at what has been uncovered so far about the purpose of sleep.
Rest and Recovery
Rest and recovery are commonly cited reasons for sleep. The opposite of rested is “tired”, a state which is usually followed after long periods of wakefulness, and so sleep is seen as a “cure” for this tiredness.
And We made your sleep to be rest (to you) [Quran: 78.9]
The Quran states it quite simply – sleep enables rest, and it is within this rest that recovery and recuperative functions such growth, healing, and waste clearance can occur.
Cellular growth has been linked to sleep, for example babies and teenagers evidently sleep more, which correlates with their higher rates of growth. Cell repair also occurs during sleep as well as the production of white blood cells, making you less likely to catch a cold when you are well rested thus improving your immune system. The impact on physical health is clear when you look the links between sleep deprivation and diabetes, high blood pressure, weight gain, and heart disease. Essentially sleep is not just rest, but vital rest.
Islam makes it undeniably clear that sleep is important for you. Even though Ibaadah (worship) is so pivotal to the religion – the only religion to request timely prayers at least 5 times a day – sleep is still promoted keenly: consider the following hadith (prophetic saying):
The Prophet Muhammad (peace be upon him) once asked a companion: “(Is it true) that you fast all day and stand in prayer all night?” The companion replied that the report was indeed true. The Prophet then said: “Do not do that! Observe the fast sometimes and also leave (it) at other times. Stand up for prayer at night and also sleep at night. Your body has a right over you, your eyes have a right over you and your wife has a right over you.” [Hadith: Bukhari]
With the prophetic reminder that “your body has a right over you” Islam promotes a health-conscious, body-positive outlook, whereby the nightly prayers should not disregard looking after our health. Essentially, looking after our health (i.e. by sleeping and giving our body its right to have rest, avoiding destructive intoxicants etc.) is a part of Islam, since being unwell can get in the way of earning good deeds whether it be through being able to pray, fast, or even to be dutiful to our families and communities.
“Let not your own hands contribute to your destruction. And do good; indeed, Allah loves those who do good.” [Quran: 2.195]
Thus by asking us to pray, but also consider the rights our body has over us, is a direct command to give our body what it requires for it to be healthy and well: sleep. Considering the destructive aspects of sleep deprivation, it is no wonder such advice is promoted.
Moreover, psychologists and neuroscientists have uncovered the workings of the glymphatic system – a system which allows the clearance of waste from our brains. The brain floats in a watery substance called CSF (cerebrospinal fluid), a fluid which can have a build of waste products from long hours of having a wakeful brain. One of these waste build ups is a protein called amyloid beta, which is in extremely high concentrations in those who have Alzheimer’s disease.
The glymphatic system allows the drainage of waste products such as amyloid beta from the CSF, a process which is found to increase in rate during sleep (Xie et al. 2013).
What is profoundly fascinating is that the Prophet recommended sleeping on the right as the best position for sleep:
The Prophet said: “When any one of you goes to bed, let him clear his bed by hitting it with his garment, for he does not know what may have come onto it. Then let him lie down on his right side…” [Hadith: Bukhari & Muslim]
This advice is reflected in further recent findings of the glymphatic system, whereby scientists uncovered that sleeping in the lateral position is the best position for this waste clearance process (Beneviste et al. 2015?). Their findings supported that this position was most efficient in aiding glymphatic transport, compared to lying on the back or lying on the stomach.
In fact, lying on the stomach is a position disliked in prophetic narrations:
Narrated Abu Hurairah that the Prophet saw someone sleeping on his stomach and he said, “This is a reclining that is not loved by Allah” [Hadith]
Indeed, literature points to the detriment of sleeping in such a frontward position – cot death and sudden infact death syndrome has been linked to sleeping in this position.
It is a generally not recommended to sleep on the stomach even for adults as this position puts stress on your back and spine.
Nevertheless, sleep allows us to rest, recover, clean out waste. However there are other findings in psychology that point to the role sleep plays with assisting our cognition, emotions, memories and our minds.
Mind and Memory
The mind remains an elusive mystery, but it is undebatable that the brain houses it. Thus sleeping is said to aid the mind. This includes a variety of factors such as:
- improving mood
- making you less irritable
- increases motivation
- increases concentration and memory
- increases creativity
- increases productivity
- increases ability to make decisions
- decreases risk of depression
In regards to depression, it has been consistently found that there is a clear link between mental health and sleep, whereby many mental health issues arose due to or partially due to sleep deprivation. Alternatively sleep deprivation can make current mental health problems worse.
Being devoid of sleep has the following impact on the mind:
- increase in negative thoughts
- reduced ability to deal with day to day life, thus increasing anxiety
- low mood
- can lead to psychotic episodes/hallucinations
Essentially this ties into how looking after our health is an extremely important aspect of Islam, and the beneficial aspects of a good night of sleep is clearly echoed metaphorically in the Quran.
And He it is Who makes the night as a robe for you; and sleep as repose, and makes the day (as if) a Resurrection. [Quran: 25.47]
Moreover sleeping well aids with focus and concentration. Our brain is made up of billions of cells called nerves. Nerves are connected by small gaps called synapses. As we go through life new synapses are made between nerve cells, almost like an intricate train station map connecting different memories and bits of information.
As we go about our day-to-day lives, you can imagine the amount of information we would take in during a day, ranging from new faces to remembering what we ate for breakfast. All this information would be integrated into our synapses and nerves.
