Why We Sleep

Unlocking The Power Of Sleep And Dreams

Wizdom App
4 min readSep 28, 2024
Photo by Kate Stone Matheson on Unsplash

All living creatures need sleep. The question is: why?

In Why We Sleep, neuroscientist and sleep expert Dr Matthew Walker presents groundbreaking discoveries about sleep and how it affects all aspects of our physical, mental and emotional health, including our creativity and longevity.

Why We Sleep: An Introduction

Sleep is absolutely essential to all animals, including humans. Insufficient sleep reduces our learning, memory and cognitive abilities, causes brain impairment and increases the risks of numerous diseases from cancer to diabetes, coronary heart diseases and even death.

On the other hand, sleep boosts our mental, emotional and physical health and capabilities in ways that no amount of drugs or medical interventions can provide.

Unfortunately, most people in modern societies are sleep-deprived, and we don’t even realize it because we’re so used to operating at sub-optimal levels. It’s time we understand and unlock the transformative power of sleep.

Let’s now take a quick look at some of those ideas in this Why We Sleep summary.

What is Sleep?

REM and NREM Sleep

Every night, your brain switches between 2 types of sleep: REM and NREM sleep.

  1. Non-rapid eye movement (NREM) sleep is characterized by deep, slow brainwaves that’re 10x slower than when you’re awake. During deep NREM sleep, we experience a sensory blackout, and our cortex (the logical center of our brain) is relaxed. Your entire brain is now fully aligned to distill and transfer selected memories from your short-term memory (in your frontal lobes) to your long-term memory (at the back of your brain).
  2. Rapid eye movement (REM) sleep is characterized by faster brainwave activity that’s similar to when you’re awake. You brain’s visual, motor, memory and emotional centers are activated, and pockets of feelings, info, memories, motivations etc. are combined into a giant movie screen, i.e. your dreams. Your eyes may move rapidly as you dream.

When we’re awake, we constantly receive new sensory inputs from the external environment. NREM sleep reinforces and stores those raw data and skills.

REM sleep integrates these ingredients by connecting them with one another and with our past experiences and knowledge, to improve our mental model of how the world works, develop new insights and solve problems innovatively.

Basically, NREM and REM serve different but equally-vital functions. When you don’t get full 8 hours of sleep, you lose out on chunks of NREM or REM sleep with serious repercussions.

Why We Sleep & Why You Should Sleep

Sleep is the ultimate therapy and enhancer to provide a range of benefits that medicine and other interventions cannot In a nutshell:

Sleep benefits the brain with 3 main cognitive benefits:

(i) improved memory

(ii) improved motor task proficiency or “muscle memory”

(iii) improved creativity. REM sleep connects your different memories, experiences and skills to create new ideas and insights.

Dreams deliver real benefits. REM-sleep and dreams

(i) reduce the pain from traumatic events

(ii) helps us decode facial expressions accurately

(iii) improve problem-solving and creativity.

Sleep-deprivation harms the brain to

(i) impair memory

(ii) worsen focus/concentration

(iii) worsen emotional control, and

(iv) play a role in mental illnesses from psychiatric conditions to Alzheimer’s Disease.

Sleep-deprivation harms the body

— it damages every aspect of our physiology and is linked to a shorter lifespan and a host of diseases like cancer and heart diseases. That’s because it severely impacts your cardiovascular system, metabolism, reproductive system, immunity system, cancer growth and inflammation, and even genetic activity and makeup.

  • Sleep disorders can disrupt our lifestyle and well-being. Such disorders include somnambulism, insomnia and narcolepsy. At the extreme, sleep deprivation can even cause death.

Meanwhile, here are 3 simple tips that you can apply straight away to start improving your sleep quality and quantity:

  • Use blackout curtains to keep your bedroom completely dark
  • Take a hot bath (or warm your hands/feet) before bed, to draw heat to the skin surface and reduce your core body temperature
  • Do not consume alcohol close to bedtime: it’s actually a sedative that disrupts REM sleep and causes you to wake up throughout the night.

“Sleep is the single most effective thing we can do to reset our brain and body health each day — Mother Nature’s best effort yet at contra-death.”

--

--

Wizdom App
Wizdom App

Written by Wizdom App

Read or listen to bite-sized book summaries and podcasts in the first-of-its-kind Audio Immersive Experience with Wizdom! https://onelink.to/5hekcb