Going
without sleep for too long kills animals but scientists haven’t known
why. Newly published work suggests that the answer lies in an unexpected
part of the body.
Feeling dead tired? Scientists may finally be on the verge of learning why too little sleep is inevitably fatal.
Inside
a series of tubes in a bright, warm room at Harvard Medical School,
hundreds of fruit flies are staying up late. It has been days since any
of them have slept: The constant vibrations that shake their homes
preclude rest, cling as they might to the caps of the tubes for respite.
Not too far away in their own tubes live other sleepless flies,
animated with the calm persistence of those consigned to eternal day. A
genetic tweak to certain neurons in their brains keeps them awake for as
long as they live.
They do not live long. The shaken flies and the engineered flies both
die swiftly — in fact, the engineered ones survive only half as long as
well-rested controls. After days of sleeplessness, the flies’ numbers
tumble, then crash. The tubes empty out. The lights shine on.
We all know that we need sleep to be at our best. But profound sleep
loss has more serious and immediate effects: Animals completely deprived
of sleep die. Yet scientists have found it oddly hard to say exactly
why sleep loss is lethal.
Sleep is primarily seen as a neurological phenomenon, and yet when
deprived creatures die, they have a puzzlingly diverse set of failures
in the body outside the nervous system. Insufficient sleep in humans and
lab animals, if chronic, sets up health problems that surface over
time, such as heart disease, high blood pressure, obesity and diabetes.
But those conditions are not what slays creatures that are 100% sleep
deprived within days or weeks.
What does sleep do that makes it deadly to go without? Could
answering that question explain why we need sleep in the first place?
Under the pale light of the incubators in Dragana Rogulja’s lab at Harvard Medical School, sleepless flies have been living and dying as she pursues the answers.
On a cold morning this winter, Rogulja leaned over a tablet in her
office, her close-cropped dark hair framing a face of elfin intensity,
and flicked through figures to explain some of her conclusions. Rogulja
is a developmental neuroscientist by training, but she is not convinced
that the most fundamental effect of sleep deprivation starts in the
brain. “It could come from anywhere,” she said, and it might not look
like what most people expect.
She has findings to back up that intuition. Publishing today in the journal Cell,
she and her colleagues offer evidence that when flies die of
sleeplessness, lethal changes occur not in the brain but in the gut. The
indigo labyrinths of the flies’ small intestines light up with fiery
fuchsia in micrographs, betraying an ominous buildup of molecules that
destroy DNA and cause cellular damage. The molecules appear soon after
sleep deprivation starts, before any other warning signs; if the flies
are allowed to sleep again, the rosy bloom fades away. Strikingly, if
the flies are fed antioxidants that neutralize these molecules, it does
not matter if they never sleep again. They live as long as their rested
brethren.
The results suggest that one very fundamental job of sleep — perhaps
underlying a network of other effects — is to regulate the ancient
biochemical process of oxidation, by which individual electrons are
snapped on and off molecules in service to everything from respiration
to metabolism. Sleep, the researchers imply, is not solely the province
of neuroscience, but something more deeply threaded into the
biochemistry that knits together the animal kingdom.
More Fatal Than Starvation
The first studies to investigate total sleep deprivation had a maniacal quality
to them. In Rome in 1894, Maria Mikhailovna Manaseina, a Russian
biochemist, made a presentation at the International Congress of
Medicine about her experiments on 10 puppies. She and her lab assistants
had kept the dogs awake and in constant motion 24 hours a day; within
about five days, all the puppies had died. Sleep deprivation seemed to
kill puppies much more quickly than starvation, she reported: “The total
absence of sleep is more fatal for the animals than the total absence
of food.”
Autopsies revealed that the puppies’ tissues were in bad repair,
particularly in the brain, which was rife with hemorrhages, damaged
blood vessels and other gruesome features. Sleep, Manaseina concluded,
is not a useless habit. It does something profound for brain health
.
