Joanie March 18th, 2008
Excerpts from the article (bold mine):
So, it seems to be that practice does not quite make perfect; it¹s practice
with a night of sleep that makes perfect,” Walker says. “It’s this odd
notion that we all think in Western civilization that we have to stay awake
to get more done. And I think that’s simply not true. In fact, I think if
you have a good night of sleep, what you’ll find is that you can get more
done than if you simply stay awake…
So you’re saying that you take someone with a severe mental disorder and a
person without that disorder, but deprive them of sleep, and the brain scan
will look similar?” Stahl asks.
“Their pattern of brain activity was not dissimilar. So I think what it
forces us to do really now is to appreciate more significantly the role that
sleep may be playing in mental health and in psychiatric diseases…
You only need two seconds to have a lapse, in driving a car at 60 miles an
hour, to drift completely out lane,” Dinges says. “You’re off the road in
four seconds… The lapses are called “micro-sleeps,” and can even occur when people have their eyes open. What about turning up the radio, or opening the window to lower the temperature? “Studies show that all of that stuff people tend to do — slapping
themselves in the face, rolling the window down, radio up, singing –
they’re convinced it helps. But it’s only a matter of seconds or minutes.
And you can have a sudden sleep attack right in the midst of doing that,”
Dinges says.
THE SCIENCE OF SLEEP
CBS News
March 16, 2008
http://www.cbsnews.com/stories/2008/03/14/60minutes/main3939721.shtml
Human beings spend on average one third of their lives asleep. We know we
need to sleep but most of us have never really given a whole lot of thought
to why.
Why do we spend seven or eight hours a night immobile and unconscious? What
really happens inside our brains and bodies while we’re sleeping?
We’ve known the purpose of our other biological drives for hundreds of
years: we eat to give our bodies energy, we drink to keep hydrated, we
procreate to perpetuate the species - among other things. But what is the
biological purpose of sleep?
It turns out no one really knows for sure. As correspondent Lesley Stahl
reports, why we sleep is one of the biggest unanswered questions in all of
science, which is why researchers all over the country are doing studies and
coming up with some new and intriguing discoveries.
…………..
“We don’t sleep just to rest our tired bodies?” Stahl asks Matthew Walker,
the director of the Sleep and Neuroimaging Lab at the University of
California, Berkeley.
“Well, that’s been one of the long-standing theories. But I think what we’re
starting to understand is that sleep serves a whole constellation of
functions, plural,” Walker explains.
One thing that’s clear, says Walker, is that sleep is critical. In a series
of studies done back in the 1980s, rats were kept awake indefinitely. After
just five days, they started dying.
Walker says they started dying from sleep deprivation. “In fact, sleep is as
essential as food because they will die just about as quick from food
deprivation as sleep deprivation. So, it’s that necessary,” he says.
And it’s not just rats: every animal studied so far needs sleep, from the
elephant right down to the fruit fly. But that’s as far as the similarities
go. Some animals sleep 20 hours a day, others only two or three. And still
others sleep with half their brains at a time, all making it hard to figure
out what exactly it is about sleep that makes it so essential, and that, in
terms of evolution, makes it worth the risks.
“You wonder why we developed this if survival is the whole point. Because
you’re completely vulnerable when you’re lying there,” Stahl points out.
“Whatever the function of sleep, or the functions of sleep are, they seem to
be so important that evolution is willing to put us in that place of
potential danger by losing consciousness. It would be the biggest
evolutionary mistake if sleep does not serve some critical function,” Walker
says.
One of the most exciting new discoveries in the field of sleep research
involves learning and memory.
Five college students were subjects in one of Walker’s studies, and they had
been awake for more than 24 hours. He has found that students like these do
40 percent worse memorizing lists of words after a night without sleep. But
he has discovered something far more revolutionary about what happens when
we do sleep.
