Sleep on it

Guillaume Hansali
Guillaume Hansali
Sleep on it
Table of Contents
Table of Contents

You’re not getting enough sleep. That is a fact. But that’s not what this article is about. This time, we will be exploring a few interesting concepts about sleep while following the story of Greg, a senior sales representative working in a promotion agency in Tokyo.

You’re not getting enough sleep. That is a fact. But that’s not what this article is about.

As you may have realized by now, most of my articles are usually inspired by books that have left a strong impression on me. This article is no exception. I read “Why we sleep” from Matthew Walker more than a year ago, and I always wanted to write something about it one day.

As of today, we still don’t fully understand this incredible narcotic phenomenon that knocks us out of consciousness every night.

In his book, Walker demystifies sleep in a very simple jargon and clarifies many popular myths and misconceptions about our chronic temporary coma.

Having enjoyed writing my previous article, I thought I would try something similar but in a slightly different format.

This time, we will be exploring a few interesting concepts about sleep while following the story of Greg, a senior sales representative working in a promotion agency in Tokyo.

Day 0

Greg just couldn’t make his mind. His job had accustomed him to make decisions daily in a professional setting, but this was too personal. “Just sleep on it,” his boss Steve had told him, seeing his indecisive expression.

Sleeping on it was, however, a luxury Greg wouldn’t have in the coming days. He was scheduled to fly to New York the following day to pitch a proposal to a client prospect. The pandemic had financially hit Greg’s firm, and getting that new client on board would be a huge blessing.

Adding to the pressure of closing the deal, Greg usually gets anxious the day before he flies somewhere. The fact that he procrastinated until the last minute before getting his bags packed didn’t help. Between the polishing of a couple of PowerPoint slides, the search for his passport, and the realization that he hadn’t ironed his shirts, he wasn’t in bed until 2:00 am. That night, he dreamt that he was running in an endless airport, hearing his name called over and over as the embarkation gates were closing for departure. Calls were getting louder and louder and were now complemented with an increasingly strident beeping: beep, beep.

Greg was brutally taken out of sleep by his alarm setting off at 6:00 am. We all have experienced feeling nauseous from sleep deprivation, and that’s exactly how he felt. But that wasn’t only because of a lack of sleep. He’s never been an early bird, and 6:00 am was quite early for him. He’s constantly been told that it was due to bad sleeping habits and a lack of self-discipline and came to believe that, often feeling guilty about it.

He didn’t know that he was part of the 30% of the population that we call night owls, and if anything were to blame, that would be his genetics.

Early birds and night owls

Humans have lived in tribes for thousands of generations. Having members with different sleeping patterns, namely early birds and night owls, allowed for a shorter period of complete vulnerability during the night; with early birds sleeping between 10:00 pm and 6:00 am and night owls between 2:00 am and 10:00 am, the vulnerable period when everybody is asleep was just 4 hours per night.

Because well-balanced tribes were more likely to survive, and because families used to live generation after generation within the same tribes passing on their genes, we have kept an even distribution until today.

After a quick shower and a large cup of coffee, Greg was alert enough to make sure he didn’t forget anything. A brisk tapping on the chest pocket of his jacket confirmed he had his passport on him. He locked the door and was on his way to the airport.

Unlike in his dream, the boarding process was uneventful, and his plane took off on time. With 14 hours ahead of him, Greg thought he could try to get a couple of hours of sleep back, but the second coffee he had at the airport was starting to kick-off, and his eyes wouldn’t stay close.

Browsing through the movie selection, Greg stumbled upon a documentary on the sleeping habits of different animal species. Amused by the irony of the situation, he started watching and was stunned by how little he knew about sleep’s inner workings.


Sleep consists of different neural activity stages that form a cycle of roughly 90 minutes, repeating itself until we wake up. The two most important are the NREM phase, more commonly called deep sleep, and the REM phase, which we associate with dreaming.

REM stands for rapid eye movement, from the observation that during that phase, our eyes move intensively under our closed eyelids. NREM simply stands for Non-rapid eye movement. As Matthew Walker says it himself in his book, sleep scientists are not very creative with naming.

During NREM sleep, our consciousness is completely disconnected while our brain does a lot of data processing. Consciousness comes back online during REM sleep, and our brain becomes super active; we regain awareness and the notion of time, and we can literally feel and think as if we were awake.

As the virtual world created by our mind is indistinguishable from reality in terms of perception (our senses are all connected to our brain, after all), our muscles are deactivated so that we don’t act out our dream experiences.

Do all animals share the same sleeping mechanisms? Not quite.

