By Rob Stein, U.S. health authorities recommended Tuesday that doctors diagnose the risk of developing Alzheimer’s disease before people develop full-blown dementia. The National Institutes of Health and the Alzheimer’s Association made the recommendation, which could at least double the number of Americans receiving a diagnosis of Alzheimer’s and its early phases. It is the first revision of the guidelines for diagnosing the brain disease in 27 years. In addition to updating the criteria for diagnosing full Alz­heimer’s, the health authorities created two new categories of the illness: a “preclinical” phase that occurs before patients show any memory loss or other thinking problems, and “mild cognitive impairment,” in which symptoms are subtle. The recommendations are based on the growing realization that Alzheimer’s is the result of a gradual destruction of brain cells that control memory and other cognitive abilities, a process that begins years before clear-cut dementia becomes apparent. “The new guidelines reflect today’s understanding of how key changes in the brain lead to Alz­heimer’s disease,” Creighton Phelps of the NIH’s National Institute on Aging told reporters during a briefing held Monday before the guidelines were released. The recommendations are aimed at helping patients and their families prepare financially, logistically and emotionally for the disease, which can require years of intensive, expensive care.

Keyword: Alzheimers
Link ID: 15239 - Posted: 04.19.2011

By PAM BELLUCK The other day, Paul Simon was rehearsing a favorite song: his own “Darling Lorraine,” about a love that starts hot but turns very cold. He found himself thinking about a three-note rhythmic pattern near the end, where Lorraine (spoiler alert) gets sick and dies. “The song has that triplet going on underneath that pushes it along, and at a certain point I wanted it to stop because the story suddenly turns very serious,” Mr. Simon said in an interview. “The stopping of sounds and rhythms,” he added, “it’s really important, because, you know, how can I miss you unless you’re gone? If you just keep the thing going like a loop, eventually it loses its power.” An insight like this may seem purely subjective, far removed from anything a scientist could measure. But now some scientists are aiming to do just that, trying to understand and quantify what makes music expressive — what specific aspects make one version of, say, a Beethoven sonata convey more emotion than another. The results are contributing to a greater understanding of how the brain works and of the importance of music in human development, communication and cognition, and even as a potential therapeutic tool. Research is showing, for example, that our brains understand music not only as emotional diversion, but also as a form of motion and activity. The same areas of the brain that activate when we swing a golf club or sign our name also engage when we hear expressive moments in music. Brain regions associated with empathy are activated, too, even for listeners who are not musicians. © 2011 The New York Times Company

Keyword: Hearing; Emotions
Link ID: 15238 - Posted: 04.19.2011

By BENEDICT CAREY The answer is neither. Font size has no effect on memory, even though most people assume that bigger is better. But font style does. New research finds that people retain significantly more material — whether science, history or language — when they study it in a font that is not only unfamiliar but also hard to read. Psychologists have long known that people’s instincts about how well they’ve learned a subject are often way off. The feel of a study session can be a poor reflection of its nutritional value: Concepts that seem perfectly clear become fuzzy at exam time, and those that are hard to grasp somehow click into place when it counts. In recent years, researchers have begun to clarify why this is so, and in some cases how to correct for it. The findings are especially relevant nowadays, experts say. “So much of the learning that we do now is unsupervised, on our own,” said Robert A. Bjork, a psychologist at the University of California, Los Angeles, “that it’s crucial to be able to monitor that learning accurately; that is, to know how well we know what we know, so that we avoid fooling ourselves.” Mistakes in judging what we know — in metacognition, as it’s known — are partly rooted in simple biases. For instance, most people assume when studying that newly learned facts will long be remembered and that further practice won’t make much difference. These beliefs are subconscious and automatic, studies find, even though people know better when they stop to think about it. © 2011 The New York Times Company

