Thursday, May 20, 2010

TSA Sham Behavioral Science?

TSA's Program to Spot Terrorists a $200M Sham?
Gov't Accountability Office Finds Army of Specially Trained "Behavior Detection" Agents Failed to Stop Terrorists
By Armen Keteyian, WASHINGTON, May 19, 2010

(CBS) Times Square bombing suspect Faisal Shahzad was arrested after he boarded a plane headed for Dubai, though the government is spending millions each year on a program that's supposed to spot terrorists before they reach the gate. As CBS News chief investigative correspondent Armen Keteyian reports, the program doesn't seem to be working.

There's a hidden layer of airport security most people don't know about. It's called "behavior detection," and involves specially trained Transportation Security Administration employees whose primary mission is to spot terrorists.

They look for unique facial expressions and body language that may identify a potential threat. About 3,000 of these officers work at 161 U.S. airports -- costing taxpayers nearly $200 million in 2009. This year, the TSA asked Congress for $20 million more to expand the program.

But CBS News has learned that the program is failing to catch terrorists. It's never even caught one.

In fact, sources tell CBS News a Government Accountability Office investigation is raising serious questions about the program.

The GAO uncovered at least 16 individuals later accused of involvement in terrorist plots flew 23 different times through U.S. airports since 2004. Yet none were stopped by TSA behavior detection officers working at those airports.

"It's a disgrace," said aviation security analyst Charles Slepian. "Why didn't they stop them? If it worked, you would catch them."

Scientists are split over whether it's even possible to recognize terrorists simply by behavior detection. A 2008 report found no evidence it works.

"TSA is doing a number of things in the area of behavior detection and I personally think that some of them are shams," said Stephen Fienberg, a professor at Carnegie Mellon University.

In a statement Wednesday, the TSA called the program a "vital layer" of security, "based in science," that has resulted in more than 1,700 arrests for "illegal activities" like drug smuggling.

The report based on the GAO investigation is due out Thursday. It will recommend across-the-board improvements in the program - ones the TSA is expected to accept.

Thursday, August 30, 2007

Face Police

Patti Davis: At the Airport, You Better Smile
‘Behavior Detection Officers’ are now watching passengers’ facial expressions for signs of danger. It’s a new level of absurdity for America.
By Patti Davis, Special to Newsweek, Updated: 11:40 a.m. CT Aug 16, 2007

Aug. 16, 2007 - It was bound to happen. Now even a frown or grimace can get you into trouble with The Man.

“Specially trained security personnel” will be watching passengers for “micro-expressions” that will reveal treacherous agendas and insidious intentions at airports around the country. These agents, who may literally hold your fate in their hands have been given a lofty, Orwellian name: "Behavior Detection Officers."

Did anyone ever doubt that George Orwell’s prophecies in “1984” would arrive? In that novel, he wrote, “You had to live—did live, from habit that became instinct—in the assumption that every sound you made was overheard and, except in darkness, every movement scrutinized.”

In the study of “micro-expressions”—yes, it is actually a field of study and there are some who are arrogant enough to call it a science—it has been decided that when people wish to conceal emotions, the truth of their feelings is revealed in facial flashes. These experts have determined that fear and disgust are the key things to look for because they can hint of deception.

Let’s see, fear and disgust in an airport? I’m frightened and disgusted weeks before I have to show up at an airport. In fact, I’ve pretty much sworn off the whole idea of going anywhere by airplane. It’s bad enough that I might be trapped in a crowded plane with no food or water and nonworking toilets for hours; now there are security agents interpreting our facial expressions. The face police, in place at more than a dozen U.S. airports already, aren’t identified as such. But the watcher could be at curbside baggage, the ticket counter or near the metal detectors and X-ray machines. The Transportation Security Administration hopes to have as many as 500 Behavior Detection Officers on the job by the end of 2008.

But what about the woman who is getting on a plane to see a dying relative? Or the man who is traveling to another state to see a cancer specialist in a last bid for extending his life? What about the guy who just had a fight with his spouse and now worries that a plane crash would mean their last words were in anger? We’ve all had the experience of having a bad day, being in a rotten mood—especially at the airport, which has become a modern-day chamber or horrors. On those days, doesn’t it seem like everyone we meet looks sour and unpleasant? The opposite is also true. When we’re happy and joyful, we look at others and see happiness in them. Or even if we don’t, we look at them kindly and with compassion. It’s human nature to look at others through the lens of our own reality.

Here’s where it gets really absurd. Apparently, these Behavior Detection Officers work in pairs. One scenario is that an officer might move in to “help” a passenger retrieve their belongings after they’ve been screened. And then the officer will ask where the passenger is headed. If the passenger’s reaction sets off alarm bells in the officer’s well-trained mind, another officer will move in and detain them. Let’s be really clear here. If a stranger moved in on me like that, I’d tell that person to go to hell, throw in a few other expletives for good measure and probably give them the finger as I stomped off. Of course, I wouldn’t be stomping very far.

So while TSA employees are confiscating our scissors and water bottles, they’re going to secretly be staring at us, looking for some telltale sign of terrorist intent in a grimace, a sigh, a crinkled nose? Who knows what? In the end, the Behavior Detection Officers are the ones who are really acting suspicious. Which is the truth of the matter anyway.

Monday, January 15, 2007


Excerpt: "Born on a Blue Day," by Daniel Tammet

A Man With Savant Syndrome Describes How His Mind Works

Jan. 15, 2007

Born with a rare condition called Savant Syndrome, Daniel Tammet sees the world like few other people.

To Tammet, numbers have shapes, emotions have colors, and math is as easy as blinking. He can learn to speak a language fluently from scratch in a week and has a complusive need for order and routine.

In "Born on a Blue Day: A Memoir of Aspergers and an Extraordinary Mind," Tammet lets readers in on how his mind works. Not only does "Born on a Blue Day" provide a a fascinating portrayl of a man with unique talents, it also offers insight into the power of the human brain.

Read an Excerpt from "Born on a Blue Day" below:

Blue Nines and Red Words

I was born on January 31, 1979 -- a Wednesday. I know it was a Wednesday, because the date is blue in my mind and Wednesdays are always blue, like the number 9 or the sound of loud voices arguing. I like my birth date, because of the way I'm able to visualize most of the numbers in it as smooth and round shapes, similar to pebbles on a beach. That's because they are prime numbers: 31, 19, 197, 97, 79 and 1979 are all divisible only by themselves and 1. I can recognize every prime up to 9,973 by their "pebble-like" quality. It's just the way my brain works.

I have a rare condition known as savant syndrome, little known before its portrayal by actor Dustin Hoffman in the Oscar-winning 1988 film Rain Man. Like Hoffman's character, Raymond Babbitt, I have an almost obsessive need for order and routine which affects virtually every aspect of my life.

For example, I eat exactly 45 grams of porridge for breakfast each morning; I weigh the bowl with an electronic scale to make sure. Then I count the number of items of clothing I'm wearing before I leave my house. I get anxious if I can't drink my cups of tea at the same time each day. Whenever I become too stressed and I can't breathe properly, I close my eyes and count. Thinking of numbers helps me to become calm again.

Numbers are my friends, and they are always around me. Each one is unique and has its own personality. The number 11 is friendly and 5 is loud, whereas 4 is both shy and quiet -- it's my favorite number, perhaps because it reminds me of myself. Some are big -- 23, 667, 1,179 -- while others are small: 6, 13, 581. Some are beautiful, like 333, and some are ugly, like 289. To me, every number is special.

No matter where I go or what I'm doing, numbers are never far from my thoughts. In an interview with talk show host David Letterman in New York, I told David he looked like the number 117 -- tall and lanky. Later outside, in the appropriately numerically named Times Square, I gazed up at the towering skyscrapers and felt surrounded by 9s -- the number I most associate with feelings of immensity.

Scientists call my visual, emotional experience of numbers synesthesia, a rare neurological mixing of the senses, which most commonly results in the ability to see alphabetical letters and/or numbers in color. Mine is an unusual and complex type, through which I see numbers as shapes, colors, textures and motions. The number 1, for example, is a brilliant and bright white, like someone shining a flashlight into my eyes. Five is a clap of thunder or the sound of waves crashing against rocks. Thirty-seven is lumpy like porridge, while 89 reminds me of falling snow.

Probably the most famous case of synesthesia was the one written up over a period of thirty years from the 1920s by the Russian psychologist A. R. Luria of a journalist called Shereshevsky with a prodigious memory. "S," as Luria called him in his notes for the book The Mind of a Mnemonist, had a highly visual memory which allowed him to "see" words and numbers as different shapes and colors. "S" was able to remember a matrix of 50 digits after studying it for three minutes, both immediately afterwards and many years later. Luria credited Shereshevsky's synesthetic experiences as the basis for his remarkable short- and long-term memory.

Using my own synesthetic experiences since early childhood, I have grown up with the ability to handle and calculate huge numbers in my head without any conscious effort, just like the Raymond Babbitt character. In fact, this is a talent common to several other real-life savants (sometimes referred to as "lightning calculators"). Dr. Darold Treffert, a Wisconsin physician and the leading researcher in the study of savant syndrome, gives one example, of a blind man with "a faculty of calculating to a degree little short of marvelous" in his book Extraordinary People:

When he was asked how many grains of corn there would be in any one of 64 boxes, with 1 in the first, 2 in the second, 4 in the third, 8 in the fourth, and so on, he gave answers for the fourteenth (8,192), for the eighteenth (131,072) and the twenty-fourth (8,388,608) instantaneously, and he gave the figures for the forty-eighth box (140,737,488,355,328) in six seconds. He also gave the total in all 64 boxes correctly (18,446,744,073,709,551, 616) in forty-five seconds.

My favorite kind of calculation is power multiplication, which means multiplying a number by itself a specified number of times. Multiplying a number by itself is called squaring; for example, the square of 72 is 72 x 72 = 5,184. Squares are always symmetrical shapes in my mind, which makes them especially beautiful to me. Multiplying the same number three times over is called cubing or "raising" to the third power. The cube, or third power, of 51 is equivalent to 51 x 51 x 51 = 132,651. I see each result of a power multiplication as a distinctive visual pattern in my head.

As the sums and their results grow, so the mental shapes and colors I experience become increasingly more complex. I see 37's fifth power -- 37 x 37 x 37 x 37 x 37 = 69,343,957 -- as a large circle composed of smaller circles running clockwise from the top around.

When I divide one number by another, in my head I see a spiral rotating downwards in larger and larger loops, which seem to warp and curve. Different divisions produce different sizes of spirals with varying curves. From my mental imagery I'm able to calculate a sum like 13 ÷ 97 (0.1340206...) to almost a hundred decimal places.

I never write anything down when I'm calculating, because I've always been able to do the sums in my head, and it's much easier for me to visualize the answer using my synesthetic shapes than to try to follow the "carry the one" techniques taught in the textbooks we are given at school. When multiplying, I see the two numbers as distinct shapes. The image changes and a third shape emerges -- the correct answer. The process takes a matter of seconds and happens spontaneously. It's like doing math without having to think.