Birds don’t have REM sleep, most likely so that they don’t fall off a tree from muscle paralysis. Dolphins, too, despite being mammals, do not enjoy the pleasure of dreaming, as they need to keep swimming to breathe. How can they sleep at all, you may ask? Half their brain at a time! Yes, they have developed the ability to have half of their brain asleep while the other half is still active. How cool is that? Just imagine how convenient that would be!

How about apes? They do have REM sleep, but in smaller proportions compared to humans. Scientists believe that this evolution resulted from humans leaving the trees to live on the plain instead. Sleeping firmly on the ground would have made it safer for us to dream for more extended periods.

Day 1

Greg woke up shaken by the plane touching the ground. He had barely slept. “It’s going to be a long day,” he told himself, grabbing his bag and leaving the plane. Indeed, a long day it would be. When Greg left the airport, en route to the local office, it was barely 9:00 am New York’s time, but his internal clock was approaching bedtime.

Melatonin and adenosine

When it comes to sleep, we often hear about melatonin. It’s a hormone produced by the pineal gland in response to darkness. It reduces our awareness, thus facilitating sleep. It also helps with the calibration of our circadian rhythm to make sure we feel sleepy at the right time of the day.

But melatonin is not alone in the sleep facilitating division. We also produce a molecule called adenosine as a byproduct of energy consumption throughout the day. The more active we are, the more adenosine gets produced. When its concentration in our bloodstream reaches a certain threshold, it starts interacting with specific cell receptors, inhibiting neural activity and causing drowsiness. This drowsiness is commonly called sleep pressure.

There is a fundamental difference between melatonin and adenosine. Melatonin is produced only when it’s dark, so we stop making it during the day. Adenosine, on the other hand, needs to be processed. Otherwise, it stays in our bloodstream. And the only way to process it? You guessed well, sleep!

When we do an all-nighter, we do produce melatonin during the night, which makes us sleepy, but once the sun is up again the following day, its effects are suppressed. Adenosine, however, would have been building up during the night on top of what we would have produced the day before. That “sleep pressure” is what makes us feel miserable the day after an all-nighter.

Caffeine to-the-rescue

How do you keep awake after a sleepless night? Coffee, of course! Coffee contains high concentrations of caffeine, a molecule that seems to have many stimulant properties on us, most notably, its ability to keep us awake. How does it do that? Well, it very conveniently attaches itself to the same cell receptors that adenosine interacts with, blocking its effects as a result.

It is just temporary, however. Caffeine doesn’t remove adenosine from our bloodstream, so once it wears off, adenosine will kickback even more strongly, as its concentration would have increased in the meantime.

Back to Greg. A series of preparation meetings with the local team and copious amounts of coffee kept him awake throughout the day.

The first meeting with the client went more or less as planned, and despite a few sleepiness attacks, Greg’s delivery of the presentation was flawless. While most of the audience seemed enthusiastic about what had been presented to them, one person, the CEO, seemed unimpressed. He asked a few unexpected questions about numbers to which Greg wasn’t able to answer. The client agreed to have a follow-up meeting the next day.

Greg called the local team and shared with them the questions from the CEO. They offered him to do a meeting right away, but Greg felt it wouldn’t have been very productive in his current state of sleep deprivation. They agreed to go over the numbers together the following morning.

Jet lagged

Checking in his hotel, Greg only had one thing in mind: crashing into the bed and giving in to sleep pressure. However, while unpacking his belongings, he weirdly started to feel more alert. It was 7 pm in New York, but his circadian rhythm was telling him something different. 9 am, to be exact.

Our circadian rhythm is quite a piece of clockwork. It can be recalibrated, but only in very smalls steps.

For every day you are in a different time zone, your suprachiasmatic nucleus can only readjust by about one hour

It would take almost two full weeks to be fully recalibrated to New York’s time!

After spending 40 minutes lying down on the bed with his eyes wide open, Greg decided to call some friends in town.

A few drinks lead to more drinking, and Greg was back to the hotel well after 1 am, conservatively drunk. Alcohol did help to put him to sleep, and he was pretty much knocked out instantly after falling in his bed.

Day 2

After three alarm snoozes, Greg was finally woken up from a dreamless night by Steve’s call. “Hey, I hope I’m not waking you up. How’s the outlook?” After a few seconds of near mouth paralysis due to brain numbness, Greg replied, “Actually … you just woke me up. Thanks for that. Alarm didn’t cut it. Hum … outlook. Right. Yes! Quite positive I’d say. They asked for more detailed projections. I’m on it. I’m pretty confident.”

“Happy to hear that! Let me know if I can help in any way.”

“Before I forget,” Steve continued after a short blank, “have you made up your mind?”

Greg exhaled forcefully. “Sorry Steve, I need more time. I’d rather focus on the task at hand if you don’t mind.”