However our brain needs to digest and sort through information at the end of each day. You most likely remember what you had for breakfast today, but can you remember what you had for breakfast 2 years and 4 months ago? (And those of you who eat the exact same thing every day – that’s cheating!) “Memory cleaning” can take place when we sleep, similar to computers, making room for new memories to form. In fact rats synapses (the gaps between our brain cells) were found to be 18% smaller in size after sleeping compared to just before sleeping, a process called pruning where we can get rid of information we do not need so that our minds are not clogged up for the new day. However why we forget useful information is a whole different story (men and wedding anniversaries!)
Thus the ability to focus, and be mindful of what we are doing therefore cannot be possible without having slept. A prophetic narration conveys this whereby the prophet says:
“If any one of you feels drowsy when praying, let him sleep so that (when he gets up) he knows what he is reciting.” [Hadith, Bukhari]
And withholding sleep from ourselves affects the ability to focus and achieve the level of submissiveness required of salah (prayer):
“Successful indeed are the believers. Those who offer their Salah (prayers) with all solemnity and full submissiveness” [Quran 23: 1–2]
It may seem obvious to every single one of us, but nevertheless studies have shown how after a good night’s sleep the brain is more electrically responsive at the start of the day upon waking, rather at the end after the brain is spent.
The mere fact that Islam states that prayer made whilst drowsy is not worth offering compared to prayer offered after having slept adequately gives a nod to its deep acknowledgement of mindfulness. Islam means to be submissive to Allah, and for this to occur, for the mind to truly be submissive and focused and capable, sleep is essential. To advise to be able to pray so “he knows what he is reciting” draws upon the Islamic importance of being genuine, not just in action but also in mind.
So sleep has vital functions for our health, body and mind. But why does sleep occur mostly during the night?
The Day-Night Dilemma
Our body clocks align with night and day, so (usually and ideally) we sleep when it is dark and we are awake during the daylight hours. This is a natural rhythm scientists call the circadian rhythm. It is why we are able to sometimes wake up just before the alarm goes off!
If there is light present, it has an inhibitory effect on the systems of the brain involved in making us feel sleepy. That is, the presence of light stops the pineal gland from releasing melatonin, the hormone that causes sleepiness. This goes a long way in explaining why it is harder to fall asleep in broad daylight and we need to draw the curtains or wear blindfolds.
However if there is no light, i.e. darkness, this has a stimulatory effect and causes the SCN (suprachiasmatic nucleus) to allow the pineal gland to release the melatonin and thus allows us to feel drowsy and sleep. By having a regular sleeping pattern enables the circadian rhythm to function and remain intact, and it explains why we struggle with jet lag when we fly abroad as our circadian rhythms are disrupted. Often those who struggle with long term insomnia are prescribed over-the-counter melatonin to take.
This need for darkness and protection of the circadian rhythms is recognized in prophetic narrations:
“Put out lamps when you go to bed, shut the doors, and cover water and food containers” [Hadith: Bukhari]
However recent research has shed even more light (excuse the pun) on how sleeping during the night is not just an operational mechanism, but beneficial to us and how sleeping only during sunlight is potentially harmful. An experiment with 134 mice demonstrated that when they experienced no darkness for 6 months it led to loss of strength, and weakness of bones and an impact on the immune system similar to when there is an infection. The good news is, when these mice were allowed to have darkness again these problems were very quickly reversed.
Allah alludes to the detrimental impact of having continuous light in the Quran, pointing out that having nighttime for rest is something to be grateful for:
“Say: Do you see if Allah were to make the day to continue incessantly on you till the day of Resurrection, who is the god besides Allah that could bring you the night in which you take rest? Do you not then see?” [Quran: 28.72]
He it is Who made for you the night that you might rest in it, and the day giving light; most surely there are signs in it for a people who would hear. [Quran: 10.67]
Psychologists have used these findings about day-night sleep cycles to provide advice to those who have disrupted sleep patterns for example shift workers who often have to work during nights. Some shift workers are prescribed over-the-counter melatonin to take, others are told to try and have some days where they are able to sleep during the night.
The Brother of Death
The first dua (supplication) the Prophet would say upon waking was:
Alḥamdu lillaahil ladhee aḥyaanaa ba‛da maa amaatanaa wa ilayhin-nushoor:
“All praise is due to Allah, who has given us life after death, and to Him is the return”
In Islam there is an understanding that whilst we sleep, our souls return to God momentarily, and thus upon waking we are grateful to have returned to life.
“It is He, Who takes your souls by night (when you are asleep), and has knowledge of all that you have done by day” [Quran: 6:60].
“It is Allah Who takes away the souls at the time of their death, and those that die not during their sleep. He keeps those (souls) for which He has ordained death and sends the rest for a term appointed. Verily, in this are signs for a people who think deeply” [Quran 39:42].
Psychology may not have reached a point where it can acknowledge the soul or even the existence of it. However Al Ghazali, a Muslim Philosopher once queried: how can it be that man can fall every night into a state where he sees images that are not there, explores a world without leaving his position, and wakes up refreshed.
Essentially, dreams may contain more about the psyche than we currently know.
Look out for our Dreams article coming soon!
By Murrur (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons
‘S S’ http://www.freeimages.com/photographer/sskies-41129