Different tasks involve different shapes, and I also have various sensations or emotions for certain numbers. Whenever I multiply with 11 I always experience a feeling of the digits tumbling downwards in my head. I find 6s hardest to remember of all the numbers, because I experience them as tiny black dots, without any distinctive shape or texture. I would describe them as like little gaps or holes. I have visual and sometimes emotional responses to every number up to 10,000, like having my own visual, numerical vocabulary.

And just like a poet's choice of words, I find some combinations of numbers more beautiful than others: ones go well with darker numbers like 8s and 9s, but not so well with 6s. A telephone number with the sequence 189 is much more beautiful to me than one with a sequence like 116.

This aesthetic dimension to my synesthesia is something that has its ups and downs. If I see a number I experience as particularly beautiful on a shop sign or a car license plate, there's a shiver of excitement and pleasure. On the other hand, if the numbers don't match my experience of them -- if, for example, a shop sign's price has "99 pence" in red or green (instead of blue) -- then I find that uncomfortable and irritating.

It is not known how many savants have synesthetic experiences to help them in the areas they excel in. One reason for this is that, like Raymond Babbitt, many suffer profound disability, preventing them from explaining to others how they do the things that they do. I am fortunate not to suffer from any of the most severe impairments that often come with abilities such as mine.

Like most individuals with savant syndrome, I am also on the autistic spectrum. I have Asperger's syndrome, a relatively mild and high-functioning form of autism that affects around 1 in every 300 people in the United Kingdom. According to a 2001 study by the U.K.'s National Autistic Society, nearly half of all adults with Asperger's syndrome are not diagnosed until after the age of sixteen. I was finally diagnosed at age twenty-five following tests and an interview at the Autism Research Centre in Cambridge.

Autism, including Asperger's syndrome, is defined by the presence of impairments affecting social interaction, communication, and imagination (problems with abstract or flexible thought and empathy, for example). Diagnosis is not easy and cannot be made by a blood test or brain scan; doctors have to observe behavior and study the individual's developmental history from infancy.

People with Asperger's often have good language skills and are able to lead relatively normal lives. Many have above-average IQs and excel in areas that involve logical or visual thinking. Like other forms of autism, Asperger's is a condition affecting many more men than women (around 80 percent of autistics and 90 percent of those diagnosed with Asperger's are men). Single-mindedness is a defining characteristic, as is a strong drive to analyze detail and identify rules and patterns in systems. Specialized skills involving memory, numbers, and mathematics are common. It is not known for certain what causes someone to have Asperger's, though it is something you are born with.

For as long as I can remember, I have experienced numbers in the visual, synesthetic way that I do. Numbers are my first language, one I often think and feel in. Emotions can be hard for me to understand or know how to react to, so I often use numbers to help me. If a friend says they feel sad or depressed, I picture myself sitting in the dark hollowness of number 6 to help me experience the same sort of feeling and understand it. If I read in an article that a person felt intimidated by something, I imagine myself standing next to the number 9. Whenever someone describes visiting a beautiful place, I recall my numerical landscapes and how happy they make me feel inside. By doing this, numbers actually help me get closer to understanding other people.

Sometimes people I meet for the first time remind me of a particular number and this helps me to be comfortable around them. They might be very tall and remind me of the number 9, or round and remind me of the number 3. If I feel unhappy or anxious or in a situation I have no previous experience of (when I'm much more likely to feel stressed and uncomfortable), I count to myself. When I count, the numbers form pictures and patterns in my mind that are consistent and reassuring to me. Then I can relax and interact with whatever situation I'm in.

Thinking of calendars always makes me feel good, all those numbers and patterns in one place. Different days of the week elicit different colors and emotions in my head: Tuesdays are a warm color while Thursdays are fuzzy. Calendrical calculation -- the ability to tell what day of the week a particular date fell or will fall on -- is common to many savants. I think this is probably due to the fact that the numbers in calendars are predictable and form patterns between the different days and months. For example, the thirteenth day in a month is always two days before whatever day the first falls on, excepting leap years, while several of the months mimic the behavior of others, like January and October, September and December, and February and March (the first day of February is the same as the first day of March). So if the first of February is a fuzzy texture in my mind (Thursday) for a given year, the thirteenth of March will be a warm color (Tuesday).

In his book The Man Who Mistook His Wife for a Hat, writer and neurologist Oliver Sacks mentions the case of severely autistic twins John and Michael as an example of how far some savants are able to take calendrical calculations. Though unable to care for themselves (they had been in various institutions since the age of seven), the twins were capable of calculating the day of the week for any date over a 40,000-year span.

Sacks also describes John and Michael as playing a game that involved swapping prime numbers with each other for hours at a time. Like the twins, I have always been fascinated by prime numbers. I see each prime as a smooth-textured shape, distinct from composite numbers (non-primes) that are grittier and less distinctive. Whenever I identify a number as prime, I get a rush of feeling in my head (in the front center) which is hard to put into words. It's a special feeling, like the sudden sensation of pins and needles.

Sometimes I close my eyes and imagine the first thirty, fifty, hundred numbers as I experience them spatially, synesthetically. Then I can see in my mind's eye just how beautiful and special the primes are by the way they stand out so sharply from the other number shapes. It's exactly for this reason that I look and look and look at them; each one is so different from the one before and the one after. Their loneliness among the other numbers makes them so conspicuous and interesting to me.

There are moments, as I'm falling into sleep at night, that my mind fills suddenly with bright light and all I can see are numbers -- hundreds, thousands of them -- swimming rapidly over my eyes. The experience is beautiful and soothing to me. Some nights, when I'm having difficulty falling asleep, I imagine myself walking around my numerical landscapes. Then I feel safe and happy. I never feel lost, because the prime number shapes act as signposts.

Mathematicians, too, spend a lot of time thinking about prime numbers, in part because there is no quick or simple method for testing a number to see whether or not it is prime. The best known is called "the Sieve of Eratosthenes" after an ancient Greek scholar, Eratosthenes of Cyrene. The sieve method works in this way: Write out the numbers you want to test, for example 1 to 100. Starting with 2 (1 is neither prime nor composite), cross out every second number: 4, 6, 8...up to 100. Then move to 3 and cross out every third number: 6, 9, 12...then move to four and cross out every fourth number: 8, 12, 16...and so on, until you are left with only a few numbers that do not ever get crossed out: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31...These are the prime numbers; the building blocks of my numerical world.

My synesthesia also affects how I perceive words and language. The word ladder, for example, is blue and shiny, while hoop is a soft, white word. The same thing happens when I read words in other languages: jardin, the French word for "garden," is a blurred yellow, while hnugginn -- Icelandic for "sad" -- is white with lots of blue specks. Synesthesia researchers have reported that colored words tend to obtain their colors from the initial letter of the word, and this is generally true for me: yogurt is a yellow word, video is purple (perhaps linked with violet) and gate is green. I can even make the color of a word change by mentally adding initial letters to turn the word into another: at is a red word, but add the letter H to get hat and it becomes a white word. If I then add a letter T to make that, the word's color is now orange. Not all words fit the initial-letter pattern: words beginning with the letter A, for example, are always red and those beginning with W are always dark blue.

Some words are perfect fits for the things they describe. A raspberry is both a red word and a red fruit, while grass and glass are both green words that describe green things. Words beginning with the letter T are always orange like a tulip or a tiger or a tree in autumn, when the leaves turn to orange.

Conversely, some words do not seem to me to fit the things they describe: geese is a green word but describes white birds (heese would seem a better choice to me), the word white is blue while orange is clear and shiny like ice. Four is a blue word but a pointy number, at least to me. The color of wine (a blue word) is better described by the French word vin, which is purple.

Seeing words in different colors and textures aids my memory for facts and names. For example, I remember that the winning cyclist of each stage of the Tour de France wins a yellow jersey (not green or red or blue), because the word jersey is yellow to me. Similarly, I can remember that Finland's national flag has a blue cross (on a white background) because the word Finland is blue (as are all words beginning with the letter F). When I meet someone for the first time I often remember their name by the color of the word: Richards are red, Johns are yellow, and Henrys are white.

It also helps me to learn other languages quickly and easily. I currently know ten languages: English (my native language), Finnish, French, German, Lithuanian, Esperanto, Spanish, Romanian, Icelandic and Welsh. Associating the different colors and emotions I experience for each word with its meaning helps bring the words to life. For example, the Finnish word tuli is orange to me and means "fire." When I read or think about the word I immediately see the color in my head, which evokes the meaning. Another example is the Welsh word gweilgi, which is a green and dark blue color and means "sea." I think it is an extremely good word for describing the sea's colors. Then there is the Icelandic word rökkur, which means "twilight" or "dusk." It is a crimson word and when I see it, it makes me think of a blood red sunset.

I remember as a young child, during one of my frequent trips to the local library, spending hours looking at book after book trying in vain to find one that had my name on it. Because there were so many books in the library, with so many different names on them, I'd assumed that one of them -- somewhere -- had to be mine. I didn't understand at the time that a person's name appears on a book because he or she wrote it. Now that I'm twenty-six I know better. If I were ever going to find my book one day, I was going to have to write it first.

Writing about my life has given me the opportunity to get some perspective on just how far I've come, and to trace the arc of my journey up to the present. If someone had told my parents ten years ago that I would be living completely independently, with a loving relationship and a career, I don't think they would have believed it and I'm not sure I would have either. This book will tell you how I got there.

My younger brother Steven has recently been diagnosed with the same form of high-functioning autism that I have. At nineteen, he is going through a lot of the challenges that I too faced while growing up, from problems with anxiety and loneliness to uncertainty about the future. When I was a child, doctors did not know about Asperger's syndrome (it was not recognized as a unique disorder until 1994) and so for many years I grew up with no understanding of why I felt so different from my peers and apart from the world around me. By writing about my own experiences of growing up on the autistic spectrum, it is my hope that I can help other young people living with high-functioning autism, like my brother Steven, to feel less isolated and to have confidence in the knowledge that it is ultimately possible to lead a happy and productive life. I'm living proof of that.

Tuesday, December 20, 2005

sleep books via Circadiana

recommendations for books on biological clocks, circadian rhythms and sleep via the fine blog Circadiana.

Tuesday, November 08, 2005

critter sleep

Down for the Count
By CARL ZIMMER, The New York Times, November 8, 2005

In a laboratory at Indiana State University, a dozen green iguanas sprawl tranquilly in terrariums. They while away the hours basking under their heat lamps, and at night they close both eyes - or sometimes just one. They lead comfortable lives pretty much indistinguishable from any ordinary pet iguana, except for one notable exception: the bundles of brain-wave recording wires that trail from their heads.

A team of scientists at Indiana State would like to know what happens in the brains of the iguanas when the lights go out. Do they sleep as we do? Do they shut the whole brain down, for example, or can they keep one half awake?

These scientists in Terre Haute hope the iguanas will also help shed some light on an even more fundamental question: why sleep even exists.

"Sleep has attracted a tremendous amount of attention in science, but we really don't know what sleep is," said Steven Lima, a biologist at Indiana State.

Dr. Lima belongs to a small but growing group of scientists who are pushing sleep research deep into the animal kingdom. They suspect that most animal species need to sleep, suggesting that human slumber has an evolutionary history reaching back over half a billion years.