More all-day, all-night dog walking followed. In 1898 Lamberto Daddi,
an Italian researcher, published detailed drawings of the brains of
dogs that had been sleep-deprived; he reported apparent degenerative
damage in the brain, similar to that seen in dogs that had faced other
stressors. Around the same time, the psychiatrist Cesar Agostini kept
dogs in cages rigged with bells that jangled horribly whenever they
tried to lie down and sleep, and in the 1920s researchers in Japan did
something similar with cages studded with nails.
The studies, aside from their consistent cruelty, had a similar
weakness: They had no valid controls. The dogs had died and their
tissues looked abnormal — but was that truly because they had not slept?
Or was it because nonstop walks and stimulation are inherently
stressful? Separating the effects of sleeplessness from being kept on
your feet until it killed you seemed impossible.
The Turntable Cage
It took decades for scientists to return to the question in a serious way. In the 1980s, Allan Rechtschaffen, a sleep researcher at the University of Chicago celebrated for his pioneering work on narcolepsy, began to design experiments
that could separate the effects of overstimulation from those of
sleeplessness. He devised a rat cage in the form of a turntable
suspended over water. A divider ran down the middle, so animals could
live on either side while the turntable floor beneath them spun freely.
Into the device the experimenters put pairs of rats, one of which was
destined to be denied sleep. Whenever that rat tried to rest, the
scientists spun the table, knocking both rats into the water.
This setup ensured that although both rats fell into the water
equally often, the control rat could still catch some winks whenever the
rat denied sleep was active. In fact, control rats managed to sleep
about 70% as much as they normally would, suffering only mild sleep
deprivation. The unluckier experimental rats got less than 9%, almost
total sleep loss.
Both sets of rats were disturbed the same number of times. Both
suffered the stress of falling into the water and having to clamber back
out, dripping. But only the severely sleep-deprived rats began to
decline. Their fur grew rough and disheveled, and it went from white to a
mangy yellow. They developed lesions on their skin. They lost weight.
After around 15 days on average, they died. Rechtschaffen had discovered
a way to show that sleep loss itself really did kill.
For the graduate students running these experiments, the days were
long. “The lab was in an apartment building, so you’d have a bedroom
next to an animal testing room,” said Ruth Benca,
a professor of psychiatry at the University of California, Irvine who
worked with Rechtschaffen for some years. “They had bedrooms next to the
rooms where their animals were being deprived so they could monitor
around the clock.”
The work was challenging in other ways as well. “They were tough,
tough experiments to do, psychologically, to put an animal through
that,” said Paul Shaw,
one of Rechtschaffen’s later graduate students and now a professor of
neuroscience at Washington University in St. Louis. “The last seven days
of the experiment, you’re working with this cloud over your head.” When
his rats were just a day or two from death, the experimental protocol
called for him to let them sleep and observe their
electroencephalograms, or EEGs. Shaw recalls that as the monitor
exploded with life, announcing the animals’ long-awaited slumber, he
felt a weight fall from his shoulders. “To this day I can see it,” he
said, speaking of the EEG readout. “I could put it in a frame up on my
wall, and it could make me happy every time.”
But the work was also thrilling. “You have to believe in the outcome
to do it. There’s no other way,” Shaw said. He arrived at the lab after
students who had pioneered these experiments received their degrees and
left, but he still heard their stories at meetings, where they
reminisced about the excitement. “No one wanted to get their Ph.D.,” he
recalled, because if they could stay, “they all thought that tomorrow,
they’d discover the function of sleep.”
Confusing Causes of Death
Rechtschaffen’s experimental successes should have finally enabled
scientists to see how insufficient sleep kills, which might have led to
bigger insights into what makes sleep so indispensable. But when the
researchers performed autopsies on the animals, what they found mostly
just added to the confusion. There were few consistent differences
between the control rats and those that died from lack of sleep, and no
sign of what had killed them. The deprived rats were thin and had
enlarged adrenal glands, but that was about it. “No anatomical cause of
death was identified,” the researchers concluded.
Observations of the animals’ behavior showed something more
interesting. “Animals [chronically] sleep-deprived under these carefully
controlled conditions would increase their food intake two and three
times normal amounts, and lose weight,” said Carol Everson,
a professor of medicine and neurobiology at the Medical College of
Wisconsin who was one of Rechtschaffen’s graduate students. “We did all
sorts of metabolic studies to try to find out if there was an impairment
we could detect.”
