Night School

Night School

Wake Up to the Power of Sleep

Richard Wiseman

Summary in 100 words or less

Your brain removes unwanted toxins during sleep. Poor sleep slams cognitive performance. Sleep in ninety-minute blocks, e.g. 360 minutes (6 hours), 450 minutes (7.5 hours), etc. To improve sleep, avoid bright light before your sleep, keep your room dark and cold, and have a wind-down routine. Napping is good—make it a part of your daily routine. Your dreams help identify your worries and concerns, at the same time, see new and innovative solutions to your problems.


My Highlights

Increased workloads, twenty-four-hour media, and permanent Internet access have combined to create a world that now never sleeps.

Poor sleeping habits also reduce productivity, prevent learning, disrupt relationships, cramp creative thinkings, and sap self-control.

The ninety-minute rule. You will feel most refreshed when you awake at the end of a ninety-minute sleep cycle because you will be closest to your normal waking state. To maximize the chances of this happening, figure out when you want to wake up, then count back in ninety-minute blocks to find a time near to when you want to go to sleep.

At certain times of the day, the suprachiasmatic nucleus causes the pineal gland to produce a sleep-inducing hormone called ‘melatonin’, making you feel drowsy and tired. Your internal clock sends these signals as part of a highly predictable pattern that repeats itself every twenty-four hours. Sleep scientists refer to this pattern as a ‘circadian rhythm’, a term derived from the Latin word circa, meaning ‘around’, and dies, meaning ‘a day’.

Top tips to help overcome jet lag:

  • Make good use of the days before you fly by starting to shift your body clock to the time at your destination
  • Book flights that will minimize jet lag by following the simple adage, ‘Fly east, fly early. Fly west, fly late’
  • As soon as you board the plane, adjust your watch to show the time at your destination, and try to fit into this new time schedule as soon as possible

Even a small amount of sleep deprivation can dramatically increase the chances of you having a serious accident in everyday life.

Spend just a few nights sleeping for seven hours or less and your brain goes into slow motion. To make matters worse, you will continue to feel fine and so don’t make allowance for your sluggish mind. Within just a couple of days, this level of sleep deprivation transforms you into an accident waiting to happen.

Your brain makes up just 2 percent of your weight but uses 20 percent of all the energy your body produces. When you are sleep deprived, your body struggles to extract glucose from the bloodstream, and so your brain cannot think straight.

The front part of your brain plays a key role in determining your level of willpower. When you are sleep deprived, the low energy levels in this part of the brain can be especially damaging because it disrupts your sense of self-control and discipline.

Your brain cells continually produce a kind of ‘toxic waste’ that, if allowed to build up, disrupts your thoughts, behavior, and mood. To avoid this happening, your body regularly flushes a special cleaning liquid called ‘cerebrospinal fluid’ (CSF) through your brain tissue. CSF removes the unwanted waste and carries it down to your liver for detoxification. Neuroscientists from the University of Rochester Medical Center recently made a remarkable discovery about the role of this vital waste disposal process.

When you fall asleep, your brain becomes far more efficient at removing the unwanted toxins that build up during the day. On the flip side, if you fail to get enough sleep, these toxins remain in your brain, causing you to feel foggy-headed and irritable.

Here is a guide to creating the perfect space for sleeping:

  • Embrace the darkness
  • The sound of silence
  • Ensure that your room is not too hot or too cold
  • Think about how secure you feel when you sleep
  • Many sleep scientists recommend that you only sleep and have sex in your bedroom

Super-sleepers said often that many of their daytime activities were designed to help them nod off at night

  • Don’t over-nap
  • Get physical
  • Busy the mind
  • Know when to head to bed

Although any type of light stops you feeling sleepy, research has shown that light towards the blue end of the spectrum is especially effective at keeping you awake. Unfortunately, computer screens, tablets, smartphones, flat-screen television, and LED lighting all emit large amounts of blue light.

Lying in a warm bath artificially raises your body temperature, but when you climb out of the bath this temperature abruptly drops and sends a signal to your body that you are ready to sleep.

Although research shows that even a small amount of alcohol does indeed put you to sleep quicker, it also gives you a more disturbed night, increases the chances of snoring, and disrupts dreaming.

One of the simplest and most effective ways of improving children’s sleep involves creating a bedtime routine.

It’s important to avoid sleeping on your back, as your tongue and soft tissue in the throat are likely to fall backward and obstruct your airway.

Repeatedly playing phrases throughout the night doesn’t boost people’s memories, sleep is essential for strong away information that you have encountered during the day. The take-home message is clear: do not skimp on sleep.

When you are preparing for an important exam or interview, you might be tempted to stay up late the night before trying to cram information into your head. Avoid the temptation. It’s a terrible idea and you will be much better off getting an early night. Not only will you be more refreshed when you wake up, but you will also be better able to remember what you learned the day before.

Napping is often seen as a form of laziness. Nothing could be further from the truth. Hundreds of experiments have demonstrated the enormous benefits associated with even the shortest of sleeps, and so it is vital that you make napping part of your daily routine.

Putting your head down for just a few minutes each day will help you develop a better memory, be more alert, increase your reaction time, and boost your productivity. Perhaps most important at all, it may even save your life.

According to the ‘continuity hypothesis’ theory, most dreams are a continuation of what is happening in your everyday life. If, for instance, you spend most of your day in the office, then you will tend to have lots of desk-based dreams.

Regardless of what’s happening in your waking life, around 80 percent of your dreams involve some type of negative emotion. This level of negativity goes through the roof if you become stressed in your waking life.

After much head-scratching, several sleep scientists speculated that these negative scenarios weren’t designed to terrify you, but rather to help you cope with your everyday concerns and worries.

Your dreams don’t just help you identify your worries and concerns, but can also help you see new and innovative solutions to your problems.

In an experiment, volunteers who had been exposed to the more pleasant smell had much more positive dreams. So if you want to have sweet dreams, ensure that your bedroom contains just a hint of your favorite smell.

More book notes

The Power of Habit
The World's Fittest Book
The Winner’s Brain
The 7 Habits of Highly Effective People
High Performance Habits

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