Book Notes Flashcards
“One way in which Mother Nature has perhaps helped adolescents unbuckle themselves from their parents is to march their circadian rhythms forward in time, past that of their adult mothers and fathers”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
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“The changes in deep NREM sleep always precede the cognitive and developmental milestones within the brain by several weeks or months, implying a direction of influence: deep sleep may be a driving force of brain maturation, not the other way around.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“There are two main culprits of drowsy-driving accidents. The first is people completely falling asleep at the wheel. This happens infrequently, however, and usually requires an individual to be acutely sleep-deprived (having gone without shut-eye for twenty-plus hours). The second, more common cause is a momentary lapse in concentration, called a microsleep. These last for just a few seconds, during which time the eyelid will either partially or fully close. They are usually suffered by individuals who are chronically sleep restricted, defined as getting less than seven hours of sleep a night on a routine basis.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“YOU DO NOT KNOW HOW SLEEP-DEPRIVED YOU ARE WHEN YOU ARE SLEEP-DEPRIVED
The third key finding, common to both of these studies, is the one I personally think is the most harmful of all. When participants were asked about their subjective sense of how impaired they were, they consistently underestimated their degree of performance disability.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“YOU DO NOT KNOW HOW SLEEP-DEPRIVED YOU ARE WHEN YOU ARE SLEEP-DEPRIVED
The third key finding, common to both of these studies, is the one I personally think is the most harmful of all. When participants were asked about their subjective sense of how impaired they were, they consistently underestimated their degree of performance disability.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“After thirty years of intensive research, we can now answer many of the questions posed earlier. The recycle rate of a human being is around sixteen hours. After sixteen hours of being awake, the brain begins to fail. Humans need more than seven hours of sleep each night to maintain cognitive performance. After ten days of just seven hours of sleep, the brain is as dysfunctional as it would be after going without sleep for twenty-four hours. Three full nights of recovery sleep (i.e., more nights than a weekend) are insufficient to restore performance back to normal levels after a week of short sleeping. Finally, the human mind cannot accurately sense how sleep-deprived it is when sleep-deprived.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“They believed that by inserting a nap at the front end of an incoming bout of sleep deprivation, you could insert a buffer, albeit temporary and partial, that would protect the brain from suffering catastrophic lapses in concentration. They were right. ”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“No matter what you may have heard or read in the popular media, there is no scientific evidence we have suggesting that a drug, a device, or any amount of psychological willpower can replace sleep. Power naps may momentarily increase basic concentration under conditions of sleep deprivation, as can caffeine up to a certain dose.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“Insufficient sleep does not, therefore, push the brain into a negative mood state and hold it there. Rather, the under-slept brain swings excessively to both extremes of emotional valence, positive and negative.
”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“There is no major psychiatric condition in which sleep is normal. This is true of depression, anxiety, post-traumatic stress disorder (PTSD), schizophrenia, and bipolar disorder (once known as manic depression)…Indeed, many of the brain regions commonly impacted by psychiatric mood disorders are the same regions that are involved in sleep regulation and impacted by sleep loss. Further, many of the genes that show abnormalities in psychiatric illnesses are the same genes that help control sleep and our circadian rhythms.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“the hippocampus—the information “in-box” of the brain that acquires new facts. There was lots of healthy, learning-related activity in the hippocampus in the participants who had slept the night before. However, when we looked at this same brain structure in the sleep-deprived participants, we could not find any significant learning activity whatsoever. It was as though sleep deprivation had shut down their memory in-box, and any new incoming information was simply being bounced”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“In other words, 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. ”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“When we wake each morning, our brains can once again function efficiently thanks to this deep cleansing.