Today animals sleep in many different ways: brown bats for 20 hours a day, for example, and giraffes for less than 2. To understand why people sleep the way they do, scientists need an explanation powerful enough to encompass the millions of other species that sleep as well.

"One of the reasons we don't understand sleep is that we haven't taken this evolutionary perspective on it," Dr. Lima said.

Sleep was once considered unique to vertebrates, but in recent years scientists have found that invertebrates likes honeybees and crayfish sleep, as well. The most extensive work has been carried out on fruit flies. "They rest for 10 hours a night, and if you keep them awake longer, they need to sleep more," said Dr. Giulio Tononi, a psychiatrist at the University of Wisconsin.

The parallels between fruit flies and humans extend even to their neurons. The two species produce, during part of the night, low-frequency electrical activity known as slow-wave sleep. "The flies surprised us with how close they were in many ways," Dr. Tononi said.

Discovering sleep in vertebrates and invertebrates alike has led scientists to conclude that it emerged very early in animal evolution - perhaps 600 million years ago. "What we're doing in sleeping is a very old evolutionary phenomenon," Dr. Lima said.

Scientists have offered a number of ideas about the primordial function of sleep. Dr. Tononi believes that it originally evolved as a way to allow neurons to recover from a hard day of learning. "When you're awake you learn all the time, whether you know it or not," he said.

Learning strengthens some connections between neurons, known as synapses, and even forms new synapses. These synapses demand a lot of extra energy, though. "That means that at the end of the day, you have a brain that costs you more energy," Dr. Tononi said. "That's where sleep would kick in."

He argues that slow waves weaken synapses through the night. "If everything gets weaker, you still keep your memories, but overall the strength goes down," he said. "The next morning you gain in terms of energy and performance."

Dr. Tononi and his University of Wisconsin colleague, Dr. Chiara Cirelli, present this hypothesis in a paper to be published in the journal Sleep Medicine Reviews. Dr. Tononi believes it can be tested in the future, as scientists document sleep in other animal species. "It would be a very basic thing that would apply to any brain that can change," he said.

It has been almost 600 million years since human ancestors diverged from those of flies. As those ancestors evolved, their sleep evolved as well. Human sleep, for example, features not only slow-wave sleep, but bouts of sleep when the eyes make rapid movements and when we dream. Rapid eye movement, or REM sleep, as it is known, generally comes later in the night, after periods of intense slow-wave sleep.

Other mammals also experience a mix of REM and non-REM sleep, as do birds. Sleep researchers would like to know whether this pattern existed in the common ancestors of birds and mammals, reptilian animals that lived 310 million years ago. It is also possible that birds and mammals independently evolved this sleep pattern, just as birds and bats independently evolved wings.

Answering that question may help scientists understand why REM sleep exists. Scientists have long debated its function, suggesting that it may play important roles in memory or learning. In the Oct. 27 issue of Nature, Jerome Siegel, a sleep expert at the University of California, Los Angeles, argues that REM does not play a vital physiological role like slow-wave sleep. He points out that brain injuries and even medications like antidepressants can drastically reduce REM without any apparent ill effect.

"People who don't have REM sleep are remarkably normal," Dr. Siegel said. "There's no evidence for any intellectual or emotional problems."

So why do mammals and birds have REM sleep at all? "The best answer I can come up with is that it's there to prepare you for waking," Dr. Siegel said. "When the important work of sleep is done, REM sleep just makes you as alert as you can be while you're asleep."

One advantage to being alert but immobile is that you may be better able to escape a predator. Dr. Lima and his colleagues argue in the October issue of Animal Behavior that sleep may have been profoundly shaped during evolution by the constant threat of predators. From this perspective, it is strange that animals would spend hours each day in such a vulnerable state. "It's so stinking dangerous to be shut down like that," Dr. Lima said.

It is possible to imagine an alternative way to let the brain recover: only put small parts of the brain to sleep at a time. But Dr. Lima and his colleagues present a mathematical model suggesting that shutting down the whole brain at once may actually be safer.

"You may be better off just shutting down and sleeping all at once, and do it quickly," Dr. Lima said. "Even though you're fairly vulnerable while you're asleep, your overall vulnerability in a 24-hour period may be lower."

Birds appear to be able to defend against predators with a variation on this strategy. When they feel safe, they sleep with their entire brains shut down, as humans do. But when they sense threats, they keep half their brains awake.

Dr. Lima and his colleagues have demonstrated this strategy in action with several bird species, including ducks. "All we did was put our ducks in a row, quite literally," said Niels Rattenborg, a colleague of Dr. Lima's, now at the Max Planck Institute for Ornithology in Germany. "The ducks on the interior slept more with both eyes closed, and the ducks on the edge slept with one eye open. And they used the eye that was facing away from the other birds."

To give each side of the brain enough rest, the ducks at the ends of the row would stand up from time to time, turn around and sit down again. This allowed them to switch eyes and let the waking half of the brain go to sleep.

The Indiana State team is now studying iguanas to see if they sleep with half their brains, as well. Previous studies have shown that lizards keep one eye closed for long periods of time, but it has not been clear if they have also been half asleep. Monitoring iguana brains with electrodes may give the scientists an answer.

If reptiles and birds turn out to sleep this way, it may be evidence that it is an ancient strategy. It is even possible that the earliest mammals also slept with half a brain. "It's possible that early on in mammal evolution they may have lost it for some reason," Dr. Rattenborg speculated. "It may have conflicted with other functions."

On the other hand, some species of whales and seals sometimes swim with one eye closed while the corresponding hemisphere of the brain produces slow waves. Scientists are still debating whether they are actually asleep in this state. If they are, that suggests that the ancestors of marine mammals reinvented half-brain sleeping. It may have re-emerged as an adaptation to life in the ocean, an environment where predators can come out of nowhere.

While humans and other land mammals may not be able to shut down half the brain, they may be able to cope with predators by adjusting their sleep schedules. Some studies on rats suggest that predators cause the animals to cut back on slow-wave sleep. People often react to stress in the same way.

"Some of the changes we observe in people who are experiencing stress may be some of the same mechanisms in response to predators," Dr. Rattenborg said. "There are no lions sneaking up on them, but the daily stresses of our lives may activate this primordial response."

Dr. Tononi believes that studying animals may ultimately help doctors find more effective ways to treat such sleep disorders. "There are no good guidelines about what is satisfactory sleep, because there is no idea of what it does," he said. "Is seven hours of very light sleep O.K.? Or is deep sleep very important, or REM?"

He added: "It might really be that you can do with less sleep as long as it's doing its job. That's why it's crucial to know what its job is."

Monday, November 07, 2005

mammalian sleep

Clues to the functions of mammalian sleep
Jerome M. Siegel1,Nature 437, 1264-1271 (27 October 2005) doi: 10.1038/nature04285

Top of pageAbstractThe functions of mammalian sleep remain unclear. Most theories suggest a role for non-rapid eye movement (NREM) sleep in energy conservation and in nervous system recuperation. Theories of REM sleep have suggested a role for this state in periodic brain activation during sleep, in localized recuperative processes and in emotional regulation. Across mammals, the amount and nature of sleep are correlated with age, body size and ecological variables, such as whether the animals live in a terrestrial or an aquatic environment, their diet and the safety of their sleeping site. Sleep may be an efficient time for the completion of a number of functions, but variations in sleep expression indicate that these functions may differ across species.

Saying that it is desirable to be well rested and that the body seeks lost sleep with a vigour comparable to or greater than that displayed for food or sex does not answer the question of the functional role of sleep. Why do we spend one-third of our lives asleep? Why has our body evolved to press us relentlessly to make up for lost sleep? Can we separate the drive for sleep, manifested in sleepiness, from the function of sleep, as we can separate hunger from the benefits of food consumption? Why do so many species habitually sleep much more than humans, and others much less, and how do species that sleep for only short periods accomplish the functions of sleep in less time? Why does the daily sleep amount decrease from birth to maturity in all species of terrestrial mammals? And why do we have two kinds of sleep, rapid eye movement (REM) and non-REM (NREM) sleep?

Sleep can be defined as a state of immobility with greatly reduced responsiveness, which can be distinguished from coma or anaesthesia by its rapid reversibility. An additional defining characteristic of sleep is that when it is prevented, the body tries to recover the lost amount. The existence of sleep 'rebound' after deprivation1 demonstrates that sleep is not simply a period of reduced activity or alertness regulated by circadian or ultradian rhythms, a phenomenon that can be seen even in non-sleeping organisms2, 3, 4.

Read the rest here.

Sunday, November 06, 2005

circadiana commentary

(Non) Adaptive Function of Sleep

Here is a nice article in Washington Post - Ecological Niche May Dictate Sleep Habits - about the adaptive function of sleep.

It addresses some of the themes I am interested in.

First, the unfortunate fact is that sleep was initially defined by researchers of humans, i.e., medical researchers. Inevitably, the (electrophysiological) definition of sleep was thus saddled with unneccessary anthropocentric elements that for decades hampered the study of evolution of sleep.

Read the rest here.

Saturday, November 05, 2005

sleep by niche

Ecological Niche May Dictate Sleep Habits
By Shankar Vedantam, Washington Post Staff Writer, Monday, October 31, 2005

For centuries, poets, philosophers and scientists have debated why humans spend as much as a third of their lives asleep.

For Shakespeare, sleep was the "balm of hurt minds" -- denied to murderers such as Macbeth. For Sigmund Freud, sleep provided a platform for dreams, an outlet for the psyche to work out complex and dangerous feelings. Scientists today believe sleep consolidates learning and memory, and supports many essential mental and physical functions.

The theorists have long disagreed about one another's ideas, but most agree on one thing: If nature makes people sleep away so much of their lives, the reason has to be something crucial. That seemed to be the only way to explain why sleep-deprived people crave sleep so badly that they doze off behind the wheel of a car going 60 mph, and why rats deprived of sleep die sooner than rats deprived of food.

Yet a wealth of sleep research has regularly produced baffling paradoxes and conflicting lines of evidence about the uses, role and need for sleep. If sleep is primarily about providing mental rest, why do people's brains remain so active during sleep, as research in recent decades has found?

If sleep is about providing the body with rest, why do couch potatoes need as much sleep as Olympic athletes? Moreover, animals such as horses, which perform far more physical labor than humans, need much less sleep than people do.

If sleep primarily hones cognitive functions, why do the intellectually lazy need as much sleep as Nobel Prize-winning physicists? Also, why do humans -- who are a lot smarter than rats -- sleep less than rodents?

Finally, while much conventional thinking suggests that Americans should be sleeping more, a very large 2002 study found that people who sleep eight hours or more a night are likely to die younger than those who sleep seven. (Don't touch that alarm clock; the study did not find that deliberately sleeping less increases life span.)

Jerome Siegel, a psychiatrist at the University of California at Los Angeles who described these discordant findings in acomprehensive review of the available research, published in the journal Nature last week, said he began to question the notion that sleep performs some essential function after noting that species that sleep less than others do not sleep any deeper -- as they would if they were making up for the shorter time. Animals that sleep fewer hours generally sleep less deeply, while animals that sleep longer usually sleep more deeply.

