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January 28 - February 15, 2020
Seniors therefore complain about and seek treatment for their health issues when visiting their GP, but rarely ask for help with their equally problematic sleep issues.
first explore the effective and scientifically proven non-pharmacological interventions that a doctor who is board certified in sleep medicine can provide.
As healthy teenagers, we enjoyed a sleep efficiency of about 95 percent.
Poor memory and poor sleep in old age are therefore not coincidental, but rather significantly interrelated.
poor sleep is one of the most underappreciated factors contributing to cognitive and medical ill health in the elderly, including issues of diabetes, depression, chronic pain, stroke, cardiovascular disease, and Alzheimer’s disease.
we obtain most of our deep NREM sleep early in the night, and much of our REM sleep (and lighter NREM sleep) late in the night.
“I have an experience that seems far too frequent to be chance. I will be practicing a particular piece, even late into the evening, and I cannot seem to master it. Often, I make the same mistake at the same place in a particular movement. I go to bed frustrated. But when I wake up the next morning and sit back down at the piano, I can just play, perfectly.”
your brain will continue to improve skill memories in the absence of any further practice.
Obtain anything less than eight hours of sleep a night, and especially less than six hours a night, and the following happens: time to physical exhaustion drops by 10 to 30 percent, and aerobic output is significantly reduced.
Similar impairments are observed in limb extension force and vertical jump height, together with decreases in peak and sustained muscle strength. Add to this marked impairments in cardiovascular, metabolic, and respiratory capabilities that hamper an underslept body, including faster rates of lactic acid buildup, reductions in blood oxygen saturation, and converse increases in blood carbon dioxide, due in part to a reduction in the amount of air that the lungs can expire. Even the ability of the body to cool itself during physical exertion through sweating—a critical part of peak
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Post-performance sleep accelerates physical recovery from common inflammation, stimulates muscle repair, and helps restock cellular energy in the form of glucose and glycogen.
the most dramatic time of skilled motor learning in any human’s life occurs in the first years after birth, as we start to stand and walk. It is of little surprise that we see a spike in stage 2 NREM sleep, including sleep spindles, right around the infant’s time of transition from crawling to walking.
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.
How much sleep can a human lose each night, and over how many nights, before critical processes of the brain fail?
Ten days of six hours of sleep a night was all it took to become as impaired in performance as going without sleep for twenty-four hours straight.
Sixty years of scientific research prevent me from accepting anyone who tells me that he or she can “get by on just four or five hours of sleep a night just fine.”
After being awake for nineteen hours, people who were sleep-deprived were as cognitively impaired as those who were legally drunk.
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.
drunk drivers are often late in braking, and late in making evasive maneuvers. But when you fall asleep, or have a microsleep, you stop reacting altogether.
We have, however, discovered a very rare collection of individuals who appear to be able to survive on six hours of sleep, and show minimal impairment—a sleepless elite, as it were.
“The number of people who can survive on five hours of sleep or less without any impairment, expressed as a percent of the population, and rounded to a whole number, is zero.”
There is but a fraction of 1 percent of the population who are truly resilient to the effects of chronic sleep restriction at all levels of brain function.
the amygdala—a key hot spot for triggering strong emotions such as anger and rage, and linked to the fight-or-flight response—showed well over a 60 percent amplification in emotional reactivity in the participants who were sleep-deprived.
the under-slept brain swings excessively to both extremes of emotional valence, positive and negative.
Studies of adolescents have identified a link between sleep disruption and suicidal thoughts, suicide attempts, and, tragically, suicide completion in the days after.
suicide is the second-leading cause of death in young adults in developed nations after car accidents.
insufficient sleep during childhood significantly predicts early onset of drug and alcohol use in that same child during their later adolescent years, even when controlling for other high-risk traits, such as anxiety, attention deficits, and parental history of drug use.
There is no major psychiatric condition in which sleep is normal.
I am suggesting that sleep disruption remains a neglected factor contributing to the instigation and/or maintenance of numerous psychiatric illnesses, and has powerful diagnostic and therapeutic potential that we are yet to fully understand or make use of.
A research team in Italy examined bipolar patients during the time when they were in this stable, inter-episode phase. Next, under careful clinical supervision, they sleep-deprived these individuals for one night. Almost immediately, a large proportion of the individuals either spiraled into a manic episode or became seriously depressed.
Depression is not, as you may think, just about the excess presence of negative feelings. Major depression has as much to do with absence of positive emotions, a feature described as anhedonia: the inability to gain pleasure from normally pleasurable experiences, such as food, socializing, or sex.
“The best bridge between despair and hope is a good night’s sleep.”
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.
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.
the hippocampus—that key memory reservoir in the brain—is mysteriously unaffected by amyloid protein.
Those individuals with the highest levels of amyloid deposits in the frontal regions of the brain had the most severe loss of deep sleep and, as a knock-on consequence, failed to successfully consolidate those new memories.
the glymphatic system collects and removes dangerous metabolic contaminants generated by the hard work performed by neurons in your brain, rather like a support team surrounding an elite athlete.
Associated with the pulsing rhythm of deep NREM sleep comes a ten- to twentyfold increase in effluent expulsion from the brain.
The glial cells of the brain were shrinking in size by up to 60 percent during NREM sleep, enlarging the space around the neurons and allowing the cerebrospinal fluid to proficiently clean out the metabolic refuse left by the day’s neural activity.
One piece of toxic debris evacuated by the glymphatic system during sleep is amyloid protein—the poisonous element associated with Alzheimer’s disease.
Should you experimentally prevent a mouse from getting NREM sleep, keeping it awake instead, there is an immediate increase in amyloid deposits within the brain.
Inadequate sleep and the pathology of Alzheimer’s disease interact in a vicious cycle.
From this cascade comes a prediction: getting too little sleep across the adult life span will significantly raise your risk of developing Alzheimer’s disease.
Insufficient sleep is only one among several risk factors associated with Alzheimer’s disease. Sleep alone will not be the magic bullet that eradicates dementia. Nevertheless, prioritizing sleep across the life span may be a significant factor for lowering Alzheimer’s disease risk.
the shorter your sleep, the shorter your life.
Short sleep was associated with more than a 45 percent greater risk of fatal and nonfatal coronary heart disease within seven to twenty-five years from the start of the study.
Japanese study of 2,282 male workers. Over a fourteen-year period, sleeping less than six hours a night was associated with more than a three times greater risk of suffering a cardiovascular or coronary event, such as sudden cardiac death. This was relative to those sleeping 7 to 7.9 hours a night.
Adults forty-five years or older who sleep fewer than six hours a night are 200 percent more likely to have a heart attack or stroke during their lifetime, as compared with those sleeping seven to eight hours a night.
