Are you getting enough sleep? What are the long-term effects of sleep deprivation?
According to Johann Hari in his book Stolen Focus, one of the factors contributing to the attention crisis is sleep deprivation. He believes we’re not getting enough sleep and we’re suffering from five dangerous effects.
Continue reading for the five long-term effects of sleep deprivation.
Are You Getting Enough Sleep?
Hari argues that sleep deprivation is not an isolated problem. The average sleep time an adult gets each night is an hour less than it was at the beginning of the 20th century. For children, the lost sleep time amounts to an hour and 25 minutes. (Shortform note: The percentage of adults sleeping significantly less than the recommended seven hours a day is so high that the CDC declared it a public health epidemic.)
Before getting into the long-term effects of sleep deprivation, Hari cites two possible explanations for widespread lack of sleep:
1) Artificial light. Evolution made humans sensitive to light, but artificial lights interfere with our programming. Earlier humans would rise with the sun and go to sleep by sunset, but they also got a second wind around four in the afternoon, just as the sun began to set. That helped them reach safety or finish tasks before sunset. Now, Hari says, we don’t notice that change in natural light because we rely on artificial lighting. We still get that second wind but later in the evening, when we’re supposed to be getting ready for sleep.
2) Consumer capitalism. Sleep deprivation fuels the economy. Our economy relies on people consuming and producing as much as possible, and that can only happen while they’re awake.
(Shortform note: The availability of artificial light and the changing economy also limit your ability to take an afternoon nap to offset a night of insufficient sleep. Studies show that many societies considered segmented sleep normal before industrial times. People had the opportunity to nap during the day and adjust their sleeping schedule to match seasonal sunlight and temperature changes. However, the pressure of the economy and the ability to use technology to adjust the light and temperature inside buildings made siestas less common.)
The Effects of Sleep Deprivation
According to Hari, sleep deprivation diminishes your cognitive ability in five ways:
1) Your brain can’t make new connections. While you sleep, your brain makes connections among the information you learned during the day. These connections are a source of creativity. When you sleep too little, your brain creates fewer connections and becomes less creative.
2) Your brain can’t store information in its long-term memory. While you sleep, your brain retraces everything you learned during the day. The information moves to long-term storage, where you can access it even after it disappears from your short-term memory. When you don’t sleep enough, your brain doesn’t have time to move information into storage.
3) Your brain can’t cleanse itself. While you sleep, the cerebrospinal fluid cleans your brain and gets rid of the waste that accumulates throughout the day. If you’re not getting enough sleep, the brain doesn’t have time to clean up.
4) Your brain can’t dream. Dreams typically occur during the rapid eye movement (REM) stage of sleep and help you process the emotions you felt during the day without triggering stress hormones. But the most intense REM stages usually happen once you’ve been sleeping for seven or eight hours, which many people never get to.
5)Your brain stops paying attention. When you’re tired, you have lapses of less than a second in which you stop registering the information that’s right in front of you. These “attentional blinks” result from part of the brain falling asleep.
Sleep Deprivation’s Effects Are Insidious
Many people are sleep-deprived but don’t notice the negative impact it’s having on their cognitive skills. In Why We Sleep, Matthew Walker explains that sleep deprivation is an insidious problem because when you’re sleep-deprived, you don’t know how poorly you’re performing. And if you’re chronically sleep-deprived, your low performance becomes a new baseline, so you lose perspective. Walker warns that the combination of reduced concentration and an inflated sense of your capabilities in a sleep-deprived state is especially harmful during high-risk activities, like driving.
In addition to impairing cognitive function for the reasons Hari enumerates, chronic sleep deprivation has a host of ill effects on the body—for example, contributing to long-term problems such as high blood pressure, diabetes, heart attack, stroke, depression, and depressed immune function.
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Like what you just read? Read the rest of the world's best book summary and analysis of Johann Hari's "Stolen Focus" at Shortform .
Here's what you'll find in our full Stolen Focus summary :
- The seven factors causing the current attention crisis
- Johann Hari's three-part solution to gaining your attention back
- Why society needs to change, not just individuals