Siegel, a respected sleep researcher who is also affiliated with the Department of Veterans Affairs, said he came to the conclusion there was only one explanation that could explain the paradoxes: in a word, evolution.

Rather than being designed to perform some critical function, Siegel wrote in his paper, sleep may be the way various species, humans included, have adapted to their ecological niches. While many valuable functions probably take place during sleep, Siegel suggested that it is possible that those functions are not the reason for sleep.

"There is this huge variation in sleep across species, and it fits with this huge variation in the niches that animals occupy," Siegel said in an interview.

"The analogy I make is between hibernation and sleep," he said. "No one says, 'What is hibernation for? It is a great mystery.' . . . It's obvious that animals hibernate because there is no food, and by shutting down the brain and body they save energy."

Sleep, Siegel suggested, may play much the same role. As evidence, he cited research that has found systematic differences in the way carnivores, omnivores and herbivores sleep: Carnivores sleep longer; herbivores, shorter; and omnivores, including humans, are somewhere in the middle.

"If animals have to eat grass all day, they can't sleep a lot, but if they eat meat and are successful at killing an antelope, why bother to stay awake?" he asked.

On the other hand, mammals at greater risk of being eaten -- such as newborns -- spend large amounts of time asleep, presumably safe in hiding places devised by their parents. Supporting the evolutionary explanation, Siegel's own research has shown that when the luxury of safe hiding places is unavailable -- in the ocean, for instance -- baby dolphins and baby killer whales reverse the pattern found among terrestrial mammals. These marine mammals sleep little or never as newborns and gradually increase the amount they sleep as they mature.

The theory does not so much contradict other theories about the role of sleep as much as place them in context: "What I am saying is that it is not that sleep has been adapted to allow some vital function to be fulfilled, but the core function of sleep is to adapt animals to their ecological niche," Siegel said. "Given the animal is inactive for a certain period of the day, certain functions will migrate to that period because it is more efficient" to perform them at that time.

Mark Mahowald, a sleep researcher at the University of Minnesota who wrote about sleep disorders in the same Nature issue, agreed that Siegel's work had shown that "sleep, which likely serves vital functions, serves different functions across the various species."

But Clifford Saper, a neuroscientist at Harvard Medical School and an author of another sleep-related article in last week's Nature, about circadian rhythms, said that despite the variations in sleep across species, "the universality of sleep in all creatures with nervous systems suggests a basic principle that requires explanation."

Saper pointed to the work of his Harvard colleague Robert Stickgold, who published a fourth article in Nature last week describing how memory is consolidated during sleep. Saper said sleep provides brain cells with a period of "down time" that is needed to convert information into learning.

That change, he said, involves biochemical messages being sent from nerve cell projections called dendrites to the nucleus of cells, and that process can take place only when new information is not coming in. The variety of sleeping styles among species, Saper suggested, may be merely linked to their different cognitive needs.

"What a fruit fly learns and what a whale learns and what a human learns may be very different indeed, and so the amount of sleep, and its structure within a day, may be different in each species," he said.

Thursday, October 20, 2005

and a critique of sleep variations

Monday, October 17, 2005

ninety minute sleep cycles

Umm, maybe, maybe not . . .

Check it out here . . . no endorsement from me.

hacking sleep

The post is here with links to additional sites . . .

Friday, August 12, 2005

about listening

here's the lead-in from The Language Log

Rorschach Science

The stimulus? A journal article about fMRI imaging of men listening to variously-hacked men's and women's voices.

The response? Worldwide resonant evocation of sexual stereotypes, congruent and contradictory alike.

Some headlines: "Er, you what, luv?" -- "Man Leaves Wife, Realizes Six Hours Later" -- "Female Voices are Easier to Hear" -- "What We Have is Failure to Communicate" -- "Men do Have Trouble Hearing Women" -- "Why Imaginary Voices are Male" -- "It's official! Listening to women pays off" -- "Men do have trouble hearing women, scientists find".

The blogospheric reactions are just as creative: "I can't hear you,'re just too difficult to listen to" -- "What to tell your wife when you didn't hear her" -- "Men who are accused of never listening by women now have an excuse -- women's voices are more difficult for men to listen to than other men's, a report said" -- "I've been waiting for this for a long time. I'm often accused of 'selective hearing' in which certain statements just disappear from my consciousness - often statements made by Mrs. HolyCoast. It usually occurs when I'm multi-tasking, such as watching TV or blogging while listening to my better half..." -- "Science explains patriarchal monotheism!" ...

So I went and read the journal article: Dilraj S. Sokhi, Michael D. Hunter, Iain D. Wilkinson and Peter W.R. Woodruff, "Male and female voices activate distinct regions in the male brain", In Press, NeuroImage. I'm deeply puzzled by some of the research that paper describes -- if Sokhi et al. really did what they seem to be saying they did, I don't see how the results can be interpreted at all -- but I'm pretty sure that the experiment doesn't mean most of the things that people are saying it does. Maybe none of them.

Read the rest here.

Tuesday, August 09, 2005

about illusions

check out Derren Brown here

about sleep from the New York Times

Explaining Those Vivid Memories of Martian Kidnappers
"Abducted: How People Come to Believe They Were Kidnapped by Aliens,"

by Susan Clancy. Harvard University Press, $22.95.
By BENEDICT CAREY, August 9, 2005, The New York Times

People who have memories of being abducted by aliens become hardened skeptics, of a kind. They dismiss the procession of scientists who explain away the memories as illusions or fantasy. They scoff at talk about hypnosis or the unconscious processing of Hollywood scripts. And they hold their ground amid snickers from a public that thinks that they are daft or psychotic.

They are neither, it turns out, and their experiences should be taken as seriously as any strongly held exotic beliefs, according to Susan Clancy, a Harvard psychologist who interviewed dozens of self-described abductees as part of a series of memory studies over the last several years.

In her book "Abducted," due in October, Dr. Clancy, a psychologist at Harvard, manages to refute and defend these believers, and along the way provide a discussion of current research into memory, emotion and culture that renders abduction stories understandable, if not believable. Although it focuses on abduction memories, the book hints at a larger ambition, to explain the psychology of transformative experiences, whether supposed abductions, conversions or divine visitations.

"Understanding why people believe weird things is important for anyone who wishes to know more about people - that is, humans in general," she writes.

Dr. Clancy's accounting for abduction memories starts with an odd but not uncommon experience called sleep paralysis. While in light dream-rich REM sleep, people will in rare cases wake up for a few moments and find themselves unable to move. Psychologists estimate that about a fifth of people will have that experience at least once, during which some 5 percent will be bathed in terrifying sensations like buzzing, full-body electrical quivers, a feeling of levitation, at times accompanied by hallucinations of intruders.

Some of them must have an explanation as exotic as the surreal nature of the experience itself. Although no one has studied this group systematically, Dr. Clancy suggests based on her interviews, that they tend to be people who already have some interest in the paranormal, mystical arts and the possibility of extraterrestrial visitors. Often enough, their search for meaning lands them in the care of a therapist who uses hypnotism to elicit more details of their dreamlike experiences.

Hypnotism is a state of deep relaxation, when people become highly prone to suggestion, psychologists find. When encouraged under hypnosis to imagine a vivid but entirely concocted incident - like being awakened by loud noises - people are more likely later to claim the scene as a real experience, studies find.

Where, exactly, do the green figures with the wraparound eyes come from? From the deep well of pop culture, Dr. Clancy argues, based on a review of the history of U.F.O. sightings, popular movies and television programs on aliens. The first "abduction" in the United States was dramatized in 1953, in the movie "Invaders From Mars," she writes, and a rash of abduction reports followed this and other works on aliens, including the television series "The Outer Limits."

One such report, by a couple from New Hampshire, Betty and Barney Hill, followed by days a particularly evocative episode of the show in 1961. Mr. Hill's description of the aliens - with big heads and shiny wraparound eyes - was featured in a best-selling book about the experience, and inspired the alien forms in Steven Spielberg's "Close Encounters of the Third Kind" in 1977, according to Dr. Clancy.

Thus does life imitate art, and vice versa, in a narrative hall of mirrors in which scenes and even dialogues are recycled. Although they are distinct in details, abduction narratives are extremely similar in broad outline and often include experimentation with a sexual or procreative subtext. "Oh! And he's opening my shirt, and - he's going to put that thing in my navel," says one 1970's narrative, referring to a needle.

"I can feel them moving that thing around in my stomach, in my body," the narrative, excerpted in the book, continues. The passage echoes other abduction accounts, past and future.

In a laboratory study in 2002, Dr. Clancy and another Harvard psychologist, Richard McNally, gave self-described abductees a standardized word-association test intended to measure proneness to false-memory creation. The participants studied lists of words that were related to one another - "sugar," "candy," "sour," "bitter" - and to another word that was not on the list, in this case, "sweet."

When asked to recall the word lists, those with abduction memories were more likely than a group of peers who had no such memories to falsely recall the unlisted word. The findings suggest a susceptibility to what are called source errors, misattributing sources of remembered information by, say, confusing a scene from a barely remembered movie with a dream.

In another experiment, the researchers found that recalling abduction memories prompted physiological changes in blood pressure and sweat-gland activity that were higher than those seen in post-traumatic stress syndrome. The memories produced intense emotional trauma, and each time that occurs it deepens the certainty that something profound really did happen.

Although no one of those elements - sleep paralysis, interest in the paranormal, hypnotherapy, memory tricks or emotional investment - is necessary or sufficient to create abduction memories, they tend to cluster together in self-described abductees, Dr. Clancy finds. "In the past, researchers have tended to concentrate on one or another" factor, she said in an interview. "I'm saying they all play a role."

Yet abduction narratives often have another, less explicit, dimension that Dr. Clancy suspects may be central to their power. Consider this comment, from a study participant whom Dr. Clancy calls Jan, a middle-age divorcée engaged in a quest for personal understanding: "You know, they do walk among us on earth. They have to transform first into a physical body, which is very painful for them. But they do it out of love. They are here to tell us that we're all interconnected in some way. Everything is."

At a basic level, Dr. Clancy concludes, alien abduction stories give people meaning, a way to comprehend the many odd and dispiriting things that buffet any life, as well as a deep sense that they are not alone in the universe. In this sense, abduction memories are like transcendent religious visions, scary and yet somehow comforting and, at some personal psychological level, true.

Dr. Clancy said she regretted not having asked the abductees she interviewed about religious beliefs, which were not a part of her original research. The reader may regret that, too.

The warmth, awe and emotion of abduction stories and of those who tell them betray strong spiritual currents that will be familiar to millions of people whose internal lives are animated by religious imagery.

When it comes to sounding the depths of alien stories, a scientific inquiry like this one may have to end with an inquiry into religion.