Keyword: Learning & Memory
Link ID: 15237 - Posted: 04.19.2011

By ANAHAD O’CONNOR Chronic snoring can be more than a noisy nuisance. Up to three-quarters of nightly snorers also have sleep apnea, which causes breathing interruptions throughout the night. Sleep apnea raises the risk of heart disease, stroke and high blood pressure. Snorers looking for a cure are often told to sleep on their sides, not on their backs, so that the base of the tongue will not collapse into the back of the throat, narrowing the airway and obstructing breathing. But for some snorers, changing sleep position may not make much of a difference. Scientists say there are two types of snorers: those who snore only when they sleep on their backs, and those who do it regardless of their position. After sleep researchers in Israel examined more than 2,000 sleep apnea patients, for example, they found that 54 percent were “positional,” meaning they snored only when asleep on their backs. The rest were “nonpositional.” Other studies have shown that weight plays a major role. In one large study, published in 1997, patients who snored or had breathing abnormalities only while sleeping on their backs were typically thinner, while their nonpositional counterparts usually were heavier. The latter group, wrote the authors, consequently suffered worse sleep and more daytime fatigue. But that study also found that patients who were overweight saw reductions in the severity of their apnea when they lost weight. According to the National Sleep Foundation, in people who are overweight, slimming down is generally the best way to cure sleep apnea and end snoring for good. © 2011 The New York Times Company

Keyword: Sleep
Link ID: 15236 - Posted: 04.19.2011

By KATHERINE BOUTON After reading “The Longevity Project,” I took an unscientific survey of friends and relatives asking them what personality characteristic they thought was most associated with long life. Several said “optimism,” followed by “equanimity,” “happiness,” “a good marriage,” “the ability to handle stress.” One offered, jokingly, “good table manners.” In fact, “good table manners” is closest to the correct answer. Cheerfulness, optimism, extroversion and sociability may make life more enjoyable, but they won’t necessarily extend it, Howard S. Friedman and Leslie R. Martin found in a study that covered eight decades. The key traits are prudence and persistence. “The findings clearly revealed that the best childhood personality predictor of longevity was conscientiousness,” they write, “the qualities of a prudent, persistent, well-organized person, like a scientist-professor — somewhat obsessive and not at all carefree.” “Howard, that sounds like you!” Dr. Friedman’s graduate students joked when they saw the statistical findings. On a recent visit to New York, Dr. Friedman and Dr. Martin did both seem statistically inclined to longevity. Conscientiousness abounded. They had persisted in a 20-year study — following up on documentation that had been collected over the previous 60 years by Lewis Terman and his successors — despite scoffing from students: Get a life! The hotel room (Dr. Martin’s) was meticulously neat, and they had prudently ordered tea and fruit from room service. Both were trim and tanned, measured in their answers, trading off responses like the longtime collaborators they are. Despite a busy schedule they were organized enough for a relaxed talk. © 2011 The New York Times Company

Keyword: Stress; Neuroimmunology
Link ID: 15235 - Posted: 04.19.2011

Ewen Callaway "The sight of a feather in a peacock's tail," Charles Darwin wrote in 1860, "makes me sick." The seemingly useless, even cumbersome, gaudy plumage did not fit with his theory of natural selection, in which traits that help to secure survival are passed on. But Darwin eventually made peace with the peacock's train, and its plumage has become the poster child for his theory of sexual selection, in which ostensibly useless traits can evolve when they are preferred by choosy females. In recent years, however, a furious debate has emerged among behavioural ecologists over whether the train of the male peafowl, Pavo cristatus, still woos peahens. Research in which peacocks' tails were experimentally plucked, published online this month in Animal Behaviour1, now suggests that the answer is yes — but only sometimes. "There are other things that we think are going into that decision," says Roslyn Dakin, a PhD student in behavioural ecology at Queen's University in Kingston, Canada. Dakin and a colleague, Robert Montgomerie, tracked three populations of feral peacocks and peahens during the spring breeding season, when hopeful males stage elaborately choreographed routines for picky females. They found that males with very few eyespots in their tail feathers — a measure of the size of the tail — were unattractive to females, but males with more spots than average had no advantage. © 2011 Nature Publishing Group