“Sleep, we’ve been finding, actually can enhance your memories, so that
you’ll come back the next day even better than where you were the day
before,” Walker tells Stahl.
To prove it, Walker put Stahl through a test he’s given to more than 400
study subjects. Stahl had to type a series of numbers — 4, 1, 3, 2, 4 –
over and over again with her left hand, making a new physical memory.
Some of Walker’s subjects learned this sequence in the morning, then were
tested 12 hours later to see how well they had learned. Their performance
remained essentially the same. But others learned it late in the day, then
were re-tested after a night of sleep. Their performance, as well as
Stahl’s, actually improved by at least 20 to 30 percent.
“So, it seems to be that practice does not quite make perfect; it¹s practice
with a night of sleep that makes perfect,” Walker says. “It’s this odd
notion that we all think in Western civilization that we have to stay awake
to get more done. And I think that’s simply not true. In fact, I think if
you have a good night of sleep, what you’ll find is that you can get more
done than if you simply stay awake.”
But what if you do sleep, just not enough?
That’s the focus of an NIH-funded study at the University of Pennsylvania’s
School of Medicine, where four paid volunteers get wired up with electrodes
and spend a week and a half sequestered in a dimly lit hospital suite. They
have to stay awake until 4 a.m., then are woken up at 8 a.m. for five nights
in a row. Then they’re given tests to measure the effects of what’s called
“chronic partial sleep deprivation.”
“So what are you finding? What kind of effect does just four hours a night
have?” Stahl asks David Dinges, the scientist in charge of the Penn study.
“Well, the first finding, and it stunned us, was there’s a cumulative
impairment that develops in your ability to think fast, to react quickly, to
remember things. And it starts right away,” Dinges says. “A single night at
four hours or five hours or even six, can in most people, begin to show
affects in your attention and your memory and the speed with which you
think. A second night it gets worse. A third night worse. Each day adds an
additional burden or deficit to your cognitive ability.”
“I’m stunned by you saying one night of just four or five hours sleep, and
your ability to function is already hurt,” Stahl remarks.
“But remember, we’re not allowing caffeine, and we’re not allowing physical
activity and bright light. And for most of us, probably a day or two or so,
you can get by taking these, what we call the counter measures, right? But,
at some point what these studies show is the impairments get so bad, that
there’s little to no rescue possible without getting more sleep,” Dinges
says.
Dinges told 60 Minutes that his subjects, like a young French woman named
Hacina, get to where it seems like they¹re moving through molasses.
“So, overall, how do you think not having enough sleep for five nights has
affected you?” Stahl asked Hacina.
“Well, my - I- I’m quiet - quieter, definitely,” she replied.
“And - and - uh- what else did you ask?” Hacina asked after a long pause,
seeming confused.
The testing for alertness and reaction time has real-world relevance.
Virginia Tech’s Transportation Institute did a study of what causes car
crashes. They got 241 volunteers to agree to have their cars wired with five
cameras each. Over a year’s time they found that driving drowsy was the
riskiest behavior of all.
“You only need two seconds to have a lapse, in driving a car at 60 miles an
hour, to drift completely out lane,” Dinges says. “You’re off the road in
four seconds. And those kinds of lapses and slowed reaction times begin to
appear fairly early.”
The lapses are called “micro-sleeps,” and can even occur when people have
their eyes open.
What about turning up the radio, or opening the window to lower the
temperature?
“Studies show that all of that stuff people tend to do — slapping
themselves in the face, rolling the window down, radio up, singing –
they’re convinced it helps. But it’s only a matter of seconds or minutes.
And you can have a sudden sleep attack right in the midst of doing that,”
Dinges says.
And it’s not just driving. Dinges has examined, sometimes as an expert
witness, the role of inadequate sleep in some of the world’s most well-known
accidents.
He thinks inadequate sleep may have contributed to the Exxon Valdez oil
spill, Chernobyl, the Three Mile Island disaster and the 2003 Staten Island
ferry crash.