Thursday, July 28, 2005

about this V

This one is right up my meme . . . from Scientific American Mind, with thanks to Clicked

Natural-Born Liars
Why do we lie, and why are we so good at it? Because it works
By David Livingstone Smith, June 2005 Issue

Deception runs like a red thread throughout all of human history. It sustains literature, from Homer's wily Odysseus to the biggest pop novels of today. Go to a movie, and odds are that the plot will revolve around deceit in some shape or form. Perhaps we find such stories so enthralling because lying pervades human life. Lying is a skill that wells up from deep within us, and we use it with abandon. As the great American observer Mark Twain wrote more than a century ago: "Everybody lies ... every day, every hour, awake, asleep, in his dreams, in his joy, in his mourning. If he keeps his tongue still his hands, his feet, his eyes, his attitude will convey deception." Deceit is fundamental to the human condition.

Research supports Twain's conviction. One good example was a study conducted in 2002 by psychologist Robert S. Feldman of the University of Massachusetts Amherst. Feldman secretly videotaped students who were asked to talk with a stranger. He later had the students analyze their tapes and tally the number of lies they had told. A whopping 60 percent admitted to lying at least once during 10 minutes of conversation, and the group averaged 2.9 untruths in that time period. The transgressions ranged from intentional exaggeration to flat-out fibs.

Interestingly, men and women lied with equal frequency; however, Feldman found that women were more likely to lie to make the stranger feel good, whereas men lied most often to make themselves look better.

In another study a decade earlier by David Knox and Caroline Schacht, both now at East Carolina University, 92 percent of college students confessed that they had lied to a current or previous sexual partner, which left the husband-and-wife research team wondering whether the remaining 8 percent were lying. And whereas it has long been known that men are prone to lie about the number of their sexual conquests, recent research shows that women tend to underrepresent their degree of sexual experience. When asked to fill out questionnaires on personal sexual behavior and attitudes, women wired to a dummy polygraph machine reported having had twice as many lovers as those who were not, showing that the women who were not wired were less honest. It's all too ironic that the investigators had to deceive subjects to get them to tell the truth about their lies.

These references are just a few of the many examples of lying that pepper the scientific record.

And yet research on deception is almost always focused on lying in the narrowest sense-literally saying things that aren't true. But our fetish extends far beyond verbal falsification. We lie by omission and through the subtleties of spin. We engage in myriad forms of nonverbal deception, too: we use makeup, hairpieces, cosmetic surgery, clothing and other forms of adornment to disguise our true appearance, and we apply artificial fragrances to misrepresent our body odors.

We cry crocodile tears, fake orgasms and flash phony "have a nice day" smiles. Out-and-out verbal lies are just a small part of the vast tapestry of human deceit.

The obvious question raised by all of this accounting is: Why do we lie so readily? The answer: because it works. The Homo sapiens who are best able to lie have an edge over their counterparts in a relentless struggle for the reproductive success that drives the engine of evolution. As humans, we must fit into a close-knit social system to succeed, yet our primary aim is still to look out for ourselves above all others. Lying helps. And lying to ourselves--a talent built into our brains--helps us accept our fraudulent behavior.

Read the rest here . . .

about this IV

From The University of San Francisco

Psychology Professor Discovers Human Lie Detectors

Psychology Professor Maureen O’Sullivan’s long-term study of people especially good at detecting liars has discovered a new group: emotionally intelligent “geniuses.”

“It’s taken us about 15 years to find these people because there are only about one in a thousand who have these skills,” O’Sullivan said. O’Sullivan and her research partner, Paul Ekman, of the University of California, San Francisco, first began studying facial expressions related to lying in the 1980s. Today their work focuses on the skills of especially acute observers and how they got that way. To qualify as a “genius,” observers have to show at least 80 percent accuracy on O’Sullivan’s lie detecting tests.

Certain groups, such as Secret Service agents or arbitrators used to observing peoples’ reactions to their tactics, score better than average at discerning liars. But after testing more than 12,000 subjects, O’Sullivan has thinned her study group to about 29 super-human lie detectors.“People who are good have to have a devotion (to their talent),” O’Sullivan said. Her group includes artists, therapists, police officers, and a law student and faculty member of the USF School of Law. Some are introverted—the classic observer personality—but others are outgoing. One thing they all have is a drive to observe people and benefit from their observations.

“I had one expert who worked as a waitress and watched people because she wanted to discern who would tip well,” O’Sullivan said. “She was scientific about it. If she was wrong, she would ask herself why.”

O’Sullivan’s work has made her an expert in emotional intelligence. She is often asked to coach federal and local security personnel on detecting lying and she is applying her work to counter-terrorism practices. She is currently writing a mainstream book about her findings.

O’Sullivan tests her subjects by asking them to watch films of people lying or telling the truth and then evaluating what they saw. If the subjects are at least 80 percent correct on three tests, they are added to O’Sullivan’s list of acute observers and asked to undergo additional tests and interviews. She said there is no “Pinocchio nose” that can give away a liar. Odd or inconsistent changes in a person’s verbal or non-verbal behavior, increases in vocal pitch, or changes in hand and body gestures can indicate they’re feeling uncomfortable about what they’re saying, and perhaps lying.“

Although people talk about a ‘gut-reaction’ what they are really doing is paying attention to all kinds of palpable, non-verbal kinds of communication,” she said.

about this III

the facial decoding manual can be found here

about this II

Emotions and Smiling

Next time your boss or your lover gives you a lopsided smile, start worrying, they're probably lying. Can we learn to tell fake emotion from the real thing, asks Rosie Mestel

"How do I know who you are?" demands psychologist Paul Ekman, brandishing my New Scientist business card as we wait for our food in the hole-in-the-wall Chinese restaurant. "You could easily have printed this card up. For all I know you're an agent for the new agency that's taken over from the KGB." I smile back nervously across the table.

On the one hand, I know that he knows I am not a secret agent, though such persons would definitely have a vested interest in milking Ekman for information. An expert in lie-detection, he's been hounded for advice over the years by everyone from the US Secret Service to a sinister-sounding "electrical institute responsible for interrogations" in the former Soviet Union. On the other hand, I have also learned that there's a right way and a wrong way to smile authentically, and that Ekman of all people will know the difference. Have I got it right? Are the muscles round my eyes puckering up in that proper, "real-smile" way? If they aren't, perhaps he thinks I'm hiding something. The need to make my smile genuine blows any chance of making it so.

In fact, Ekman isn't even bothering to decipher my smile, which fits nicely with the point that he's just been trying to make. People, he says, are remarkably trusting in their social interactions. They tend to assume they're being told the truth, and that the expression on someone's face actually reflects the feelings underneath. This despite the fact that lies and emotional fakery abound in daily conversation. What's more, even the most practised of lie-detectors -- police, polygraph operators, psychiatrists and customs inspectors -- do barely better than random chance at discriminating lie from truth, or a feigned from a true emotion.

Ekman thinks it's high time we turned to science. For the past few decades at the University of California, San Francisco, he's been trying to tease out the subtle emotional cues that betray a liar and reveal whether happy, sad and angry faces are felt or false. "I would like to see terrorists caught and assassins stopped," he says, as he sips away at his hot-and-sour soup. "I would like to see the falsely imprisoned ot imprisoned and the actual guilty caught." He'd also like to help psychiatrists work out whether patients asking to go home are really feeling better or just faking it so they can have another go at killing themselves. And besides all that, he simply finds the subject fascinating.

With the information that he's gleaned so far, Ekman reckons he could build a lie-detector with an accuracy of 80 to 90 per cent. Kick out that small group of people that Ekman calls "natural liars" -- people who lie so smoothly and cleanly that they're almost impossible to catch -- and the success rate for the rest could climb close to 100 per cent. It'll never reach the perfect score, though -- people are too much of a behavioural hotchpotch for that, and there is no one behavioural tick that always accompanies a lie. "It's not that I think I have a panacea," Ekman says. "I just have some additional tools that could help."

Ekman's fascination with deception is a natural offshoot from twenty-five years spent studying the face we present to the world, which constantly changes its form as different combinations of the 42 muscles contract and contort our rubbery flesh. Sometimes we are expressing true emotions: our "zygomatic major" muscles, which stretch from each edge of our mouth to our cheekbones, automatically yank tight when we get that wonderful promotion. And up come our lip corners. But often we don't feel the emotions we display at all. What if a particularly loathsome colleague bagged the promotion instead? We'd still find a way to get those zygomatic major muscles working as we made a show of congratulating him, even if we inwardly cursed the injustice of it all.

Of course, everyone knows that some smiles come more easily than others. But science, too, supports the notion that a "voluntary" facial expression is physiologically distinct from an involuntary one. This is the kind we make without thinking when we experience something scary, funny, pleasing or infuriating. Two types of people with damage in different parts of their brains tell us so: one group can no longer smile when asked to, but will spontaneously grin (or glower, or grimace) when the relevant feeling takes hold. The faces of the other group give nothing away whatever they feel. Yet they can summon up the required facial expressions on demand.

Logically this suggests that two distinct brain regions must control voluntary and involuntary facial expressions, and that a different one has been damaged in each group of patients. Normally, both systems send out nerve impulses from the brain to the muscles of our face. And that dual capability is very handy in social discourse. Whether it's time to be happy, or simply to look happy, the relevant muscles do their work.

But they aren't always quite the same muscles--a fact that could be invaluable in catching someone out in a lie. Ekman and his long-time colleague, Wallace Friesen, know this is so because they have perfected the art of reading faces. Their "Facial Action Coding System, or FACS, allows them to objectively tally the movement of all our facial muscles, and distinguish between seven thousand different facial expressions (including 19 different types of smiles). Years of work went into generating FACS: Ekman and Friesen had to learn how to contract their own facial muscles one at a time and then decipher what those movements did to the outward appearance of their faces. Today, a person trained in FACS simply looks at a video of a face and decodes its expression into the combination of muscles being pulled, as well as noting how tightly and how long the various muscles contract.

But long before FACS came along, the French anatomist Duchenne de Boulogne, back in 1862, had noticed one key difference between the "real" happy smile and the "fake" happy smile. Only when a smile is really felt will a certain muscle that wraps around the eyes contract, raising the cheek and crumpling the skin near the eyes into furrows of crows-feet. If the mouth-tugging zygomatic major muscle "obeys the will", Duchenne wrote, this second muscle, the orbicularis oculi, does not do so.

Duchenne's finding was largely overlooked at the time, but in recent years Ekman's team has shown that he was right and have named the smile of pure pleasure in his honour. Duchenne smiles correlate well with peoples' self-reported levels of enjoyment, Ekman has found. Others have shown that such smiles are more frequent in depressed patients' hospital discharge interviews than in their admission interviews, and they tend to happen more frequently as patients get better.

Not only that, but Ekman and Richard Davidson, an emotions researcher at the University of Wisconsin, at Madison, has shown that a Duchenne smile is accompanied by activity in the left frontal cortex in the brain, a region involved in experiencing enjoyment. This activation isn't seen in people using just their zygomatic major to smile.

You'd think such distinctions might be very handy clues to deceit. Yet amazingly, people rarely notice them. Consider this test: Ekman videotaped 47 female student nurses watching two sets of film clips, one filled with disturbing images of skin burns and amputations, the other with delightful nature scenes. The students were told that this was an important test to if they could keep their cool on the job. When questioned by the interviewer, both during and after the film, they were to act as if all of the film clips were pleasant.