“All good, all good!” Steve replied in a reassuring voice. “I’m just eager to know. Anyways, keep me posted. And good luck with the presentation. We really need this business.”

Ending the call, Greg stared at the wall in front of him for a few minutes while his brain was rebooting, attempting to retrieve events from the day before. He could recollect many snippets of memory, but they were all disconnected and out of order.

Memory consolidation

One benefit of sleep is memory consolidation. We have a limited amount of conscious memory space that works a little bit like RAM in a computer. While we’re sleeping, our brain processes information stored in our conscious memory and decides if it should be kept there or archived in longer-term memory (or even deleted completely) to free up some space for new information. The bulk of this process seems to be happening during NREM sleep when we are the least active. Then, during REM sleep, we perform many simulations based on the recently processed information, which is a necessary step for memory consolidation.

Alcohol is a sedative, and it is known to be a powerful suppressor of REM sleep, which is why drunk nights are often dreamless nights. That also explains why too much drinking can result in memory loss the following day and why Greg struggled on his bed.

“Numbers! I need to crunch numbers,” he finally recalled, and threw himself on a chair, his computer on his laps before telling himself “coffee first!”

While he didn’t remember all the meeting details, he did remember a few important points he had felt strongly about and started working on them. He also had forgotten about the 9:00 am meeting with the local team and was surprised to see an email asking for his whereabouts. He apologized, and they reconvened the meeting online.

Last bet

Going over the numbers with the team helped boost his confidence. There were still a few hours until his second meeting with the client, and Greg decided to bet on a nap. There was a risk he would feel even more miserable after the nap, but he was convinced that a couple of extra hours of sleep could at least replenish his energy levels.

And he was right. His nap did even better than that; it helped consolidate the information he had just acquired a few hours earlier.

On his way to the client’s office, he felt rather serene. The meeting was a complete success, and the CEO nodded more than once. They thanked him for his responsiveness and told him they would be considering his proposal seriously.

Greg called the local team to congratulate them for their support while checking out from his hotel on his way to the airport.

He had done everything he could and wouldn’t have any regret even if the client were to decline the proposal.

His flight back was uneventful, but this time he did manage to sleep a few hours.

Arriving at Narita airport, he checked his emails while debarking the plane and saw one from Steve with a subject in uppercase letters saying, “THEY SIGNED! NICE WORK!”

He felt immediately relieved and headed back home with a smile on his face. “I can now sleep,” he told himself but then remembered that there was one more thing. “My decision. I need to decide.” This time, he was going to sleep on it.

Moment of truth

After a long-overdue night of sleep, Greg woke up a different man. He felt energized and optimistic as if good things were going to happen today. He also felt that something had changed within him. The anxiety that had been building up over the last few days was pretty much gone. He was ready to make a decision.

Breathing slowly and with confidence, he took his phone and, without hesitation, pressed the call button. “Steve? It’s Greg. I made my mind.”

“Oh, I’m glad to hear that. And what will it be?” Steve asked enthusiastically. Greg took a deep breath and answered, “I’ll take the blue one.”

“Good choice indeed!”

Two days later, Greg was woken up by the delivery man.

Half-awake, he ran down the stairs to get the package he had been dreaming about for the last few days.

And there it was: AKB48 new single special box, “BLUE” edition, with a blue penlight. Steve, who chose the red, and him were now fully equipped to enjoy to the fullest the next concert in Akihabara of their favorite idol unit.

— The end —

Moral of the story

What happened to Greg in this story happens to many people every day. As with many things in life, we don’t think much about sleep and take it for granted. Below are a few takeaways:

  • There are still many things we don’t understand about sleep, and we’re not even sure why and how we came to snooze, but one thing is sure: we need a lot of it.
  • Our unique ability to enjoy extended periods of REM sleep may have contributed to our advanced cognitive development compared to other species. We may not have been where we are today if we had stayed in the trees. (yes, we’d still be in the trees, I know)
  • You are not lazy if you can’t wake up at 6:00 am. It might just be in your genes.
  • You can’t produce melatonin in a bright room. Try to get your bedroom as dark as possible, and keep your phone out of it!
  • Alcohol may help you fall asleep, but it also suppresses REM sleep. Moderation is the name of the game.
  • A quick nap is often more beneficial than several cups of coffee. And coffee doesn’t help you with memory consolidation!
  • Next time you have an important decision to make, sleep on it. Literally.

I hope you have enjoyed this experiment. I wanted to try something new and original, by disseminating informative content through a hopefully intriguing story.

If you’re wondering about Greg, he’s doing great, and he is now more conscious about sleep (although, he still does a few all-nighters with Steve from time to time when they miss their last train after an idol concert in Akihabara).

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