Keyword: Sexual Behavior; Evolution
Link ID: 15234 - Posted: 04.19.2011

By RONI CARYN RABIN Older people suffering from mild memory and cognition problems may be less likely to progress to full-blown Alzheimer’s disease if they receive treatment for medical conditions like diabetes, high blood pressure and cholesterol, a new study has found. In 2004, researchers at Daping Hospital in Chongqing, China, began following 837 residents ages 55 and older who had mild cognitive impairment but not dementia. Of these, 414 had at least one medical condition that can damage blood vessels and impair blood flow to the brain. After five years, 298 of the study participants had developed Alzheimer’s. Subjects who had had high blood pressure or other vascular problems at the beginning of the study were twice as likely to develop the dementia, compared with those without these risks, the researchers found. Half of those with vascular risks progressed to Alzheimer’s, compared with only 36 percent of those without. Among those participants with vascular problems, those who received treatment were almost 40 percent less likely to develop Alzheimer’s than those who did not, the study also reported. The researchers suggested that vascular risk factors may affect the metabolism of beta-amyloid plaque, which accumulates in the brains of Alzheimer’s patients and seems to play a pivotal role in the disease. © 2011 The New York Times Company

Keyword: Alzheimers
Link ID: 15233 - Posted: 04.18.2011

By NICHOLAS WADE A researcher analyzing the sounds in languages spoken around the world has detected an ancient signal that points to southern Africa as the place where modern human language originated. The finding fits well with the evidence from fossil skulls and DNA that modern humans originated in Africa. It also implies, though does not prove, that modern language originated only once, an issue of considerable controversy among linguists. The detection of such an ancient signal in language is surprising. Because words change so rapidly, many linguists think that languages cannot be traced very far back in time. The oldest language tree so far reconstructed, that of the Indo-European family, which includes English, goes back 9,000 years at most. Quentin D. Atkinson, a biologist at the University of Auckland in New Zealand, has shattered this time barrier, if his claim is correct, by looking not at words but at phonemes — the consonants, vowels and tones that are the simplest elements of language. Dr. Atkinson, an expert at applying mathematical methods to linguistics, has found a simple but striking pattern in some 500 languages spoken throughout the world: A language area uses fewer phonemes the farther that early humans had to travel from Africa to reach it. Some of the click-using languages of Africa have more than 100 phonemes, whereas Hawaiian, toward the far end of the human migration route out of Africa, has only 13. English has about 45 phonemes. © 2011 The New York Times Company

Keyword: Language; Evolution
Link ID: 15232 - Posted: 04.18.2011

By RANDOLPH E. SCHMID WASHINGTON — Reports of sleeping air traffic controllers highlight a long-known and often ignored hazard: Workers on night shifts can have trouble concentrating and even staying awake. "Government officials haven't recognized that people routinely fall asleep at night when they're doing shift work," said Dr. Charles Czeisler, chief of sleep medicine at Brigham and Women's Hospital in Boston. Czeisler said studies show that 30 percent to 50 percent of night-shift workers report falling asleep at least once a week while on the job. So the notion that this has happened only a few times among the thousands of controllers "is preposterous," he said in a telephone interview. In a sign of growing awareness of the problem, the Federal Aviation Administration said Saturday it was changing air traffic controllers' work schedules most likely to cause fatigue. The announcement comes after the agency disclosed another incident in which a controller fell asleep while on duty early Saturday morning at a busy Miami regional facility. According to a preliminary review, there was no impact to flight operations, the FAA said. Czeisler said the potential danger isn't limited to air traffic controllers, but can apply to truck and bus drivers, airline pilots and those in the maritime industry. Who else? Factory workers, police, firefighters, emergency workers, nurses and doctors, cooks, hotel employees, people in the media and others on night or changing shifts. Copyright 2011 The Associated Press.