Ten nurses dropped out of the test--they couldn't keep up the deception. Those who remained, though, were so good at covering their distress that people watching the videotaped interviews with the nurses did hardly better than chance at sorting out lies from truths. These observers included not only the ubiquitous college undergraduate but people drawn from just the professions you'd expect to be good at spotting lies : customs inspectors, psychiatrists, polygraph operators, police and secret service agents.

In another test, researchers asked travellers at airports to carry suspicious packets of white powder through customs for them (we suggest you check the credentials of any "psychologist" who asks you to do something similar). Customs inspectors couldn't sort out the smugglers from the non-smugglers in interviews. Time and again, researchers have found the same thing: most of us are lousy at picking out liars.

And yet the clues are there, says Ekman. His analysis of the nurses, for instance, revealed many more Duchenne-type smiles during interviews after the nature film than after the disgusting film. Moreover, the nurses exhibited another kind of fake smile -- a "masking" smile. Just as the orbicularis oculi is hard to control, so are certain other muscles around the face -- ones that reveal disgust, sadness, fear or contempt. And here the problem is not prodding a muscle into action, but keeping it still. Watching the dark blood spurt from a freshly amputated limb, the student nurse would instinctively grimace in disgust. She knows that she mustn't, and masks it with a smile. But however hard she tries, she can't stop certain "disgust" muscles (such as one that puckers her nose) from contracting.

Ekman calls these muscles we can't control our "reliable" muscles. They're the ones that will give the well-trained observer a clue to our real feelings. Gladness, disgust, sadness and anger, they each have their reliable muscles, says Ekman. Not that everyone is powerless to control these muscles at will: generally, 10 per cent of the population can perform this feat. Woody Allen, for instance, emphasises his speech with a "sadness" reliable muscle that raises and lowers his brows as he talks. Others can learn if they're willing to devote enough time to the task.

Luckily, there are other clues staring you in the face that can betray a smile as a sham, or a fury as unfelt. Forced smiles are less symmetrical than heartfelt smiles. They stay on the face a little too long, and don't fade quite as smoothly. And sometimes, our true feelings flash fleetingly onto our face before we can suppress them. Ekman has a videotape of "Mary", a suicidal woman, brightly explaining to her psychiatrist that she is ready for a weekend at home. Only when the tape was slowed did he notice a super-quick, "micro-expression" of despair, less than a quarter of a second in length, sandwiched between optimistic smiles. Mary, it transpired, was feeling just as bad as ever, and was planning to kill herself as soon as she got home. If she hadn't decided to come clean at the last minute, the doctors would not have known until too late.

Ekman is by no means suggesting that the muscles of the face hold all the answers to lie-detection. There's a whole host of behavioural clues that he and others have unearthed. People gesticulate less with their hands when they're fibbing. The voice rises in pitch with discomfort. Eyes blink more frequently, pupils dilate. People fiddle more with their face, their hair, their clothes. Not only that, but a number of physiological responses -- such as heart rate, skin conductance, blood pressure and breathing rate -- also change with emotional upset (this is the kind of thing polygraphs measure, after all).

There's evidence from work by Ekman and Robert Levenson, at the University of California at Berkeley, that the precise way in which those items change actually differs depending on the emotion expressed. Anger produces bigger increases in finger temperature and heart rate than does happiness, for instance. One day, might we be able to tell whether someone is frothing with fury or racked with guilt by simply consulting a set of physiological read-outs? Ekman doesn't rule out the possibility.

Of course, it would be much simpler if brain-imaging scientists could stumble upon a part of the brain that lit up every time someone told a whopper (Ekman doesn't see this as likely). None of these other things measure lies per se, only emotional states. Sometimes this is all that is needed. For some lies--such as "I feel fine" when you're just about to jump off Tallahatchie bridge, or "This is a lovely nature film" when it's really a picture of third degree skin burns--a betrayal of despair or revulsion might be very, very telling. But having one's heart rate sky-rocket when asked about possible involvement in a murder might be entirely misleading. A nervous innocent person might look guilty as hell. A cool, unfeeling mass-murderer might pass the test with flying colours. This is, of course, scientists' main criticism of polygraph tests.

Nevertheless, Ekman believes that the signals to deceit he has uncovered so far might bump up the odds of pinning down a liar. For instance, he has found that people can be trained to detect micro-expressions and sort out a Duchenne smile from a fake one. But the key is to look at every measure, not just one or two.

We put great store in the words people say, yet aphasics, who have difficulty understanding speech, seem to be rather better at discriminating lies from truth. That can't be a coincidence.

We trust someone who looks us in the eye, but that is one of the first things that any liar worth his salt will attend to. And then there are the truly ridiculous things that psychological studies have shown we do--such as more readily trusting people with baby-like facial proportions, handsome looks and "innocent-sounding" voices. Traits that people are born with.

Every now and again, Ekman stumbles upon a master lie-detector who is fooled by none of these things, a person who routinely scores perfectly or near-perfectly in tests to spot liars. Ekman is desperate to study these marvels. "My measures are only accurate to 80 or 90 per cent," he says. "But they're doing 100 per cent. What do they know that I haven't yet found? Can I build an expert system based on them?"

With Mark Frank of Rutgers University in New Jersey, Ekman has designed a new lie-detection scenario, one that he feels closely mirrors the kind of situation where, like a murder suspect, you have a real incentive to be believed. A person comes into the testing room and is told that he or she can remove a $50 bill from a wallet and keep it--providing they can convince Ekman that they didn't. Be they guilty or innocent, the punishment for not convincing Ekman is two hours in a small cell accompanied by nasty but harmless loud blasts of white noise. Afterwards Ekman learns whether people really took the money or not, courtesy of a well-hidden video camera.

And from tapes of the interrogations he can begin to work out what made some liars more convincing than others.

Still, there's one big mystery not easily tackled in a lab, one that researchers like Ekman are having fun pondering. And that is: why are most of us so terrible at picking out liars? Why would evolution have left us so easily fooled? Wouldn't it be handy to be able to see through the sweet talk of a suitor who wants only quick gratification before moving on, or the snake-oil salesrep who's only after our money?

Most lies, though, are harmless. They are the little lies that help us get along with people--the ones that from an early age we train our children to perfect. Feigned amusement at Uncle Percy's tiresome jokes. Trumped-up delight at the tartan trouser suit Aunt Millie gave us for Christmas. Nobody scrutinises such lies too closely, so nobody is well versed detecting lies. And anyone who refuses to lie or to collude with such lies is generally considered to be socially inept.

On balance, evolution may have decided that it's more important to get along with people than to always know the truth.

about this I


When Alexander the Greeat visited Corinth, he found Diogenes lying in the sun. The king kindly asked him if there was anything he wanted. The surly philosopher replied, "Yes, stand out of my sun."The courtiers were infuriated and spoke ill of Diogenes, but the king remarked, "If I were not Alexander, I should wish to be Diogenes."
(Plutarch, Lives)

Someone said of Callisthenes, Alexander the Great's historian: "What a fortunate man, a part of Alexander's household, privileged to be present at his feasts."Diognes was not impressed. "Say, rather, how unfortunate a man who can neither dine nor sup except at Alexander's pleasure."
(Diogenes Laertius, Eminent Philosophers)

Alexander saw Diogenes rummaging a heap of human bones and asked him what he was looking for. Diogenes answered: "I am searching for the bones of your father, but I cannot distinguish them form those of his slaves."
(J. Braude, Speaker's and Toastmaster's Handbook)

One day Diogenes was observed begging from a statue. Asked what in the world he was doing, he explained, "I am exercising the art of being rejected."
(H. Margolius, Der Lächelnde Philosoph)

When Diogenes saw a child drinking from his cupped hands, he immediately removed his goblet from his bag and dumped it, further reducing his few worldy possessions. He said, "In the practice of moderation a child has become my master."
(H. Margolius, Der Lächelnde Philosoph)

[Asked of his home country] "I am a citizen of the world."
(Diogenes Laertius, Eminent Philosophers)

about sleep

Deep into Sleep
While researchers probe sleep's functions, sleep itself is becoming a lost art.
by Craig Lambert, Harvard Magazine, July-August 2005

Not long ago, a psychiatrist in private practice telephoned associate professor of psychiatry Robert Stickgold, a cognitive neuroscientist specializing in sleep research. He asked whether Stickgold knew of any reason not to prescribe modafinil, a new wakefulness-promoting drug, to a Harvard undergraduate facing a lot of academic work in exam period.

The question resonated on several levels. Used as an aid to prolonged study, modafinil is tantamount to a “performance-enhancing” drug—one of those controversial, and often illegal, boosters used by some athletes. In contrast to wakefulness-producing stimulants like amphetamines, modafinil (medically indicated for narcolepsy and tiredness secondary to multiple sclerosis and depression) does not seem to impair judgment or produce jitters. “There’s no buzz, no crash, and it’s not clear that the body tries to make up the lost sleep,” reports Stickgold. “That said, all sleeping medications more or less derange your normal sleep patterns. They do not produce normal sleep.” Even so, the U.S. military is sinking millions of dollars into research on modafinil, trying to see if they can keep soldiers awake and on duty—in Iraq, for example—for 80 out of 88 hours: two 40-hour shifts separated by eight hours of sleep.

“No—no reason at all not to,” Stickgold told the psychiatrist. “Not unless you think sleep does something.”

When people make the unlikely claim that they get by on four hours of sleep per night, Stickgold often asks if they worry about what they are losing. “You get a blank look,” he says. “They think that sleep is wasted time.” But sleep is not merely “down time” between episodes of being alive. Within an evolutionary framework, the simple fact that we spend about a third of our lives asleep suggests that sleep is more than a necessary evil. Much transpires while we are asleep, and the question is no longer whether sleep does something, but exactly what it does. Lack of sleep may be related to obesity, diabetes, immune-system dysfunction, and many illnesses, as well as to safety issues such as car accidents and medical errors, plus impaired job performance and productivity in many other activities.

Although the modern era of sleep research started in the 1950s with the discovery of REM (Rapid Eye Movement) sleep, the field remained, well, somnolent until recently. Even 20 years ago, “The dominant paradigm in sleep research was that ‘Sleep cures sleepiness,’” says Stickgold. Since then, researchers have developed a far more complex picture of what happens while we snooze. The annual meetings in sleep medicine, which only this year became a recognized medical specialty, now draw 5,000 participants. Harvard has long been a leader in the area. The Medical School’s Division of Sleep Medicine, founded in 1997 and chaired by Baldino professor of sleep medicine Charles Czeisler, has 61 faculty affiliates. The division aims to foster collaborative research into sleep, sleep disorders, and circadian biology, to educate physicians and the lay public, to influence public policy, and to set new standards of clinical practice, aiming, as its website ( declares, to create “a model program in sleep and circadian biology.”

A Culture of “Sleep Bulimia”

Imagine going on a camping trip without flashlights or lanterns. As the sun sets at the end of the day, daylight gradually gives way to darkness, and once the campfire burns down, you will probably go to sleep. At sunrise, there’s a similar gradient in reverse; from the beginning of time, human beings have been entrained to these cycles of light and dark.

