Why We Sleep Quotes

“It is the lack of REM sleep—that critical stage occurring in the final hours of sleep that we strip from our children and teenagers by way of early school start times—that creates the difference between a stable and unstable mental state.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“Unnecessarily bankrupting the sleep of a teenager could make all the difference in the precarious tipping point between psychological wellness and lifelong psychiatric illness.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“More than 80 percent of public high schools in the United States begin before 8:15 a.m. Almost 50 percent of those start before 7:20 a.m. School buses for a 7:20 a.m. start time usually begin picking up kids at around 5:45 a.m. As a result, some children and teenagers must wake up at 5:30 a.m., 5:15 a.m., or even earlier, and do so five days out of every seven, for years on end. This is lunacy. Could you concentrate and learn much of anything when you had woken up so early? Keep in mind that 5:15 a.m. to a teenager is not the same as 5:15 a.m. to an adult. Previously, we noted that the circadian rhythm of teenagers shifts forward dramatically by one to three hours. So really the question I should ask you, if you are an adult, is this: Could you concentrate and learn anything after having forcefully been woken up at 3:15 a.m., day after day after day? Would you be in a cheerful mood? Would you find it easy to get along with your coworkers and conduct yourself with grace, tolerance, respect, and a pleasant demeanor? Of course not. Why, then, do we ask this of the millions of teenagers and children in industrialized nations?”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“Association does not prove causation.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“Add the above health consequences up, and a proven link becomes easier to accept: relative to the recommended seven to nine hours, the shorter your sleep, the shorter your life span. The old maxim “I’ll sleep when I’m dead” is therefore unfortunate. Adopt this mind-set, and it is possible that you will be dead sooner and the quality of that (shorter) life will be worse.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“ask the doctor: “How much sleep have you had in the past twenty-four hours?” The doctor’s response will determine, to a statistically provable degree, whether the treatment you receive will result in a serious medical error, or even death.”
― Matthew Walker, Why We Sleep: The New Science of Sleep and Dreams

“After only a few weeks of treatment, his patients would return to the clinic and, with puzzled amazement, say things like, “Doc, it’s the strangest thing, my dreams don’t have those flashback nightmares anymore. I feel better, less scared to fall asleep at night.” It turns out that the drug prazosin, which Raskind was prescribing simply to lower blood pressure, also has the fortuitous side effect of suppressing noradrenaline in the brain.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“chronotype, is strongly determined by genetics.”
― Matthew Walker, Why We Sleep: The New Science of Sleep and Dreams

“Edison was a habitual daytime napper. He understood the creative brilliance of dreaming, and used”
― Matthew Walker, Why We Sleep: The New Science of Sleep and Dreams

“The current US president, Donald Trump—also a vociferous proclaimer of sleeping just a few hours each night—may want to take note.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“the placebo effect is, after all, the most reliable effect in all of pharmacology.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“...based on epidemiological data, any adult sleeping an average of 6.75 hours a night would be predicted to live only into their early sixties...”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“When communicating science to the general public in lectures or writing, I’m always wary of bombarding an audience with never-ending mortality and morbidity statistics, lest they themselves lose the will to live in front of me. It is hard not to do so with such compelling masses of studies in the field of sleep deprivation. Often, however, a single astonishing result is all that people need to apprehend the point. For cardiovascular health, I believe that finding comes from a “global experiment” in which 1.5 billion people are forced to reduce their sleep by one hour or less for a single night each year. It is very likely that you have been part of this experiment, otherwise known as daylight savings time. In the Northern Hemisphere, the switch to daylight savings time in March results in most people losing an hour of sleep opportunity. Should you tabulate millions of daily hospital records, as researchers have done, you discover that this seemingly trivial sleep reduction comes with a frightening spike in heart attacks the following day. Impressively, it works both ways. In the autumn within the Northern Hemisphere, when the clocks move forward and we gain an hour of sleep opportunity time, rates of heart attacks plummet the day after. A similar rise-and-fall relationship can be seen with the number of traffic accidents, proving that the brain, by way of attention lapses and microsleeps, is just as sensitive as the heart to very small perturbations of sleep. Most people think nothing of losing an hour of sleep for a single night, believing it to be trivial and inconsequential. It is anything but.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“Those children who are fortunate to have the sleep disorder recognized, and who have their tonsils removed, more often than not prove that they do not have ADHD. In the weeks after the operation, a child’s sleep recovers, and with it, normative psychological and mental functioning in the months ahead. Based on recent surveys and clinical evaluations, we estimate that more than 50 percent of all children with an ADHD diagnosis actually have a sleep disorder, yet a small fraction know of their sleep condition and its ramifications.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“No past or current sleeping medications on the legal (or illegal) market induce natural sleep. Don’t get me wrong—no one would claim that you are awake after taking prescription sleeping pills. But to suggest that you are experiencing natural sleep would not be a true assertion. The older sleep medications—termed “sedative hypnotics,” such as diazepam—were blunt instruments. They sedated you rather than assisting you into natural sleep. Understandably, many people mistake the former for the latter. Most of the newer sleeping pills on the market present a similar situation, though they are slightly less heavy in their sedating effects. Sleeping pills, old and new, target the same system in the brain that alcohol does—the receptors that stop your brain cells from firing—and are thus part of the same general class of drugs: sedatives. Sleeping pills effectively knock out the higher regions of your brain’s cortex.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“Consequently, you fall asleep more quickly because your core is colder. Hot baths prior to bed can also induce 10 to 15 percent more deep NREM sleep in healthy adults.IV”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“A bedroom temperature of around 65 degrees Fahrenheit (18.3°C) is a reasonable goal for the sleep of most people, assuming standard bedding and clothing. This surprises many, as it sounds just a little too cold for comfort. Of course, that specific temperature will vary depending on the individual in question and their unique physiology, gender, and age. But like calorie recommendations, it’s a good target for the average human being. Most of us set ambient house and/or bedroom temperatures higher than are optimal for good sleep and this likely contributes to lower quantity and/or quality of sleep than you are otherwise capable of getting.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“Should you have children, you’ve probably seen the same phenomenon when you check in on them late at night: arms and legs dangling out of the bed in amusing (and endearing) ways, so different from the neatly positioned limbs you placed beneath the sheets upon first tucking them into bed. The limb rebellion aids in keeping the body core cool, allowing it to fall and stay asleep.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“Alcohol sedates you out of wakefulness, but it does not induce natural sleep. The electrical brainwave state you enter via alcohol is not that of natural sleep; rather, it is akin to a light form of anesthesia.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“Compared to reading a printed book, reading on an iPad suppressed melatonin release by over 50 percent at night. Indeed, iPad reading delayed the rise of melatonin by up to three hours, relative to the natural rise in these same individuals when reading a printed book.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“The light receptors in the eye that communicate “daytime” to the suprachiasmatic nucleus are most sensitive to short-wavelength light within the blue spectrum—the exact sweet spot where blue LEDs are most powerful. As a consequence, evening blue LED light has a more harmful impact on human nighttime melatonin suppression than the warm, yellow light from old incandescent bulbs, even when their lux intensities are matched.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“El sueño modifica constantemente la arquitectura de la información del cerebro durante la noche. Incluso durante el día, siestas de tan solo veinte minutos pueden ofrecer una ventaja de consolidación de la memoria, siempre que contengan suficiente sueño no-REM.”
― Matthew Walker, Por qué dormimos: La nueva ciencia del sueño