There was a strong feeling in the sleep field, however, that answers
about sleep’s most basic functions would be found in the brain. John Allan Hobson, a prominent Harvard Medical School sleep researcher, had just published a paper in Nature with the title “Sleep is of the brain, by the brain and for the brain.” As Shaw recalled, “This captured the zeitgeist of the entire sleep community.”
Indeed, the vast preponderance of sleep research today still centers
on the brain and on subjects like cognitive impairment. Sleep loss does
alter metabolism in humans — there are connections to diabetes and
metabolic syndrome — but public health researchers are often the only
ones who concern themselves with it. Those looking to understand the
fundamental purpose of sleep rarely seek answers in metabolism or other
chemical processes.
Reactive Oxygen Species
The neurons involved in regulating sleep are a focus of Rogulja’s
work. But the fact that sleep loss impairs circulation, digestion, the
immune system and metabolism made her curious about whether these were
downstream effects of neurological problems, or if they were
independent. “It seems like it can’t be all about the brain,” she said.
She knew about the Rechtschaffen experiments — “real classics” — and
that there had been few follow-ups. Once it was established that total
sleep loss kills, using deprivation to study sleep’s purpose had fallen
by the wayside. In the intervening decades, however, fruit flies had
become a major model organism in the sleep field, because their genetics
are widely understood and easy to manipulate and they are inexpensive
to keep in the lab. Many sleep discoveries first made in flies have been
verified in mammals. With the rise of flies as proven test subjects,
when Rogulja became curious about terminal sleep deprivation, it again
seemed like a plausible thing to study.
When the postdoctora researcher Alexandra Vaccaro
arrived at Rogulja’s lab in 2016, the two came up with a plan. First,
from other laboratories they obtained flies genetically engineered to
have temperature-sensitive channels in certain neurons. Above 28 degrees
Celsius, the channels opened and stayed open, keeping the neurons
activated and the flies awake. With the channels closed, the flies
enjoyed normal 110-day life spans. With the channels open, they started
dying of total sleep deprivation after only 10 days or so, and they were
all dead within 20 days.
A first-of-its-kind study from Michigan State found that a good night’s sleep does adolescents good – beyond helping them stay awake in class. Adequate sleep can help teens navigate challenging social situations.
Newswise — A new Michigan State
University study found that a good night’s sleep does adolescents good –
beyond helping them stay awake in class. Adequate sleep can help teens
navigate challenging social situations.
The study, which focused
on ninth grade students, found that adequate sleep allowed students to
cope with discrimination and challenges associated with ethnic or racial
bias. It also helps them problem-solve more effectively and seek peer
support when faced with hardships.
“Findings of this study have
important implications,” said Yijie Wang, assistant professor of human
development and family studies at MSU. “Understanding how sleep helps
adolescents negotiate social challenges may consequently elucidate how
promoting sleep may improve adolescent adjustment during high school and
beyond.”
Published in Child Development, this is the first study to identify the timing in which sleep helps with adolescents cope with stress.
Compared
to adults and children, high school students are particularly at risk
for insufficient sleep due to early school times, busy schedules and
increased social stressors. The transition to high school also
introduces more diversity to their social environment and relationships.
Via
this study, Wang and co-author Tiffany Yip of Fordham University wanted
to pinpoint the effect sleep has on coping with discrimination. They
found that if a teen has a good night of sleep, they are able to cope
with harsh experiences – like discrimination – better.
“This study
did not treat sleep as a consequence of discrimination,” Wang said.
“However, our team did identify the influence of discrimination on
same-day sleep in other studies. These studies showed that, on days when
adolescents experienced ethnic or racial discrimination, they slept
less and also took longer to actually fall asleep.”
Participants
in the study wore an actigraphy watch, which tracked physical activities
in one-minute intervals and determined their sleep-wake state, every
day for two weeks. The students were also asked to complete a survey
each day before bed, reporting their daytime experiences such as ethnic
or racial discrimination, how they responded to stress and their
psychological well-being.
