Want to be more productive? Get sufficient sleep.

Sufficient sleep is so important. If you are someone who sacrifices sleep in order to get more done, it’s time to rethink that strategy. In this article, we explore the immense benefits of sleep on cognitive functions such as learning, problem-solving, memory and creativity. We will also look at the detrimental effects of poor sleep on productivity.

We used to regard sleep simply as a state of rest. This is when our mind and body run at their lowest level. Our energy recharges for the day ahead. In the past few decades, however, we have discovered that sleep is and does so very much more.

The manifold benefits of sleep on physical and mental health are the subject of numerous books, articles and research papers. But for the purpose of our focus on productivity, let’s look at the effects of sleep in just one area: cognitive functions.

Sleep is NOT the enemy of productivity

In the course of a day, we receive information, use reasoning, make decisions, solve problems and so on. Such mental processes are a large part of life. This is certainly a major part of being an effective worker at skilled jobs.  However, in our desire to be effective and productive, we are ironically sabotaging ourselves by skimping on a crucial and necessary resource: sleep. Numerous studies have shown that we rack up huge losses when we don’t get enough sleep.

This study found that insufficient sleep causes up to US$680 billion in losses each year across five OECD countries. A Casper-Gallup study from 2022 showed that poor sleep in workers in the US resulted in an estimated US$44.6 billion in lost productivity each year. In another study, subjects who reported getting 5-6 hours experienced 19% more productivity loss. Those who got less than 5 hours of sleep experienced 29% more productivity loss. This compares to those who regularly get 7-8 hours of sleep.

Sufficient sleep strengthens memory and boosts learning

Moving on from the scary statistics, let’s look at how sleep supports cognitive performance.

We kick things off with the interaction between sleep and memory. Sleep helps you retain information, thereby making you learn better. Scientists have found that sleep improves the ability to learn, memorise, retain and recall knowledge. Many studies have unveiled the complex relationship between sleep and memory. They demonstrate that sleep helps you strengthen the memories you’ve formed in the course of the day, as well as link new memories to earlier ones. 

One study from MIT, for example, found a strong relationship between students’ grades and how much sleep they had. The study was done over one semester. It was found that “overall course grades for students averaging six-and-a-half hours of sleep were down 50%”. This is compared with students who had just one hour more sleep on average. The study also showed that getting just one good night’s sleep before the big day of a test doesn’t work. Students needed to get sufficient sleep consistently, especially on the days when learning was happening.

Sufficient sleep supports every step of the learning process

There are three steps to the process of learning: acquisition, consolidation and recall. Acquisition is when the brain receives information. Consolidation is when the brain chooses which memories or information to keep and which to discard. Retained information moves into stable and long-term storage. This process can take hours or days. The third process – recall – is when the brain accesses and makes use of stored information, bringing out those stored memories.

Impact on learning

Inadequate sleep negatively affects all three steps in the learning process. Acquisition and recall obviously take a hit as you are less able to focus when sleep-deprived. You struggle to remember what occurred previously. In the area of consolidation, the effects of poor sleep are more profound. Your ability to consolidate factual information (the capital of Fiji or where you parked your car) and procedural memories (playing the piano or riding a bicycle) is significantly hampered.

Yet another study showed that sleep improved the ability to learn. This time, a group of adults were subjected to two rigorous learning sessions at noon and 6 pm. One group had the opportunity to nap after the first session while the other stayed awake. At 6 pm, both groups were subjected to another round of intensive learning, which required them to memorise a new set of facts. The group that napped performed markedly better, with a 20% advantage. Sleep was able to restore and refresh the brain’s capacity to learn.

“Making up” myth

Unfortunately, there is no way to make up for a shortage of sleep. You need good and sufficient sleep before learning so that you’re able to absorb the information and good sleep after so that you can consolidate and better retain the information. You lose learning opportunities on a particular day when you have insufficient sleep.

Unleashes creativity and problem-solving

You may have heard about people who are puzzled over a problem for a time, go to sleep, and then wake to an “a-ha!” moment. Perhaps you’ve even experienced it yourself. Thinkers, artists and poets have long realised the link between sleep and creativity or problem-solving. Scientists are now trying to unravel this mystery.

Problem-solving in REM sleep

In one study, scientists tested 16 participants with anagrams (scrambled words, for example, OSEOG = GOOSE). Each anagram had only one correct solution. The participants were woken up four times at night to solve these puzzles. Twice during NREM sleep and twice during REM sleep. The participants who woke up from REM sleep were able to solve 15% to 35% more puzzles compared with awakenings from NREM sleep or when awake during the day.

If you’ve heard of the “falling asleep while holding a spoon” method, well, researchers are unpacking the science behind this trick. Visionaries like Thomas Edison and Salvador Dali supposedly practised this. The idea was to draw on the creative power that emerges in that brief, semi-conscious state between wakefulness and sound sleep. 

Ideal for creative ideation

Recent research has proven that the brief period when drifting off to sleep may be “an ideal brain state for creative ideation”. A 2021 study found that participants who woke from that twilight zone of sleep onset were three times as likely to solve mathematical problems than remaining awake. (The effects are lost on participants who fell into a deeper sleep state)

A 2023 study found that creativity scores were higher in participants who were instructed to drift off to sleep than in participants who were told to remain awake. Interestingly, you can even direct your subconscious thoughts during this creative sweet spot, what the researchers called “targeted dream incubation”. The researchers introduced specific themes into dreams, specifically, trees. When awoken, the participants who were given cues about trees had even higher creativity scores than those who napped but were not given cues about trees. The “tree” group showed enhanced creative performance on all tasks related to the incubated theme.

Sufficient sleep is the way to better performance

In our fast-paced, competitive and industrialised world, we seem fond of measuring ourselves by how much we produce and consume. We seem to almost pride ourselves on being busy busy busy. We push sleep to the margins. This is to the point of being associated with laziness or indolence.

It’s time to rethink our relationship with sleep. We must accept that it is a non-negotiable requirement for health and well-being, just like food and water. Your mind and body need to be at their optimal states to produce and perform as best you can. And that won’t happen if you shortchange yourself of sleep.  

If you’d like to improve your time management or find ways to carve out personal time from your schedule, let us help. As qualified psychologists and coaches, we have the tools and know-how to guide you toward realising your best self. Sleep on it, then get in touch with us.