Homo sapiens is not a nocturnal animal; we don’t have good night vision and are not especially effective in darkness. Yet in an instant on the evolutionary time scale, Edison’s invention of the light bulb, and his opening of the first round-the-clock power plant on Pearl Street in Manhattan in 1882, shifted our time-and-light environment in the nocturnal direction. At the snap of a switch, a whole range of nighttime activity opened up, and today we live in a 24-hour world that is always available for work or play. Television and telephones never shut down; the Internet allows you to shop, gamble, work, or flirt at 3 a.m.; businesses stay open ever-longer hours; tens of millions of travelers cross multiple time zones each year, worldwide; and with the growth of global commerce and communication, Wall Street traders may need to rise early or stay up late to keep abreast of developments on Japan’s Nikkei exchange or at the Deutsche Bundesbank.

Consequently most of us now sleep less than people did a century ago, or even 50 years ago. The National Sleep Foundation’s 2005 poll showed adult Americans averaging 6.8 hours of sleep on weeknights—more than an hour less than they need, Czeisler says. Not only how much sleep, but when people sleep has changed. In the United States, six to eight million shift workers toil regularly at night, disrupting sleep patterns in ways that are not necessarily amenable to adaptation. Many people get only five hours per night during the week and then try to catch up by logging nine hours nightly on weekends. “You can make up for acute sleep deprivation,” says David P. White, McGinness professor of sleep medicine and director of the sleep disorders program at Brigham and Women’s Hospital. “But we don’t know what happens when people are chronically sleep-deprived over years.”

“We are living in the middle of history’s greatest experiment in sleep deprivation and we are all a part of that experiment,” says Stickgold. “It’s not inconceivable to me that we will discover that there are major social, economic, and health consequences to that experiment. Sleep deprivation doesn’t have any good side effects.”

All animals sleep. Fish that need to keep swimming to breathe sleep with half their brains while the other half keeps them moving. It is uncertain whether fruit flies actually sleep (“We can’t put electrodes in their brains,” says White), but they seem at least to rest, because for extended periods they do not move. When researchers stopped fruit flies from resting by swatting at them, the flies took even longer rest periods. When lab technicians added caffeine to the water that the flies drank, they stayed active longer—and also rested longer after the drug wore off, evidence that the caffeine had disrupted their resting patterns.

Sleeping well helps keep you alive longer. Among humans, death from all causes is lowest among adults who get seven to eight hours of sleep nightly, and significantly higher among those who sleep less than seven or more than nine hours. (“Those who sleep more than nine hours have something wrong with them that may be causing the heavy sleep, and leads to their demise,” White notes. “It is not the sleep itself that is harmful.”)

Sleep is essential to normal biological function. “The immune system doesn’t work well if we don’t sleep,” says White. “Most think sleep serves some neurological process to maintain homeostasis in the brain.” Rats totally deprived of sleep die in 17 to 20 days: their hair starts falling out, and they become hypermetabolic, burning lots of calories while just standing still.

There once was a fair amount of research on total sleep deprivation, like that which killed the rats. Doctors would keep humans awake for 48, 72, or even 96 hours, and watch their performance deteriorate while their mental states devolved into psychosis. For several reasons, such studies rarely happen any more (“Why study something that doesn’t exist?” asks White) and researchers now concentrate on sleep restriction studies.

In this context, it is important to distinguish between acute and chronic sleep deprivation. Someone who misses an entire night of sleep but then gets adequate sleep on the following three days “will recover most of his or her normal ability to function, ” Czeisler says. “But someone restricted to only five hours of nightly sleep for weeks builds up a cumulative sleep deficit. In the first place, their performance will be as impaired as if they had been up all night. Secondly, it will take two to three weeks of extra nightly sleep before they return to baseline performance. Chronic sleep deprivation’s impact takes much longer to build up, and it also takes much longer to recover.” The body is eager to restore the balance; Harvard undergraduates, a high-achieving, sleep-deprived population, frequently go home for Christmas vacation and pretty much sleep for the first week. Stickgold notes that “When you live on four hours a night, you forget what it’s like to really be awake.”

Sleep researcher Eve van Cauter at the University of Chicago exposed sleep-deprived students (allowed only four hours per night for six nights) to flu vaccine; their immune systems produced only half the normal number of antibodies in response to the viral challenge. Levels of cortisol (a hormone associated with stress) rose, and the sympathetic nervous system became active, raising heart rates and blood pressure. The subjects also showed insulin resistance, a pre-diabetic condition that affects glucose tolerance and produces weight gain. “[When] restricted to four hours [of sleep] a night, within a couple of weeks, you could make an 18-year-old look like a 60-year-old in terms of their ability to metabolize glucose,” Czeisler notes. “The sleep-deprived metabolic syndrome might increase carbohydrate cravings and the craving for junk food.”

Van Cauter also showed that sleep-deprived subjects had reduced levels of leptin, a molecule secreted by fat cells that acts in the brain to inhibit appetite. “During nights of sleep deprivation, you feel that your eating goes wacky,” says Stickgold. “Up at 2 a.m., working on a paper, a steak or pasta is not very attractive. You’ll grab the candy bar instead. It probably has to do with the glucose regulation going off. It could be that a good chunk of our epidemic of obesity is actually an epidemic of sleep deprivation.”

Furthermore, “Many children in our society don’t get adequate amounts of sleep,” Czeisler says. “Contrary to what one might expect, it’s common to see irritability and hyperactivity in sleep-deprived children. Is it really surprising that we treat them with wake-promoting drugs like Ritalin?” Schools and athletic programs press children to stay awake longer, and some children may be chronically sleep-deprived. Czeisler once took his daughter to a swim-team practice that ran from eight to nine o’clock at night, and told the coaches that this was too late an hour for children. “They looked at me like I was from another planet,” he recalls. “They said, ‘This is when we can get the pool.’”

Stickgold compares sleep deprivation to eating disorders. “Twenty years ago, bulimics probably thought they had the best of all worlds,” he says. “They could eat all they wanted and never gain weight. Now we know that they were and are doing major damage to their bodies and suffering major psychological damage. We live in a world of sleep bulimia, where we binge on weekends and purge during the week.”

The Fatigue Tax

Lack of sleep impairs performance on a wide variety of tasks. A single all-nighter can triple reaction time and vastly increase lapses of attention. Sleep researcher David Dinges at the University of Pennsylvania studied such lapses using a “psychomotor vigilance task” on pools of subjects who had slept four, six, or eight hours nightly for two weeks. The researchers measured subjects’ speed of reaction to a computer screen where, at random intervals within a defined 10-minute period, the display would begin counting up in milliseconds from 000 to one second. The task was first, to notice that the count had started, and second, to stop it as quickly as possible by hitting a key. It wasn’t so much that the sleep-deprived subjects were slower, but that they had far more total lapses, letting the entire second go by without responding. Those on four hours a night had more lapses than those sleeping six, who in turn had more lapses than subjects sleeping eight hours per night. “The number of lapses went up and up for the whole two weeks,” says David White, “and they hadn’t plateaued at the end of the two-week study!”

There’s fairly large individual variation in susceptibility to the cognitive effects of sleep deprivation: in one of Charles Czeisler’s studies, somewhere between a quarter and a third of the subjects who stayed awake all night contributed two-thirds of the lapses of attention. “Some are more resistant to the impact of a single night of sleep loss,” he says. “But they all fall apart after two nights without sleep.” In a sleep-deprived state, says White, “Most of us can perform at a fairly low level. And a lot can run around sleep-deprived without it being obvious. But truck drivers, neurosurgeons, nuclear-plant workers—after six or eight hours, they have to put a second crew on and give them a break.” Very few people are really immune to sleep deprivation: in Dinges’s study, only one of 48 subjects had the same performance after two weeks of four hours’ nightly sleep as on day one.

Students often wonder whether to pull an all-nighter before an exam. Will the extra studying time outweigh the exhaustion? Robert Stickgold, who has studied sleep’s role in cognition for the past 10 years, reports that it depends on the exam. “If you are just trying to remember simple facts—listing all the kings of England, say—cramming all night works, ” he explains. “That’s because it’s a different memory system, the declarative memory system. But if you expect to be hit with a question like ‘Relate the French Revolution to the Industrial Revolution,’ where you have to synthesize connections between facts, then missing that night of sleep can be disastrous. Your ability to do critical thinking takes a massive hit—just as with alcohol, you’re knocking out the frontal-cortex functions.

“It’s a version of ‘sleeping on a problem,’” Stickgold continues. “If you can’t recall a phone number, you don’t say, ‘Let me sleep on it.’ But if you can’t decide whether to take a better-paying job located halfway across the country—where you have all the information and just have to weigh it—you say, ‘Let me sleep on it.’ You don’t say, ‘Give me 24 hours.’ We realize that it’s not just time; we understand at a gut level that the brain is doing this integration of information as we sleep, all by itself.”

Not only mental and emotional clarification, but the improvement of motor skills can occur while asleep. “Suppose you are trying to learn a passage in a Chopin piano étude, and you just can’t get it,” says Stickgold. “You walk away and the next day, the first try, you’ve got it perfectly. We see this with musicians, and with gymnasts. There’s something about learning motor-activity patterns, complex movements: they seem to get better by themselves, overnight.”

Stickgold’s colleague Matthew Walker, an instructor in psychiatry, studied a simple motor task: typing the sequence “41324” as rapidly and accurately as possible. After 12 minutes of training, subjects improved their speed by 50 to 60 percent, but then reached a plateau. Those who trained in the morning and came back for another trial the same evening showed no improvement. But those who trained in the evening and returned for a retest the following morning were 15 to 20 percent faster and 30 to 50 percent more accurate. “Twenty percent improvement—what’s that?” asks Stickgold, rhetorically. “Well, it’s taking a four-minute mile down to three minutes and 10 seconds, or raising a five-foot high jump to six feet.”

Bodily Rituals

So sleep is essential, but exactly why we go to sleep remains a mystery. Professor of psychiatry Robert McCarley, based at the VA Boston Healthcare System, has linked sleep to the brain neurochemical adenosine. Adenosine binds with phosphorus to create adenosine triphosphate (ATP), a substance that cells break down to generate energy. McCarley and colleagues inserted microcatheters into cat brains while keeping the cats awake for up to six hours—a long time for a cat. They found that rising adenosine levels in the basal forebrain put the cat to sleep; then, in the sleeping cat, adenosine levels fall again. In both cats and humans, the basal forebrain includes cells important for wakefulness, and adenosine turns these cells off, triggering sleep.

Like cats, when we are awake and active, we burn ATP, which breaks down to adenosine. Over time, adenosine levels build up, causing pressure for sleep. During sleep, many of the body’s cells are less active and hence burn less ATP, so adenosine levels fall again, setting the stage for wakefulness.

A drug like caffeine, however, partially blocks adenosine receptors, so the brain doesn’t perceive the actual adenosine level, and we don’t get tired. In a world that values wakefulness and productivity over rest and recovery, caffeine has become, in dollar amounts, the second-largest commodity (after oil) traded in the world. Some consumers require ever-greater jolts—one 24-ounce Starbucks beverage packs a walloping 1,000-plus milligrams of caffeine. (A commonly used figure for one cup of coffee is 100 milligrams.)

