By Ruba Qaqish
In his book Why We Sleep: Unlocking the Power of Sleep and Dreams (2017), University of California Berkeley professor Matthew Walker argues that sleep is the third pillar of health alongside exercise and a healthy diet. It could even be that the other two pillars actually depend on the foundation of a good night’s sleep.
Walker describes how even minimal sleep loss can have devastating effects on physical and mental health. He expresses concern that two-thirds of adults in developed nations fall short of achieving the needed seven to nine hours of sleep each night. No wonder the World Health Organization describes sleep loss as an epidemic.
HOW DO WE KNOW IF WE ARE SLEEP DEPRIVED?
• If you didn’t set an alarm clock, would you oversleep?
• Do you find yourself re-reading things?
• Do you need caffeine to function optimally before noon?
If you answered yes to any of these questions, then you are likely sleep deprived. Two factors determine when we feel sleepy – our individual circadian rhythm (regulated by the hormone melatonin) and sleep pressure (caused by the build-up of the chemical adenosine in the brain throughout the day). Caffeine works by blocking the receptors that adenosine affects. The release of melatonin is affected by the time and type of light we are exposed to.
HOW DO WE SLEEP?
Our sleep consists of cycles, each containing a period of non-rapid eye movement (NREM) sleep and a period of REM sleep.
Our time awake is the reception phase when we experience and constantly learn about the world around us. NREM sleep is the reflection phase when we store and strengthen the raw ingredients of new facts and skills. REM sleep is the integration phase when we interconnect these raw ingredients with each other and with our past experiences, and in doing so, build a more accurate model of how the world works. That building phase includes developing innovative insights and problem-solving abilities. REM sleep also recalibrates and fine-tunes the emotional circuits of our brain.
WHY SHOULD WE SLEEP?
Sleep is the most effective thing we can do to reset our brain and body health each day.
Of the many advantages of sleep for the brain, the benefit for memory is especially impressive, both before learning, to prepare your brain for making new memories, and after learning, to cement those memories and prevent forgetting. In other words, if we don’t sleep the first night after learning something, we lose the chance to consolidate those memories.
Sleep is also responsible for motor-skill enhancement. Increases in motor speed and accuracy are directly related to NREM sleep, especially during the last two hours of an eight-hour night of sleep.
Walker explains that sleep is responsible for our ability to concentrate. In addition to slower reaction times, when tired we can lapse into “microsleeps,” when we become totally unresponsive for a second or two, which is long enough to cause serious damage while driving or operating a machine.
A final benefit of sleep is the most remarkable of all: creativity. Dreams during REM sleep allow us to make unusual and creative connections among different topics.
Many great intellectuals report that their best ideas just “came to them” upon waking.
CAN WE CATCH UP ON LOST SLEEP?
Unfortunately, no. No species can ever “sleep back” what they have lost, which leads to some really saddening consequences. Walker argues that a lack of sleep correlates with numerous diseases,
including Alzheimer’s disease, cancer, cardiovascular disease, immune system diseases, many mental illnesses, infertility, and obesity.
Our professional success depends on our creativity, concentration, and problem-solving abilities, and on our emotional toughness. Is a good night’s sleep on your list of priorities? According to Walker, it should be at the top.
First published in the March 2020 edition of The Business Advisor.