Keyword: Biological Rhythms; Sleep
Link ID: 15231 - Posted: 04.18.2011

by Jessica Hamzelou THE first clear evidence of how antidepressant drugs help to boost brain cell formation could lead to better treatments for depression. The hippocampus is one of just two brain regions known to grow new neurons throughout life - a process called neurogenesis. This process is disrupted in people with depression, although it is not known whether this is a cause or symptom of the condition. It is clear, however, that one of the ways that antidepressants work is by boosting neurogenesis in the hippocampus. Christoph Anacker and his colleagues at King's College London have now worked out how they do so. Previous research has shown a link between some antidepressants and stress hormones called glucocorticoids. So Anacker's team decided to test whether the antidepressant sertraline acts on the glucocorticoid receptors of brain cells. They grew human hippocampal progenitor cells in a dish and added sertraline. Ten days later, the cultures showed a 25 per cent greater than expected increase in the number of new neurons. When the researchers added a drug to block the glucocorticoid receptors before adding the antidepressant, the number of new neurons produced after 10 days was similar to that expected from natural growth. This suggests that the antidepressant does indeed exert its effect through this receptor (Molecular Psychiatry, DOI: 10.1038/mp.2011.26). © Copyright Reed Business Information Ltd.

Keyword: Depression; Neurogenesis
Link ID: 15230 - Posted: 04.18.2011

by Eliza Strickland Neurobiologist Aniruddh Patel says he often gets e-mail from people who claim that their cats, horses, or other nonfeathered pets have rhythm. Patel suspects that these cases are akin to the dancing dogs featured in YouTube videos, in which the animals don’t innately respond to the beat but instead react to cues from their human partners. However, if your pet really does have rhythm, he wants to know about it. “If someone has a dog that can dance to the beat, it will totally refute my hypothesis,” he says, “and that’s progress in science.” So you think you can dance? You probably can, thanks to a brain that is remarkably adept at perceiving rhythms and synchronizing our body movements to what we hear. The ability to get into the groove—to step to the beat—is a hallmark of our species, raising the question of why we might have evolved this ability. Neurobiologist Aniruddh Patel at the Neurosciences Institute in San Diego looks for answers in brain scans and 
laboratory tests and also in the fancy footwork of what seems to be another dance-loving species, the sulfur-crested cockatoo. By monitoring the brain regions that activate when people hear a beat, Patel and colleague John Iversen find evidence that our hearing system is entwined with the motor control systems that guide our muscles. Patel proposes that these connections are a happy accident of evolution, a by-product of the brain development that allowed humans to learn to speak. We take our ability to groove for granted, but it turns out that scientific studies show it’s quite rare. How many other animals can rock out?
 It’s a behavior that seems so simple at first glance: How complicated can it be to bob up and down to music? You can do it while you’re drunk. And yet almost no other species can. In 2009 a team of Mexican researchers conducted a study with monkeys, trying to train the animals to tap to the beat of a metronome. Even after a year or two of training, the monkeys couldn’t do it. The results surprised people, because these monkeys are routinely taught really complicated things, and following a rhythm seems as if it should be easy. © 2011, Kalmbach Publishing Co.

Keyword: Evolution
Link ID: 15229 - Posted: 04.18.2011

By Rob Stein, CHATOM, Ala. — When Timothy J. Atchison regained consciousness, he was drenched in blood and pinned in his car on the side of a dark rural road. “I was just pouring blood,” said Atchison, 21, who said he recoiled in pain when he tried to drag himself through a window of the wrecked Pontiac, a high-school graduation gift. “I didn’t know if I was going to bleed to death or not.” Then, Atchison said, he realized that his legs felt strangely huge — and completely numb. He was paralyzed from the chest down. “I was just praying — asking for forgiveness and thanking God for keeping me alive,” said Atchison, who was trapped for at least an hour before rescuers freed him. “I said, ‘From here on out, I’m going to live for you and nothing else.’ I never got down after that. I figure that’s what must have kept me up — God keeping me up.” That sense of destiny propelled Atchison when he faced another shock just seven days later: Doctors asked him to volunteer to be the first person to have an experimental drug made from human embryonic stem cells injected into his body. “We were just stunned,” said Atchison, who was with his mother and grandfather when researchers approached him. “We were like, ‘Whoa, really?’ We were all just kind of in awe.” Atchison, known to friends and family as T.J., described the events during an interview Tuesday with The Washington Post — his first detailed account since disclosing his carefully guarded identity to The Post. Atchison’s story reveals provocative insights into one of the most closely watched medical experiments, including what some might see as irony: that a treatment condemned on moral and religious grounds is viewed by the first person to pioneer the therapy, and by his family, as part of God’s plan.