A surprising finding in the study was
that peers, not parents, were the immediate support that help
adolescents cope with discrimination.
“Compared to parents, peers
are likely to be witnessing and involved in adolescents’ experiences of
ethnic or racial discrimination on a daily basis,” Wang said. “As such,
they’re more of an immediate support that backs up adolescents and
comforts them when discrimination occurs.”
Still, parents have an
important role in helping their children cope with both sleep and social
situations. Beyond getting the recommended eight hours, the quality of
sleep is just as important. That includes having a regular bedtime,
limiting media use and providing a quiet, less crowded sleep
environment.
While encouraging good sleep habits in adolescents
can be a struggle, said Wang that the benefits of a routine help them
cope with the challenges of life in high school and beyond.
“The
promotive effect of sleep is so consistent,” said Wang. “It reduces how
much adolescents ruminate, it promotes their problem solving and it also
helps them to better seek support from their peers.”
Worth trying to see how much healthier your life can be:
by DailyHealthPost
On
average, a human adult brain weighs about 3 pounds (1,300-1,400 g),
which is roughly 2% of your total body weight (not counting excess body
fat).
Your brain is responsible for almost every function in your
body. This includes anything that has to do with regulating hormones,
breathing, circadian rhythm, muscle control, heart beating,
coordination, critical thinking, emotions and much more.
It
goes without saying that the brain is one of the most energy demanding
organ in your body. It’s estimated that the brain by itself eats up
almost 20% of your body’s total calorie intake. And that number can vary
based on age, gender, size and how much brain power you actually use
throughout the day.
Since the brain is responsible for so many things, you’ll want to have it work at its optimum performance until The Big Sleep.
The following are ten common practices you may be doing that go against that goal.
Sleep deprivation can be dangerous to health. Over a long period it undermines the Immune System and causes all sorts of health problems.
Even
one night of too little sleep may lead to unwanted behavior at work the
next day, such as acting rude toward co-workers, theft or going home
early without notifying the boss
Poor
sleep may make it harder for people to stop engaging in such behaviors,
as well as to overcome feelings of failure when displaying the
undesirable behaviors
Employees’ “misbehaving” at work adds up, to the tune of $200 billion a year in the U.S. alone
People often don't want to acknowledge that sleep deprivation can be dangerous and undermine the Immune System considerably. This is why I felt this post to be of interest because, in our hectic lives, we often pay little attention to the lack of sleep.
While you sleep, your body is conducting countless activities, including growth and cell repair. It also works on restoring energy and nutrients to worn out muscles and tissues (1).
Sleep also balances out hormones and supports your immune system while working to supporting memory function.
That’s why poor sleep can leave you feeling not only groggy and cranky, but also less focused and more forgetful.
Interesting facts in this article for better sleep.
Exposure
to bright light first thing in the morning stops production of the
sleep-inducing hormone melatonin and signals to your body that it’s time
to wake up
Exercise
leads to better sleep at night; if you can’t fit in a workout in the
morning, a workout in the early evening may also help you sleep
If you’re a coffee drinker, take your last caffeinated sip in the early afternoon
We all know how important sleep is, yet so many people ignore the fact and believe that they can get away with little sleep. We therefore punish our body and then expect it to function in top form. This needs a serious re-think:
Based
on studies investigating how much sleep people need to maintain their
health, an expert panel concluded that most adults need right around
eight hours per night
About
40 percent of Americans are sleep deprived, which can increase your risk
for accidents, weight gain, chronic diseases, reduced sex drive, poor
cognitive function, and memory loss
Sleep
is essential for cementing events into long-term memory, and for making
sense of your life. During sleep your brain extracts the gist of what
happened during the day, and fosters new insights
Sleep deprication can seriously undermine the Immune Sytem which means it's wise to ensure healthy and plenty of sleep. It can lead not only to colds but other more serious conditions.
Sleeping less than six hours per night can increase your risk of catching a cold by 400 percent
Sleep
deprivation and stress have the same effect on your immune system; both
raise white blood cell counts, which is typically a sign of disease
Helpful
tips and novel tools to help you optimize your sleep, as well as
additional guidelines for cold and flu prevention are included
