Want to learn something?... You’d better sleep on it.

First, an admission, I love to sleep. Any opportunity to have a quick nap and I am there. So, imagine my delight when I actually started to understand how incredibly beneficial sleep was to our general health and well-being. Getting 8 hours of sleep each night is said to be the benchmark of a good night’s rest and it is said that creating a great bedtime routine can protect us from all kinds of ills. Sleep has also been shown to be important to cognitive function, especially learning. Learning is consolidated by sleep. During our times of slumber, the brain processes and integrates new information and experiences from the day. This helps to reinforce memories and make connections between new and existing knowledge. Good quality sleep also improves focus, attention, and problem-solving abilities. Thus allowing individuals to better retain information and perform better.

Many of us think that when we sleep our brain becomes silent, all the little neurons say goodnight and switch themselves off. It turns out that this couldn’t be further from the truth. 

Whilst asleep, the brain takes part in a perfectly choreographed movement of different states and brain waves. There are two types of sleep, N(non)REM and REM. The NREM, or slow wave sleep (Maquet 2001), consists of brainwaves that are different to those we notice when we are wakeful. Matthew Walker, the eminent sleep scientist, in his epic book Why We Sleep (2017) describes the brain when engaged in NREM sleep as a chorus of unity; “When we are in NREM sleep all the brain areas are as one, it’s like the fans in a football stadium all singing in unison”, and that is what we see on an EEG (Electroencephalogram), it’s like all the different brain areas are being moved along together with the tide. Whereas REM, or paradoxical sleep, is like the stadium at half time, noisy, with everyone talking at different times, about different things. The EEG of someone in REM sleep is very similar to that of someone who is wide awake. 

Typically, we have 3 stages of NREM sleep and 1 of REM sleep, with REM sleep always being the last. Each different stage of sleep has a different function that affects the brain. Throughout the night the we cycle through these different stages several times. So what some people consider as a waste of hours in the day is, in fact, absolutely vital to learning, memory and optimal performance.

According to Feld & Born (2019); “Sleep is essential for memory formation. Active system consolidation maintains that memory traces that are initially stored in a transient store, such as the hippocampus, are gradually redistributed towards more permanent storage sites, such as the cortex during sleep replay”. What this tells us is that those weak memories, that the hippocampus so frailly hangs on to, are fortified and transferred during sleep. They also highlight that memory encoding, retrieval and consolidation are all strengthened by the sleep process. Gonzalez et al (2020) in a study called “Can sleep protect memories from catastrophic forgetting?” state that; “Training a new memory interfered with previously learned old memories leading to degradation and forgetting of the old memory traces. However, stimulating sleep after new learning reversed the damage and enhanced old and new memories”. It would appear that modern science is really highlighting the benefits of a good night’s sleep.

Sleeping after a learning event is seen as vital, however, Matt Walker, considers sleeping before a learning event just as important. Throughout our waking ours we are constantly making decisions and acquiring new knowledge. Some of this knowledge is fairly useless to us, like the registration plate of the cars that pass us on the motorway, or whether the horse is in a particular part of the field. Sleep helps sort this, getting rid of all the memories that we don’t require an consolidating the ones that we do. It is almost like sleep cleans the chalkboard ready for the next day.

Many of the functions of sleep are still unknown, however, science is very quickly unravelling this mystery and with each study that is published the importance of good quality sleep is amplified. Sleep is an active part of our life; it should never be seen as a passive event.

As L&D professionals we need to consider sleep as one of the main factors to learning and memory consolidation. We should allow for sleep at every opportunity. One off training interventions are simply not good enough. What can we do to support a sleep based learning strategy? Some options may be;

Flip the classroom. Send any learning material as a pre read, about a week before the learning intervention. This will stimulate neural pathways, which will then be strengthened by sleep and make the learning more efficient.

Spaced learning is a great method to leverage sleep as a learning superpower. Shorter sessions spaced over a period of time is great for attention and memory consolidation.

Carry out knowledge checks at spaced intervals also. Do knowledge checks at; 10 minutes, 24 hours, 1 week, 4 weeks after the learning event. This not only stimulates forced recall but gives the opportunity to consolidate this recall over a longer period of time.

However, is good quality sleep becoming harder to achieve? We now know more about sleep than we ever have, but it seems that sleep is still seen as a luxury by a lot of people. We live in a world of 24hr connectivity, social media, and round the clock TV entertainment and we find it difficult to disconnect.  We may well have a problem of epidemic proportions.  Adults are hooked to their mobile devices and consistently use them as part of their sleep routine. These digital crack pipes are incredibly addictive and give us no support with regards to good quality sleep. The blue light emitted from the screen stimulates the brain and starts to alter the circadian rhythm. 

A lot of the discussion around this topic is still opinion based, however, some of the pioneering studies around the excessive use of mobile devices have tentatively shown that they do indeed interfere with our neural pathways, rewiring the brain, and making good quality sleep harder to come by. In one study, Small et al (2022) state; “Potential harmful effects of extensive screen time and technology use include heightened attention-deficit symptoms, impaired emotional and social intelligence, technology addiction, social isolation, impaired brain development, and disrupted sleep”. In another, Limone & Toto - (2021) state; “The increased usage can have effects on brain functioning that will compromise sleep and cognitive abilities and develop risk for certain mental illnesses including, but not limited to, depression, anxiety, Alzheimer’s disease, and attention-deficit/hyperactive disorder (ADHD)”.  

What we don’t know just yet is just how much the altering of sleep states is affecting the human population. However, a prediction might be that our ability to learn will be greatly affected and we will rely more and more on digital devices to store our knowledge.  A vicious cycle. If you think this could be problem for yourself or anyone in your family, have device free zones in the house. Make the lounge and the bedroom off-limits to mobile devices and limit the time spent on social media. Create a binding contract with your family, so that if device behaviours start to re-emerge they are called out and supported by the family unit.

Science as invested a lot of time and energy studying the sleep patterns of humans and other animals. These studies have been illuminating in the context that; what we once thought of as passive event, that was lazy and a waste of hours in the day, is actually vital to human survival. Sleep has been shown to be beneficial to human performance, however it is measured.  Sleep, if we could bottle it, would be a blockbuster medication that would be a best seller the world over. Design learning interventions to leverage sleep, in other words, get your students to sleep on it. Get your 8 hours per night, avoid sleep medications, ditch the mobile device after 6pm. Most of all treat sleep the same way you would treat eating food or drinking water, as a necessity.

John Whitfield

A sleep fan.