Keyword: Stem Cells; Regeneration
Link ID: 15228 - Posted: 04.16.2011

By Jeremy Laurance One of life's disappointments is the recognition that we have not realised our potential; the realisation that had we tried harder, worked longer, played less, we might have achieved more. It is the foundation of the mid-life crisis. Parents say to their children preparing for an exam: "Just do your best." It is supposed to be encouraging – but is it? It is not easy to do your best. Indeed, it may be impossible. This becomes all too clear as we move into adulthood. The fiercest competition of our lives is the one we have with ourselves. There is much more involved than the small matter of will power. So could we be helped to do our best? The movie Limitless, released recently, deals directly with this conundrum. Its hero, Eddie Morra (Bradley Cooper), is an unkempt, unaccomplished writer who finds a way of bridging the gap between the nobody he is and the somebody he aspires to be – with the drug NZT, rocket fuel for the brain – a cognitive enhancer that turbo-charges memory, cranks up concentration and eliminates fatigue. After swallowing a dose, Eddie completes a hefty chunk of his book in an afternoon, learns the piano in three days, picks up Italian from a Berlitz tape and wins a street fight using moves remembered from Bruce Lee flicks. Women suddenly find him irresistible. So far so good. But NZT has a downside. Soon Eddie is double-dosing, running out of supplies and desperate for more. The movie ends in a confusion of plot twists that has left critics floundering. The strength of Limitless is the credibility of its central idea. It is not so far- fetched to imagine that "smart drugs" like NZT might one day exist. Versions of them already do – and their use is growing. The key chemical substances in this field are Ritalin, an amphetamine substitute, and its stronger relative Adderall. They are prescribed to children with attention deficit disorder but are increasingly illicitly obtained and used to boost concentration. ©independent.co.uk

Keyword: ADHD; Drug Abuse
Link ID: 15227 - Posted: 04.16.2011

By Melissa Dahl There's a reason certain episodes of "The Office" or "Curb Your Enthusiasm" -- or those painful audition episodes of "American Idol" -- make you so uncomfortable. A team of European scientists has uncovered a neural explanation for vicarious embarrassment, that cringe-inducing phenomenon of feeling embarrassed for someone. Whether Michael Scott, the boss of the fictional paper company in "The Office" (or -- even worse -- his British counterpart David Brent), realizes he's humiliating himself or not, observing his awkward moments activates the region of our brains that processes empathy. That's what's making us squirm, according to the study, published this week in the journal PLoS ONE. In one experiment, the researchers used functional magnetic resonance imaging to examine the brain's "pain matrix" -- the anterior cingulate cortex and the anterior insula -- while the 619 participants read a series of vignettes describing embarrassing moments. (Yes, that "pain matrix" is the area that processes actual, physical pain, but previous research has shown that this is where social pain, including empathy, is felt, too.) Protagonists in the vignettes slipped in mud, walked around with their fly open, burped loudly in a fancy restaurant and wore T-shirts bragging about their sexual prowess. In other words, some realized they were being ridiculous, while others did not. "Vicarious embarrassment was experienced regardless of whether the observed protagonist acted accidentally or intentionally and was aware or unaware that he/she was in an embarrassing situation," write the study authors, led by Sören Krach and Frieder M. Paulus from Philipps-University Marburg, Germany. © 2011 msnbc.com

