by Andy Coghlan A STRANGE property marks out the brain cells of people with Alzheimer's: they have a glut of cells with more than the standard two sets of chromosomes. Furthermore, these turn out to be the cells most likely to perish in the late stages of the disease. The twin discoveries could drive research into one of the modern world's most devastating neurological conditions in an entirely new direction. No one can agree on the cause of Alzheimer's disease. While much of the focus has been on the plaques that clog up the brains of sufferers, treatments that clear these plaques have no effect on the symptoms of the disease. And treatments that block the beta-amyloid proteins that make up the plaques, or the tau proteins that develop within neurons. Perhaps that's because the disease is triggered by something completely different. Last year, Thomas Arendt's team at the University of Leipzig in Germany examined tissue taken from healthy brains and from the brains of those who had Alzheimer's at the time of death, or who showed signs of being about to develop the disease. They found that about 10 per cent of neurons in the brains of healthy people contained more than two sets of chromosomes, a condition known as hyperploidy. The finding is astonishing because all cells in the human body - other than sperm and eggs - are supposed to contain just two sets of chromosomes. More importantly, in the period just before Alzheimer's develops and in the early stages of the disease, Arendt and colleagues found that hyperploid cells double in number. Then, in the final stage of Alzheimer's, most of these unusual cells disappear altogether - of the brain cells lost, 90 per cent are hyperploid (see diagram) (American Journal of Pathology, DOI: 10.2353/ajpath.2010.090955). © Copyright Reed Business Information Ltd.

Keyword: Alzheimers; Genes & Behavior
Link ID: 15319 - Posted: 05.12.2011

by Elizabeth Norton Lasley The waters of the North Sea are among the murkiest on the planet, so dark and silty that a seal sometimes can’t see its own whiskers. Even so, the harbor seals there can hunt and catch fish. Marine biologists have known for several years that a seal relies on its whiskers to follow the wake a fish leaves behind. But according to a new study, whiskers supply detailed information that the seal may use to decide which fish are most worthwhile to hunt. To find out just what a seal’s whiskers can tell it, biologist Wolf Hanke of the University of Rostock in Germany and colleagues enlisted the aid of a harbor seal named Henry, a veteran research participant who has been at the University of Rostock’s Marine Science Center since 2008. “When he starts working, he can’t be stopped,” Hanke says. The researchers presented Henry with different types of wakes using a test box of still water about 2 meters wide that sat at the bottom of a pool about 1 meter deep. Above the box hung a motorized arm with a series of paddles of different shapes and widths. While each paddle moved through the water, Henry waited outside the test box wearing headphones to block out the motor noise. He also wore a blindfold to ensure that he’d be using only his whiskers. Once the paddle had come to rest, Henry left his station and dunked his body halfway into the test box. With the water swirling around his whiskers, Henry made his decision, then left the box and pressed one of two buttons with his nose, indicating whether the wake had been made by one of three paddle sizes he’d already been trained to recognize or by an unfamiliar one. © 2010 American Association for the Advancement of Science.

Keyword: Pain & Touch
Link ID: 15318 - Posted: 05.12.2011

by Kayt Sukel Our intrepid reporter performs an intimate act in an fMRI scanner to explore the pathways of pleasure and pain WITH a click and a whirr, I am pulled into the scanner. My head is strapped down and I have been draped with a blanket so that I may touch my nether regions - my clitoris in particular - with a certain degree of modesty. I am here neither for a medical procedure nor an adult movie. Rather, I am about to stimulate myself to orgasm while an fMRI scanner tracks the blood flow in my brain. My actions are helping Barry Komisaruk at Rutgers University in Newark, New Jersey, and colleagues to tease apart the mechanisms underlying sexual arousal. In doing so, not only have they discovered that there is more than one route to orgasm, but they may also have revealed a novel type of consciousness - an understanding of which could lead to new treatments for pain (see Top-down pain relief). Despite orgasm being a near-universal human phenomenon, we still don't know all that much about it. "The amount of speculation versus actual data on both the function and value of orgasm is remarkable," says Julia Heiman, director of the Kinsey Institute for Research in Sex, Gender and Reproduction in Bloomington, Indiana. It is estimated that one in four women in the US has had difficulty achieving orgasm in the past year, while between 5 and 10 per cent of women are anorgasmic - unable to achieve orgasm at all. But without precise data to explain what happens during this experience, there are few treatment options available for women who might want help. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Attention
Link ID: 15317 - Posted: 05.12.2011