“At the heart of the theory was an astonishing change in the chemical cocktail of your brain that takes place during REM sleep. Concentrations of a key stress-related chemical called noradrenaline are completely shut off within your brain when you enter this dreaming sleep state. In fact, REM sleep is the only time during the twenty-four-hour period when your brain is completely devoid of this anxiety-triggering molecule. Noradrenaline, also known as norepinephrine, is the brain equivalent to a body chemical you already know and have felt the effects of: adrenaline (epinephrine).”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“if you don’t sleep the very first night after learning, you lose the chance to consolidate those memories, even if you get lots of “catch-up” sleep thereafter. In terms of memory, then, sleep is not like the bank. You cannot accumulate a debt and hope to pay it off at a later point in time. Sleep for memory consolidation is an all-or-nothing event. It is a concerning result in our 24/7, hurry-up, don’t-wait society. I feel another op-ed coming on…”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“Power naps may momentarily increase basic concentration under conditions of sleep deprivation, as can caffeine up to a certain dose. But in the subsequent studies that Dinges and many other researchers (myself included) have performed, neither naps nor caffeine can salvage more complex functions of the brain, including learning, memory, emotional stability, complex reasoning, or decision-making.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“In other words, your brain will continue to improve skill memories in the absence of any further practice. It is really quite magical. Yet, that delayed, “offline” learning occurs exclusively across a period of sleep, and not across equivalent time periods spent awake, regardless of whether the time awake or time asleep comes first. Practice does not make perfect. It is practice, followed by a night of sleep, that leads to perfection.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“Which sleep period would confer a greater memory savings benefit—that filled with deep NREM, or that packed with abundant REM sleep? For fact-based, textbook-like memory, the result was clear. It was early-night sleep, rich in deep NREM, that won out in terms of providing superior memory retention savings relative to late-night, REM-rich sleep.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“II In that moment, we had just become privy to an electrical transaction occurring in the quiet secrecy of sleep: one that was shifting fact-based memories from the temporary storage depot (the hippocampus) to a long-term secure vault (the cortex). In doing so, sleep had delightfully cleared out the hippocampus, replenishing this short-term information repository with plentiful free space. Participants awoke with a refreshed capacity to absorb new information within the hippocampus, having relocated yesterday’s imprinted experiences to a more permanent safe hold.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“The second benefit of sleep for memory comes after learning, one that effectively clicks the “save” button on those newly created files. In doing so, sleep protects newly acquired information, affording immunity against forgetting: an operation called consolidation.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams

“The second evolutionary contribution that the REM-sleep dreaming state fuels is creativity. NREM sleep helps transfer and make safe newly learned information into long-term storage sites of the brain. But it is REM sleep that takes these freshly minted memories and begins colliding them with the entire back catalog of your life’s autobiography. These mnemonic collisions during REM sleep spark new creative insights as novel links are forged between unrelated pieces of information. Sleep cycle by sleep cycle, REM sleep helps construct vast associative networks of information within the brain. REM sleep can even take a step back, so to speak, and divine overarching insights and gist: something akin to general knowledge—that is, what a collection of information means as a whole, not just an inert back catalogue of facts.”
― Matthew Walker, Why We Sleep: Unlocking the Power of Sleep and Dreams