Keyword: Emotions; Pain & Touch
Link ID: 15226 - Posted: 04.16.2011

Teen drivers who start school earlier in the morning may be prone to more automobile accidents, according to a new U.S. study. Students may not be so alert, the study suggests, since early school start times may promote sleep loss and daytime sleepiness. Published in the Journal of Clinical Sleep Medicine, the study's lead author, Dr. Robert Vorona, said that starting high school later in the morning might make young drivers more alert because they get more sleep. P.O.V. Do you think classes for high school students should start later so teens can get more sleep? The study compared school start times and automobile crash rates for students aged 16 to 18 years in Virginia Beach, Va., where high school classes began between 7:20 a.m. and 7:25 a.m., to students at schools in adjacent Chesapeake, Va., where classes started between 8:40 a.m. and 8:45 a.m. There were 65.8 automobile crashes for every 1,000 teen drivers in Virginia Beach, and 46.6 crashes for every 1,000 teen drivers in Chesapeake. The comparisons were made in 2008 and were similar to results in 2007. "We believe that high schools should take a close look at having later start times to align with circadian rhythms in teens and to allow for longer sleep times," said Vorona who is an associate professor of internal medicine at Eastern Virginia Medical School. "Too many teens in this country obtain insufficient sleep. Increasingly, the literature suggests that this may lead to problematic consequences including mood disorders, academic difficulties and behavioral issues." © CBC 2011

Keyword: Sleep; Development of the Brain
Link ID: 15225 - Posted: 04.16.2011

By Leon Neyfakh On a recent Monday afternoon, the distinguished Harvard biologist Edward O. Wilson was at his home in Lexington, talking on the phone about the knocks he’s been taking lately from the scientific community, and paraphrasing Arthur Schopenhauer to explain his current standing in his field. “All new ideas go through three phases,” Wilson said, with some happy mischief in his voice. “They’re first ridiculed or ignored. Then they meet outrage. Then they are said to have been obvious all along.” Wilson is 81, an age at which he could be forgiven for retreating to a farm and lending his name to the occasional popular book about science. Over the past year he’s tried his hand at fiction writing, publishing a novel about ants — his scientific specialty — and landing a short story in The New Yorker. But he has also been pressing a disruptive scientific idea, one he reckons is currently in phase two of the Schopenhauer progression: outrage. What Wilson is trying to do, late in his influential career, is nothing less than overturn a central plank of established evolutionary theory: the origins of altruism. His position is provoking ferocious criticism from other scientists. Last month, the leading scientific journal Nature published five strongly worded letters saying, more or less, that Wilson has misunderstood the theory of evolution and generally doesn’t know what he’s talking about. One of these carried the signatures of an eye-popping 137 scientists, including two of Wilson’s colleagues at Harvard. © 2011 NY Times Co.

Keyword: Emotions; Evolution
Link ID: 15224 - Posted: 04.16.2011

Hayley Crawford, reporter The world's first computerised map of the brain was released yesterday by scientists at the Allen Institute for Brain Science, in Seattle, Washington, after more than four years of cutting-edge research. The Human Brain Atlas is an interactive research tool that will help scientists to understand how the brain works and aid new discoveries in disease and treatments. The information used to build it comes from the analysis of two human brains, using magnetic resonance imaging (MRI) and a variation of MRI called diffusion tensor imaging. Allan Jones, the CEO of the institute, told Wired how the brains were also chopped up into small pieces, and RNA extracted from the tissue. They used this RNA to obtain a read-out of the 25,000 genes in the human genome. All this information was put together to create a detailed map of the brain. One thousand anatomical sites in the brain can be searched, supported by more than 100 million data points that indicate the gene expression and biochemistry of each site. For example, a researcher could quickly create a 3D snapshot (see image below) of all the locations in the brain where Prozac's biochemical targets are expressed. Prozac-target.jpg © Copyright Reed Business Information Ltd.