So what does this have to do with Alzheimer’s disease? One piece of toxic debris evacuated by the glymphatic system during sleep is amyloid protein—the poisonous element associated with Alzheimer’s disease…wakefulness is low-level brain damage, while sleep is neurological sanitation.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“I have always found it curious that Margaret Thatcher and Ronald Reagan—two heads of state that were very vocal, if not proud, about sleeping only four to five hours a night—both went on to develop the ruthless disease.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“I should note that in many of these studies, the relationship between short sleep and heart failure remains strong even after controlling for other known cardiac risk factors, such as smoking, physical activity, and body mass. A lack of sleep more than accomplishes its own, independent attack on the heart.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“every experiment that has investigated the impact of deficient sleep on the human body has observed an overactive sympathetic nervous system. For as long as the state of insufficient sleep lasts, and for some time thereafter, the body remains stuck in some degree of a fight-or-flight state”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“That’s precisely what researchers did to a group of overweight men and women who stayed in a medical center for an entire fortnight. However, one group of individuals were given just five and a half hours’ time in bed, while the other group were offered eight and a half hours’ time in bed.
Although weight loss occurred under both conditions, the type of weight loss came from very different sources. When given just five and a half hours of sleep oppurtunity, more than 70 percent of the pounds lost came from lean body mass—muscle, not fat. Switch to the group offered eight and a half hours’ time in bed each night and a far more desirable outcome was observed, with well over 50 percent of weight loss coming from fat while preserving muscle”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“However, that flu shot is only effective if your body actually reacts to it by generating antibodies…Those participants who obtained seven to nine hours’ sleep in the week before getting the flu shot generated a powerful antibody reaction, reflecting a robust, healthy immune system…Perhaps the sleep-deprived individuals could still go on to produce a more robust immune reaction if only they were given enough recovery sleep time? It’s a nice idea, but a false one”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“Cancers are known to use the inflammation response to their advantage. For example, some cancer cells will lure inflammatory factors into the tumor mass to help initiate the growth of blood vessels that feed it with more nutrients and oxygen. Tumors can also use inflammatory factors to help further damage and mutate the DNA of their cancer cells, increasing the tumor’s potency. Inflammatory factors associated with sleep deprivation may also be used to help physically shear some of the tumor from its local moorings, allowing the cancer to up-anchor and spread to other territories of the body.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“REM sleep can therefore be considered as a state characterized by strong activation in visual, motor, emotional, and autobiographical memory regions of the brain, yet a relative deactivation in regions that control rational thought”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“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…The theory proposed that a contributing mechanism underlying the PTSD is the excessively high levels of noradrenaline within the brain that blocks the ability of these patients from entering and maintaining normal REM-sleep dreaming…the repetitive nightmares reported in PTSD patients—a symptom so reliable that it forms part of the list of features required for a diagnosis of the condition. If the brain cannot divorce the emotion from memory across the first night following a trauma experience, the theory suggests that a repeat attempt of emotional memory stripping will occur on the second night…Prazosin was gradually lowering the harmful high tide of noradrenaline within the brain, giving these patients healthier REM-sleep quality…prazosin has become the officially approved drug by the VA for the treatment of repetitive trauma nightmares, and has since received approval by the US Food and Drug Administration for the same benefit.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“It postulated that the process of REM-sleep dreaming accomplishes two critical goals: (1) sleeping to remember the details of those valuable, salient experiences, integrating them with existing knowledge and putting them into autobiographical perspective, yet (2) sleeping to forget, or dissolve, the visceral, painful emotional charge that had previously been wrapped around those memories.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“Upon awakenings from NREM sleep, participants did not appear to be especially creative, solving few of the anagram puzzles. But it was a different story when I woke them up out of REM sleep, from the dreaming phase. Overall, problem-solving abilities rocketed up, with participants solving 15 to 35 percent more puzzles when emerging from REM sleep compared with awakenings from NREM sleep or during daytime waking performance!”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“As with the effects of REM sleep on our emotional and mental well-being explored in the previous chapter, the latter would prove that REM sleep is necessary but not sufficient. It is both the act of dreaming and the associated content of those dreams that determine creative success…The content of one’s dreams, more than simply dreaming per se, or even sleeping, determines problem-solving success.