60 Minutes checked. The Exxon Valdez spill happened after midnight with a
man at the helm who’d slept only four hours the night before; Chernobyl and
Three Mile Island also occurred late at night and involved human error. And
the assistant captain who crashed the Staten Island ferry into a pier,
killing 11, admitted that he felt exhausted before the accident.
“Many people want something associated with morals or management
orSalcohol,” Dinges remarks. “Those are far more glamorous. But, in reality,
many of these disasters involve poor judgments and slowed reactions at a
time when people were basically tired and made not complicated mistakes.
Simple ones. And that is the hallmark of sleep deprivation.”
Hacina, the sleep-deprived French woman in the Penn study, thought she was
maybe alert enough to give Stahl a lift.
“What really struck me is that she didn’t know how impaired she was. It was
clear, but she didn’t know,” Stahl remarks.
“That has been a finding in all of our studies. They tell you they’ve
adapted. They’re okay,” Dinges says.
Dinges says people who are chronically sleep deprived, like people who’ve
had too much to drink, often have no sense of their limitations. They
believe they’ve trained themselves. “I think it’s a convenient belief. For
the millions of people who don’t get enough sleep because their commute to
work is too long, or they spend too many hours at work, or they just want
this lifestyle of go, go, go, it’s convenient to say, ‘I’ve learned to live
without sleep.’ But you bring Oem into the laboratory — and we have an open
challenge to any CEO or anyone in the world, come into the laboratory — we
don’t see this adaptation,” he says.
One thing sleep researchers do see is that their sleep-deprived volunteers
often have mood swings: they get short-tempered, then become almost giddy,
sometimes within seconds.
“We took a group of young college undergraduates and we deprived them of
sleep for about 35 hours straight. And then we placed them inside a MRI
scanner and we showed them increasingly negative and disturbing images,”
says Matthew Walker, who devised a study to look at what was going on inside
their brains. “And what we found was that in those people who had a good
night of sleep, the control group, they showed a nice, modest, controlled
response in their emotional centers of the brain.”
“But, when we looked in the sleep deprived subjects, instead, what we found
is a hyperactive brain response,” he says.
And what’s more, in the sleep-deprived subjects, Walker discovered a
disconnect between that over-reacting amygdala (a region of the brain) and
the brain’s frontal lobe, the region that controls rational thought and
decision-making, meaning that the subjects’ emotional responses were not
being kept in check by the more logical seat of reasoning. It’s a problem
also found in people with psychiatric disorders.
“So you’re saying that you take someone with a severe mental disorder and a
person without that disorder, but deprive them of sleep, and the brain scan
will look similar?” Stahl asks.
“Their pattern of brain activity was not dissimilar. So I think what it
forces us to do really now is to appreciate more significantly the role that
sleep may be playing in mental health and in psychiatric diseases. And I
think that could be one of the futures of the field of sleep research,”
Walker replies.
Walker says most of us need seven and a half to eight hours of sleep every
night.
By almost all measures, we are sleeping less than ever before. In 1960, a
survey by the American Cancer Society asked one million Americans how much
sleep they were getting a night. The median answer was eight hours. Today
that number has fallen to 6.7 hours — that’s a decrease of more than 15
percent in less than a lifetime. And from what the scientists 60 Minutes met
are finding, we may be putting ourselves in a perilous situation.
Eve Van Cauter, an endocrinologist at the University of Chicago School of
Medicine, studies the effect of sleep on the body. At her lab, healthy,
young volunteers like Jonathan Mrock are paid to come one at a time and have
virtually every system in their bodies monitored while their sleep is
interfered with.
“We did a study where we restricted sleep to four hours per night for six
nights,” Van Cauter explains. “And we noticed that they were already in a
pre-diabetic state. And so, that was a big finding.”