The lab run by Putnam professor of neurology Clifford Saper has done related research, refining the location and functions of the “sleep switch,” a group of nerve cells in the hypothalamus that turns off the brain’s waking systems; conversely, the waking systems can turn off the sleep switch. “When you have a switch where either side can turn off the other, it’s what electrical engineers call a ‘flip-flop,’” Saper explains. “It likes to be in one state or the other. So we fall asleep, or wake up, quite quickly. Otherwise we’d be half asleep or half awake all the time, with only brief periods of being fully awake or asleep. But we’re not—we are either awake or asleep.”

The adenosine cycle at least partly explains the homeostatic drive for sleep—the longer we are awake, the greater our fatigue, and pressure to sleep builds up progressively. But circadian rhythms also profoundly affect sleep and wakefulness. Circadian cycles (from circa, meaning “about,” and dies, a “day”) are internal periodic rhythms that control many things like body temperature, hormone levels, sleep and wakefulness, digestion, and excretion. “The circadian cycles go way back in evolutionary time,” Charles Czeisler says. “They are probably older than sleep.”

Since the 1970s, Czeisler has established himself as one of the world’s leading authorities on circadian cycles and the chronobiology of sleep and wakefulness. He has done groundbreaking work in the sleep laboratory at Brigham and Women’s Hospital, where a special wing on one floor is shielded not only from sunlight, but from all external time cues. There, researchers can do exotic things like simulate the 708-hour lunar day or conditions on the International Space Station, where the sun rises and sets every 90 minutes. (Czeisler leads a sleep and chronobiology team that, under the auspices of NASA, researches human factors involved in space travel.)

Exotic light environments like space challenge human biology, partly because people differ from other mammals, which take short catnaps and rat naps throughout the day and night. In contrast, we have one bout of consolidated (unbroken) sleep, and one of consolidated waking, per day (or, in siesta cultures, two of each). In addition, “There is a very narrow window [in the daily cycle] in which we are able to maintain consolidated sleep,” Czeisler says, “and the window gets narrower and narrower as we get older.”

The origins of humans’ consolidated sleep take us to the beginnings of terrestrial life, since even prokaryotes—one-celled organisms like bacteria, lacking a nucleus—have built-in 24-hour rhythms. It is not surprising that these biological clocks are so universal, as they reflect the entrainment of all living things to the primeval 24-hour cycles of light and darkness created by the rotation of Earth.

“The light and dark cycle is the most powerful synchronizer of the internal circadian clock that keeps us in sync with the 24-hour day,” Czeisler says. As late as 1978, when he published a paper demonstrating this effect, many still believed that “social interaction was the most important factor in synchronizing physiological cycles—that we had evolved beyond light,” he says. “But much of our subsequent research shows that our daily cycles are more like those of cockroaches than we want to believe. We are very sensitive to light.”

Light strongly affects the suprachiasmatic nucleus (SCN), a biological clock in the anterior region of the hypothalamus that directs circadian cycles. All cells have internal clocks—even cells in a tissue culture run on 24-hour cycles. “They all oscillate like violins and cellos, but the SCN is the conductor that synchronizes them all together, ” Czeisler explains.

While the homeostatic pressure to sleep starts growing the moment we awaken, the SCN calls a different tune. Late in the afternoon, its circadian signal for wakefulness kicks in. “The circadian system is set up in a beautiful way to override the homeostatic drive for sleep,” Czeisler says. The circadian pacemaker’s signal continues to increase into the night, offsetting the build-up of homeostatic pressure and allowing us to stay awake well into the evening and so achieve our human pattern of consolidated sleep and wakefulness. (There is often a dip in the late afternoon, when the homeostatic drive has been building for hours but the circadian signal hasn’t yet kicked in; Czeisler calls this “a great time for a nap.”) The evolutionary benefit of consolidated sleep and wakefulness is a subject of speculation; Czeisler says that long bouts of wakefulness may enable us to “take advantage of our greater intellectual capacity by focusing our energy and concentration. Frequent catnaps would interrupt that.”

The circadian pacemaker’s push for wakefulness peaks between about 8 and 10 p.m., which makes it very difficult for someone on a typical schedule to fall asleep then. “The period from two to three hours before one’s regular bedtime, we call a ‘wake maintenance zone,’ ” Czeisler says. But about an hour before bedtime, the pineal gland steps up its secretion of the hormone melatonin, which quiets the output from the SCN and hence paves the way for sleep.

Some years ago, melatonin supplements became popular as a natural sleeping pill, but as Czeisler’s research has proven, light is a more powerful influence on the biological clock than melatonin. Mangelsdorf professor of natural sciences J. Woodland Hastings has shown that even a split-second of light exposure can shift the circadian cycle of a single-celled organism by a full hour. Light interferes with sleep, at least partly because it inhibits melatonin secretion and thus resets the biological clock. For this reason, those seeking a sound sleep should probably keep their bedroom as dark as possible and by all means avoid midnight trips to brightly lit bathrooms or kitchens; blue light, with its shorter wavelength—and its resemblance to the sunlit sky—has the most powerful resetting effect.

Light resets the pacemaker even in the case of some completely blind people, who generally lose circadian entrainment and suffer recurrent insomnia. “The eye has two functions, just as the ear does, with hearing and balance,” says Czeisler. “The eye has vision, and also circadian photoreception.” A subset of about 1,000 photosensitive retinal ganglion cells connects by a direct neural pathway to the SCN; these cells are sometimes active even in those who are blind to light. Exposure to bright light will decrease melatonin levels in some blind persons, and this subset, unlike other blind people, generally do not suffer from insomnia and are biologically entrained to the 24-hour day.

Disastrous Exhaustion

The human species, or much of it, anyway, apparently is trying to become simultaneously nocturnal and diurnal. Society has been squeezing the window for restful sleep ever narrower. (Czeisler likes to quote colleague Thomas Roth of the Henry Ford Sleep Disorders Center in Detroit, on the minimal-sleep end of the spectrum. “The percentage of the population who need less than five hours of sleep per night, rounded to a whole number,” says Roth, “is zero.”)

Czeisler has conducted several studies of medical interns, an institutionally sleep-deprived population who provide a hugely disproportionate fraction of the nation’s healthcare services. Interns work famously long 80- and even 100-hour weeks; every other shift is typically 30 hours in duration. “On this kind of schedule, virtually everyone is impaired,” he says. “Being awake more than 24 hours impairs performance as much as having a blood-alcohol level of 0.1 percent—which is legally drunk.”

In addition to both acute and chronic sleep deprivation, interns sleep and wake in patterns that misalign with circadian cycles—being asked, for example, to perform with full alertness at 4 a.m. A fourth factor is that the human brain is “cold” and essentially impaired during the first half-hour after awakening—even more impaired, says Czeisler, than after 70 hours of sleeplessness. “It’s a colossally bad idea to have an intern woken up by a nurse saying, ‘The patient is doing badly—what shall we do?’ ” he says. “They might order 10 times the appropriate dose of the wrong med.”

The intensity and growing technological advance of medical care only enhance the probability of errors under such conditions. Christopher Landrigan, assistant professor of pediatrics, led a study that compared interns working traditional schedules with those on an alternate schedule of fewer weekly hours and no extended (e.g., 30-hour) shifts in intensive-care units. The doctors on the tiring traditional schedule made 36 percent more serious medical errors, including 57 percent more nonintercepted serious errors, and made 5.6 times as many serious diagnostic errors.

Some Harvard-affiliated teaching hospitals, like Brigham and Women’s, where Czeisler works, are taking the lead in substantially reducing work hours for physicians and surgeons in training. Yet no rules limit the work hours of medical students (including those at Harvard Medical School), and at the national level, little has changed for interns and residents. Not long ago, the Accreditation Council of Graduate Medical Education, faced with the threat of federal regulation, enacted new rules limiting extended shifts to 30 hours (before the new rules, they averaged 32 hours), and capped work weeks at 80 hours (beforehand, the average was 72 hours)—with exceptions allowable up to 90 hours. “The new, self-imposed rules largely serve to reinforce the status quo,” Czeisler says. “They haven’t brought about fundamental change, and haven’t changed the length of a typical extended shift, which is still four times as long as a normal workday. And those marathon shifts occur every other shift, all year, several years in a row during residency training.”

The risks don’t end when the doctors leave work. Research fellow in medicine Laura Barger led another group in a nationwide survey of interns that showed them having more than double the risk of a motor-vehicle crash when driving home after an extended shift. (They aren’t alone: 60 percent of American adults drove while drowsy in the past year.)

The moral of much sleep research is startlingly simple. Your mother was right: You’ll get sick, become fat, and won’t work as well if you don’t get a good night’s sleep. So make time for rest and recovery. Stickgold likes to compare two hypothetical people, one sleeping eight hours, the other four. The latter person is awake 20 hours a day, compared to 16 hours for the first. “But if the person on four hours is just 20 percent less efficient while awake, then in 20 hours of waking he or she will get only 16 hours of work done, so it’s a wash,” he says. “Except that they are living on four hours of sleep a night. They’re not gaining anything, but are losing a huge amount: you’ll see it in their health, their social interactions, their ability to learn and think clearly. And I cannot believe they are not losing at least 20 percent in their efficiency.”

Yet instead of encouraging restorative rest, many of our institutions are heading in the opposite direction. This fall, for example, Harvard will begin keeping Lamont Library open 24 hours a day, in response to student demand, and Harvard Dining Services has for several years offered midnight snacks. “These are the wrong solutions,” says Stickgold. “This is like the Boston Police Department getting tired of drunk drivers killing people and setting up coffee urns outside of bars. At Harvard there is no limit on the amount of work students are assigned; you can take four courses and have three professors say, ‘This is your most important course and it should take the bulk of your time.’ Students are dropping to four hours of sleep a night, and the University sees it has to do something about it. But the way you deal with students overloaded with work is not by having dorms serve snacks at midnight and keeping the library open all night. Instead, you can cut back by one-third the amount of work you assign, and do that in every course without serious detriment.”

Such are the prescriptions of sleep researchers, which differ radically from those of the society and the economy. The findings of the sleep labs filter only slowly into the mainstream, especially in areas like medical internships, where enormous financial pressures favor the status quo. Even at Harvard Medical School, in a four-year curriculum, only one semester hour is devoted to sleep medicine. For a sleep disorder like narcolepsy, the average time between symptom onset and diagnosis is seven years; for sleep apnea, four years. “Physicians aren’t being trained to recognize sleep disorders,” Czeisler says.

When all else fails, there is always the option of common sense. Sleep is quite possibly the most important factor in health, and neither caffeine nor sleeping pills nor adrenaline can substitute for it. “As it looks more and more like some of these processes occur exclusively during sleep and can’t be reproduced while we are awake, the consequences of losing them look more and more terrifying,” says Stickgold. “And that’s the experiment we are all in the middle of, right now.”

Craig A. Lambert ’69, Ph.D. ’78, is deputy editor of this magazine.