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“How can I understand and connect that which I have recently learned with that I already know, and in doing so, discover insightful new links and revelations?” Moreover, “What have I done in the past that might be useful in potentially solving this newly experienced problem in the future?” Different from solidifying memories, which we now realize to be the job of NREM sleep, REM sleep, and the act of dreaming, takes that which we have learned in one experience setting and seeks to apply it to others stored in memory.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“The content of one’s dreams, more than simply dreaming per se, or even sleeping, determines problem-solving success”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“grasping the ball bearings. Only then would Edison ease back and allow sleep to consume him whole. At the moment he began to dream, his muscle tone would relax and he would release the ball bearings, which would crash on the metal saucepan below, waking him up. He would then write down all of the creative ideas that were flooding his dreaming mind.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“sleepwalking, sleep talking, sleep eating, sleep texting, sleep sex, and, very rarely, sleep homicide…Understandably, most people believe these events happen during REM sleep as an individual is dreaming, and specifically acting out ongoing dreams. However, all these events arise from the deepest stage of non-dreaming (NREM) sleep, and not dream (REM) sleep…Trapped between the two worlds of deep sleep and wakefulness, the individual is confined to a state of mixed consciousness—neither awake nor asleep. In this confused condition, the brain performs basic but well-rehearsed actions, such as walking over to a closet and opening it, placing a glass of water to the lips, or uttering a few words or sentences…There are the clear and unmistakable slow electrical waves of deep NREM sleep, with no sign of fast, frenetic waking brainwave activity.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“After falling asleep on the couch around 1:30 a.m. while watching television, Parks arose and got in his car, barefoot. Depending on the route, it is estimated that Parks drove approximately fourteen miles to his in-laws’ home. Upon entering the house, Parks made his way upstairs, stabbed his mother-in-law to death with a knife he had taken from their kitchen”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“ insomnia, researchers have focused on examining the biological causes that underlie emotional turmoil. One common culprit has become clear: an overactive sympathetic nervous system, which, as we have discussed in previous chapters, is the body’s aggravating fight-or-flight mechanism”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“Researchers have placed healthy sleepers and insomnia patients in a brain scanner and measured the changing patterns of activity as both groups try to fall asleep. In the good sleepers, the parts of the brain related to inciting emotions (the amygdala) and those linked to memory retrospection (the hippocampus) quickly ramped down in their levels of activity as they transitioned toward sleep, as did basic alertness regions in the brain stem. This was not the case for the insomnia patients. Their emotion-generating regions and memory-recollection centers all remained active. This was similarly true of the basic vigilance centers in the brain stem that stubbornly continued their wakeful watch. All the while the thalamus—the sensory gate of the brain that needs to close shut to allow sleep—remained active and open for business in insomnia patients.
Simply put, the insomnia patients could not disengage from a pattern of altering, worrisome, ruminative brain activity”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“Cataplectic attacks are not random, but are triggered by moderate or strong emotions, positive or negative. Tell a funny joke to a narcoleptic patient, and they may literally collapse in front of you…A narcoleptic patient is banished to a monotonic existence of emotional neutrality…Instead, what the strong emotion has triggered is the total (or sometimes partial) body paralysis of REM sleep without the sleep of the REM state itself. Cataplexy is therefore an abnormal functioning of the REM-sleep circuitry within the brain,”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“When orexin is released down onto your brain stem, the switch has been unambiguously flipped, powering up the wakefulness-generating centers of the brain stem. Once activated by the switch, the brain stem pushes open the sensory gate of the thalamus, allowing the perceptual world to flood into your brain, transitioning you to full, stable wakefulness.
At night, the opposite happens. The sleep-wake switch stops releasing orexin onto the brain stem”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“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…First, alcohol fragments sleep, littering the night with brief awakenings. Alcohol-infused sleep is therefore not continuous and, as a result, not restorative. Unfortunately, most of these nighttime awakenings go unnoticed by the sleeper since they don’t remember them”
“Second, alcohol is one of the most powerful suppressors of REM sleep that we know of…The pent-up REM-sleep pressure erupts forcefully into waking consciousness, causing hallucinations, delusions, and gross disorientation. The technical term for this terrifying psychotic state is “delirium tremens.”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
“your core temperature needs to decrease by 2 to 3 degrees Fahrenheit, or about 1 degree Celsius. For this reason, you will always find it easier to fall asleep in a room that is too cold than too hot”
Excerpt From
Why We Sleep
Matthew Walker
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=0
This material may be protected by copyright.