The study’s subjects were on the road to diabetes in just six days, and
that¹s not all — they were also hungry. Van Cauter has made a radical
discovery: that lack of sleep may be contributing to the epidemic of obesity
in this country through the work of a hormone called leptin that tells your
brain when you¹re full.
“We observed that the volunteers, they actually had a drop in leptin
levels,” Van Cauter explains. “Leptin was telling the brain, ‘Time to eat.
We need more food.’”
“Even though they¹d eaten,” Stahl remarks.
“But in fact they had plenty of food,” Van Cauter agrees.
Several large-scale studies from all over the world have reported a link
between short sleep times and obesity, as well as heart disease, high blood
pressure, and stroke.
“I think it tells us that sleep deprivation is not a challenge for which
biology has wired us. There’s no other mammal that sleep deprives itself
than the human. So it is read by our biology as a stress,” Van Cauter says.
“You know, our attitude about sleep flies in the face of what you’re saying.
Because I think that ‘You don’t need as much sleep’ is looked upon as
something very positive,” Stahl remarks.
“It’s seen as a badge of honor,” Van Cauter agrees. “But you know I find it
amazing to see how many people are asleep within five minutes of boarding an
airplane at 11 o’clock in the morning. You know, sit down and boom. It
shouldn’t happen. A normal adult shouldn’t be falling asleep at 11 o’clock
in the morning, minutes after sitting in a small, uncomfortable airplane
seat. It just shows that, you know, people are exhausted.”
Jonathan the volunteer hasn’t been told exactly what is being tested during
his stay at the lab. He just knows on day five that he’s feeling kind of
groggy.
He thinks it’s the lights, but that’s because they aren’t telling him about
the sounds. Unbeknownst to Jonathan, each night when he falls into what
should be a restful slumber, he’s actually entering an eight and a half hour
battle. Jonathan’s opponent is Dr. Esra Tasali, a colleague of Van Cauter,
who is watching him and his brain waves from a small control room across the
hall and blasting sounds through speakers on both sides of his bed.
In this experiment, the idea is not to interfere with the quantity of
Jonathan’s sleep but the quality. Soon after he falls asleep, Jonathan’s
body naturally wants to enter what’s called “deep sleep,” but Tasali is
determined to stop him without waking him up. Every time his brain starts
producing what are called “delta waves,” indicating the start of deep sleep,
she searches her arsenal of sounds and “attacks.”
During a normal night, we cycle through different stages of sleep,
progressing from light into deep sleep, then into REM (Rapid eye movement),
or dream sleep, and back again. As we age, though, the amount of time we
spend in deep sleep decreases.
Van Cauter and Tasali are investigating a novel theory that some of the
health problems we typically associate with old age may in fact be caused by
the loss of deep sleep.
“We lose deep sleep at a very early age. So a young, healthy person may have
100 minutes of deep sleep, and at 50 years old it may be as little as 20
minutes. So it reallyS goes down very quickly,” Van Cauter explains.
Tasali’s goal is to turn 19-year-old Jonathan, sleep-wise, into a
70-year-old.
The next morning — 346 sounds later — it’s time for testing. Now
Jonathan’s going to have fat extracted from his body for analysis, go
through a PET scan to see how his brain is metabolizing sugar, and between
procedures, he¹s answering questions about how he feels. His doctors assure
60 Minutes that Jonathan will be fine once he goes back to his normal sleep
routine, but after four nights without deep sleep they have found that, like
prior study subjects, he is hungrier, less alert, and most importantly, his
body is no longer able to metabolize sugar effectively, putting him
temporarily at increased risk for Type 2 diabetes.
“We usually think of diabetes as something that’s a disease of old age. But
really it may be a disease of sleep deprivation,” Stahl remarks.