Keyword: Miscellaneous
Link ID: 15223 - Posted: 04.16.2011

By BRYSON VOIRIN On Isla Iguana the sun rises over the Pacific Ocean and sets, somewhat counterintuitively, over the mainland. Pausing briefly to soak in the mysterious and picturesque sunset, we gear up for a long night of bird catching. Tonight we’re hoping to outfit our first frigate bird with the newly developed sleep logger, accelerometer and GPS unit. We’ll record two-paired electroencephalograms (EEGs), constant acceleration in three directions and a GPS position every five minutes. If all goes according to plan the loggers will record for five days. The data from the loggers should help us answer the question of whether sleeping on the wing is possible for frigate birds. A close-up of a neurologger, developed by Alexei Vyssotski. The logger is completely exposed to the elements, so before each use we have to throughly waterproof it.Bryson Voirin A close-up of a neurologger, developed by Alexei Vyssotski. The logger is completely exposed to the elements, so before each use we have to thoroughly waterproof it. Before heading into the field we have to prepare the sleep logger for deployment. The loggers were recently developed by our colleague Alexei Vyssotski in Switzerland, and can record brainwaves and constant acceleration on almost any animal. But preparing them for use in the wild requires a bit of soldering and ingenuity. To minimize the amount of weight for the birds, my adviser, Niels Rattenborg, brought tiny zinc air batteries designed for hearing aids that should power the logger for five days. However, zinc air batteries require an air supply to function. When I put these loggers on the sloths, I used a lithium robotics battery that can be tightly wrapped and waterproofed. But for these new batteries, we have to allow them room to “breathe.” That wouldn’t be an issue in a laboratory, but frigate birds fly around catching fish in saltwater. © 2011 The New York Times Company

Keyword: Sleep; Evolution
Link ID: 15222 - Posted: 04.16.2011

By MAGGIE JONES We all know that we don’t get enough sleep. But how much sleep do we really need? Until about 15 years ago, one common theory was that if you slept at least four or five hours a night, your cognitive performance remained intact; your body simply adapted to less sleep. But that idea was based on studies in which researchers sent sleepy subjects home during the day — where they may have sneaked in naps and downed coffee. Enter David Dinges, the head of the Sleep and Chronobiology Laboratory at the Hospital at University of Pennsylvania, who has the distinction of depriving more people of sleep than perhaps anyone in the world. In what was the longest sleep-restriction study of its kind, Dinges and his lead author, Hans Van Dongen, assigned dozens of subjects to three different groups for their 2003 study: some slept four hours, others six hours and others, for the lucky control group, eight hours — for two weeks in the lab. Every two hours during the day, the researchers tested the subjects’ ability to sustain attention with what’s known as the psychomotor vigilance task, or P.V.T., considered a gold standard of sleepiness measures. During the P.V.T., the men and women sat in front of computer screens for 10-minute periods, pressing the space bar as soon as they saw a flash of numbers at random intervals. Even a half-second response delay suggests a lapse into sleepiness, known as a microsleep. The P.V.T. is tedious but simple if you’ve been sleeping well. It measures the sustained attention that is vital for pilots, truck drivers, astronauts. Attention is also key for focusing during long meetings; for reading a paragraph just once, instead of five times; for driving a car. It takes the equivalent of only a two-second lapse for a driver to veer into oncoming traffic. © 2011 The New York Times Company

Keyword: Sleep
Link ID: 15221 - Posted: 04.16.2011

By Bruce Bower MINNEAPOLIS — Orangutans swim about as well as they fly, but research on three Indonesian islands shows that these long-limbed apes nonetheless catch and eat fish. Orangutans living in Borneo scavenge fish that wash up along the shore and scoop catfish out of small ponds for fresh meals, anthropologist Anne Russon of York University in Toronto reported on April 14 at a meeting of the American Association of Physical Anthropologists. Over two years, Russon saw several animals on these forested islands learn on their own to jab at catfish with sticks, so that the panicked prey would flop out of ponds and into a red ape’s waiting hands. “If orangutans can do this, then early hominids could also have practiced tool-assisted fishing,” Russon said. Although orangutans usually fished alone, Russon observed pairs of apes catching catfish on a few occasions. In one case, an orangutan cringed and pulled away as its companion extracted a fish from a pond. Russon suspects that the onlooker was learning — or at least trying to learn — how to nab aquatic snacks. Observations of fishing by orangutans raise the likelihood that hominids ate meat, including fish, before the emergence of the Homo genus around 2.5 million years ago (SN: 9/11/10, p. 8), said anthropologist David Braun of the University of Cape Town in South Africa. Anthropologists have traditionally held that meat-eating first assumed prominence among early Homo species and fueled brain expansion. © Society for Science & the Public 2000 - 2011

Keyword: Evolution
Link ID: 15220 - Posted: 04.16.2011