This fascinating transcript gives us some insight into the secrets of sleep. Enjoy!
Narration: With work going global, and shiftwork blurring day and night, we all feel the pressure - to sleep less and get away with it.
So can we?
Professor David Dinges: The scientific question is â€œis it OK to manipulate these basic, old processes. Shorten our sleep, engage in jetlag and shiftwork. And can we do it safely?
Narration: Here in the Philadelphia, weâ€™re about to enter the torture chambers of sleep deprivation research to find out.
Professor David Dinges: OK Fanny, time to wake up.
Narration: Itâ€™s 8 am and Fanny has had just 4 hours sleep, every night, for the last week.
This is the world famous University of Pennsylvania sleep laboratory, run by Professor David Dinges.
Professor David Dinges: Weâ€™re in the laboratory - low light The windows are blocked out so thereâ€™s no sunrise or sunset here, thereâ€™s continuous monitoring.
Narration: If it sounds like hell, it gets worse. Once awoken, the poor subjects are barraged with mental tests.
The scientists are looking at the effects of sleep debt â€“ what happens when weâ€™re chronically deprived of sleep.
Fanny Umm, Iâ€™m getting a little loopy.
Professor David Dinges: Our working memory begins to slow down. We also have problems with new and creative solutions. So cognitive slowness, errors under time pressure, are all hallmark features of increased sleep pressure. The remarkable thing is when you take a little sleep away, cut people down to four or five or six hours a night, after a week or ten days of this, theyâ€™re actually as impaired us someone who weâ€™ve kept awake for 48 hours.
Narration: Lack of sleep is as dangerous as alcohol behind the wheel.
But astonishingly, some people, known as Type Oneâ€™s, appear immune to sleep deprivation.
Professor David Dinges: To our absolute amazement approximately fifteen to twenty percent of people we study in the lab appear to have little to no response to sleep deprivation. Now they can go quite far, forty hours without sleep, and show no cognitive or physiologic response to it.
Narration: So what is so different about this kind of brain?
Here at the University of California, San Diego, thatâ€™s what Dr Sean Drummond has spent the last 15 years stealing peoples sleep to find out.
When most of us are sleep deprived and asked to think, our brains look like this.
Dr. Sean P.A. Drummond: OK so here we have subjects performing this test when they are well rested and on the right is the same group of subjects performing the test after 35 hours sleep deprivation. And we can see the brain is not responding normally at all.
Dr Jonica Newby: So the brainâ€™s almost shut down after sleep deprivation.
Dr. Sean P.A. Drummond: Yes, exactly.
Narration: But amazingly a type one brain looks very different.
Dr. Sean P.A. Drummond: Unlike what we just saw where the brain shuts down, the brain actually shows much more activation in these areas during sleep deprivation, plus some new areas that were not involved at all while rested,
Dr Jonica Newby: So some people can actually recruit more brain to compensate for the sleep deprivation?
Dr. Sean P.A. Drummond: Yeah, exactly.
Narration: Whatâ€™s going on?
Well, there are precedents in the animal kingdom. Plenty of animals thrive without 8 hours sleep.
In fact, sleep expert Professor Jerry Siegel has discovered some species â€“ like dolphins and killer whales â€“ hardly need it at all.
Professor Jerry Siegel: Well the most unusual aspect is they can be active continuously for days or weeks and they can have the brainwaves that look like sleep but only in half the brain at a time. And still behaving as if they were awake, they can dodge obstacles, swim accurately, and they seem quite responsive.
Dr Jonica Newby: That doesnâ€™t sound like sleep at all.
Professor Jerry Siegel: It doesnâ€™t look like sleep either.
Narration: Yet dolphins still manage to achieve sleepâ€™s core functions, such as:
Professor Jerry Siegel: During sleep protein synthesis is enhanced, so sleep is a great time for repairing damage to the body and particularly to the brain.
Narration: At the other end of the spectrum, rats need sleep so badly, they quickly die without it.
Professor Jerry Siegel: Itâ€™s pretty clear that some of the functions of sleep have been moved by evolution into waking. Because animals that sleep as little as two hours a day donâ€™t sleep more deeply than animals that sleep 20 hours a day. So clearly, whatever the functions are, are being accomplished in less time.
Narration: So if type one people are more like dolphins, can the rest of us train ourselves to be less like rats
Dr Jonica Newby: Is there any way I can learn to be the other kind of person?
Dr. Sean P.A. Drummond: Well unfortunately we think probably not.
Dr Jonica Newby: Thatâ€™s disappointing. (laugh)
Narration: It seems if youâ€™re a born rat, youâ€™ll have to find another way to join the rat race.
Well, that is why most of us turn to the Sunday sleep in. But does it actually work?
Back at the sleep lab, after a week of just 4 hours a night, Fanny is finally being allowed a ten hour sleep.
Fanny: Iâ€™m looking forward to the Sandman.
Dr Jonica Newby: Enjoy your rest.
Narration: In a world first, the team is trying to work out how much sleep we really need to recover from a working weekâ€™s worth of sleep debt.
Professor David Dinges: Now some of my colleagues joke and say â€œSo- so Dave what youâ€™re doing now by studying recovery sleep is youâ€™re trying to prove the need for the weekend.â€ And while that may seem trivial, it actually is imperative that we know what the days off the recovery sleep needs to be because the pressure in the world economically and global economies, is to have more people awake more of the time, and push, push, push
Narration: Scientists have assumed that by getting a huge catchup sleep once a week, people will get away with less sleep overall.
Dr Jonica Newby: Well Fanny, ten hours sleep. Whatâ€™s that like?
Fanny: Whoo hoo, I feel great.
Narration: But is she really?
Professor Dinges results show, contrary to popular belief, one night of even 10 hours is not enough to bring a person back to normal.
But the big problem is, theyâ€™ve discovered, people consistently lose the ability to realise just how mentally impaired they are.
Professor David Dinges: And so when maximally impaired after a week or so of sleep restriction they say, â€œIâ€™m doing pretty well now.â€ So we disconnect our actual functioning from our ability to introspect it and know it. That actually makes sleep restriction quite dangerous occupations where people need to be able to know what their impairment is.
Narration: The data are all pointing one way â€“ itâ€™s not possible to sleep less and get away with it.
Professor David Dinges: Thereâ€™s evidence that disregulation of sleep, loss of sleep, can led to increased mortality, obesity, and other health related problems.
Dr Jonica Newby: So you think society is pushing past our biological capacity.
Professor David Dinges: I think weâ€™re operating at the boundary for the bulk of society.
Narration: While dolphins are better at fighting it, and rats can try to outfox it, eventually we all have to pay.
And if we keep pushing life in the fast lane â€“ you have to wonder - at what point is the price too high?
Dr Jonica Newby: Good night.
Professor David Dinges
University of Pennsylvania School of Medicine
Dr. Sean P.A. Drummond
Psychiatry, UC San Diego
Professor Jerry Siegel
Reproduced from: http://www.abc.net.au/catalyst/stories/s1789852.htm (February 2009)