“I would say that sleep deprivation may be a new risk factor for diabetes,”
Van Cauter says. “Not just aging, not just being overweight or obese, not
just having a family history of diabetes, which are the three major risk
factors. But this is an added one. And we have really an epidemic of
diabetes now. And Type 2 diabetes is now occurring in children, in
adolescents. And, you know, adolescents and children too are also being
sleep deprived. Maybe high schoolers are amongst the most sleep deprived
individuals in our society, because they have an enormous sleep need - nine
to ten hours. Yet they sleep less than seven hours per night.”
She says this research proves we all need to rethink what we consider
essential for good health — that the diet and exercise formula also has to
include sleep.
So if lack of sleep impacts our appetite, our metabolism, our memory, and
how we age, is there anything it doesn’t affect? How about sex? Scientist
Scott McRobert at St. Joseph’s University in Philadelphia is asking that
very question, studying fruit flies.
Stahl watched as McRobert used a bizarre contraption to suck a male
drosophila (fruit fly) out of a vial and put him into a little dish with a
female.
McRobert gave Stahl a play-by-play of the action. “Okay. So now, the
female’s walking around the outside of the chamber,” McRobert explains. “And
the male’s in the center. And you see he’s orienting toward her, everywhere
she goes.”
“He’s following her. If you watch closely, he’ll touch her with his front
legs. It¹s hard to see, but he will. And he¹ll sing. Here comes the song,”
McRobert says.
Flies sing, he tells Stahl, by lifting one wing to the side and vibrating it
up and down.
McRobert is doing a study to see whether sleep-deprivation in fruit flies
affects mating. The two flies in the dish had regular amounts of sleep. “And
when he’s in the presence of a sexually attractive female, he’s just
courting and doing almost nothing else,” he says.
Eventually, the flies did mate.
But it was a different story when a pair of flies was brought together where
the male had been sleep deprived.
“You can actually see the difference. He was courting a second ago. But he
doesn’t stay with her,” McRobert points out.
McRobert told Stahl the sleep-deprived flies rarely if ever mate.
“Even though you’re not sure how to make an analogy to men, if any are
watching, nevertheless, this could be somewhat of a lesson,” Stahl remarks.
“If you want to take this to the level of humans. And this is something that
geneticists rarely do if they¹re smart. And I probably shouldn’t do it
either. But the take-home lesson is ‘Get enough sleep,’” McRobert says. “I
mean, the successful male drosophila is a drosophila that gets enough
sleep.”
So at least for now, it looks like we¹re stuck sleeping a third of our lives
away.
“Humans love to keep asking, ‘Can¹t we just get rid of sleep?’ If you had a
poll in the United States and said, ‘If we could safely eliminate half of
the time you sleep. And you wouldn’t suffer any deficit, you’d be good to
go.’ We could just magically make sleep go away. How many people would want
it? And I believe you’d find the population votes easily overwhelmingly for
it,” David Dinges predicts. “And yet I think the hedonic joy of sleeping and
the need for sleep and how good it feelsSI would have to say that
consciousness, wake-consciousness is probably a bit overrated.”
Asked if she thinks we’re going to figure out a way to get along with less
sleep, Eve Van Cauter tells Stahl, “I hope not.”
“You don’t think that’s where research should put its effort?” Stahl asks.
“You know, Lesley, my impression is that sleep affects so many aspects of
mental and physical function, that there’s not going to be one magic bullet
drug that will be able to compensate. Much better idea is simply to sleep an
hour more,” she says.
Well, what about an afternoon cat nap? Some new research is showing that
what counts is getting your seven and a half to eight hours total. So naps
do help. But not all the scientists are convinced that’s as good as sleeping
straight through the night.
………….
NHNE On Sleep & Naps:
http://www.nhne.org/news/NewsArticlesArchive/tabid/400/articleType/CategoryV
iew/categoryId/122/Health-Sleep.aspx
NHNE On Dreams & Inner Guidance:
http://www.nhne.org/news/NewsArticlesArchive/tabid/400/articleType/CategoryV
iew/categoryId/23/Other-Realms-Dreams–Inner-Guidance.aspx