Ewen Callaway The first humans to reach Europe may have found it a ghost world. Carbon-dated Neanderthal remains from the foothills of the Caucasus Mountains suggest that the archaic species had died out before modern humans arrived. The remains are almost 10,000 years older than expected. They come from just one cave in western Russia, called Mezmaiskaya, but bones at other Neanderthal sites farther west could also turn out to be more ancient than previously thought, thanks to a precise carbon-dating technique, says Thomas Higham, a palaeoanthropologist at the University of Oxford, UK, and a co-author of a study published this week in the Proceedings of the National Academy of Sciences1. The implication, says Higham's team, is that Neanderthals and humans might never have met in Europe. However, the Neanderthal genome, decoded last year2, hints that the ancestors of all humans, except those from Africa, interbred with Neanderthals somewhere. Perhaps humans departing Africa encountered resident Neanderthals in the Middle East. "DNA results show that there was admixture probably at some stage in our human ancestry, but it more than likely happened quite a long time before humans arrived in Europe," says Ron Pinhasi, an archaeologist at University College Cork in Ireland, who is lead author of the latest study. "I don't believe there were regions where Neanderthals were living next to modern humans. I just don't find it very feasible," he adds. © 2011 Nature Publishing Group,

Keyword: Evolution
Link ID: 15316 - Posted: 05.10.2011

By GARDINER HARRIS Nearly one in seven elderly nursing home residents, nearly all of them with dementia, are given powerful atypical antipsychotic drugs even though the medicines increase the risks of death and are not approved for such treatments, a government audit found. More than half of the antipsychotics paid for by the federal Medicare program in the first half of 2007 were “erroneous,” the audit found, costing the program $116 million for those six months. “Government, taxpayers, nursing home residents as well as their families and caregivers should be outraged and seek solutions,” Daniel R. Levinson, inspector general of the Department of Health and Human Services, wrote in announcing the audit results. Mr. Levinson noted that such drugs — which include Risperdal, Zyprexa, Seroquel, Abilify and Geodon — are “potentially lethal” to many of the patients getting them and that some drug manufacturers illegally marketed their medicines for these uses “putting profits before safety.” The audit is an unusual assessment by the government of whether doctors are treating Medicare patients appropriately in nursing homes. Mr. Levinson suggested that the government should collect information on the diagnoses given Medicare patients so that the government can assess whether the drugs prescribed to them are appropriate. © 2011 The New York Times Company

Keyword: Alzheimers; Schizophrenia
Link ID: 15315 - Posted: 05.10.2011

By PERRI KLASS, M.D. The mother had brought in a note from her son’s elementary school teacher: Dear doctor, I think this child needs to be tested for attention deficit disorder. “She’s worried about how he can’t sit still in school and do his work,” the mother said. “He’s always getting into trouble.” But then she brightened. “But he can’t have attention deficit, I know that.” Why? Her son could sit for hours concentrating on video games, it turned out, so she was certain there was nothing wrong with his attention span. It’s an assertion I’ve heard many times when a child has attention problems. Sometimes parents make the same point about television: My child can sit and watch for hours — he can’t have A.D.H.D. In fact, a child’s ability to stay focused on a screen, though not anywhere else, is actually characteristic of attention deficit hyperactivity disorder. There are complex behavioral and neurological connections linking screens and attention, and many experts believe that these children do spend more time playing video games and watching television than their peers. But is a child’s fascination with the screen a cause or an effect of attention problems — or both? It’s a complicated question that researchers are still struggling to tease out. © 2011 The New York Times Company

Keyword: ADHD; Attention
Link ID: 15314 - Posted: 05.10.2011

By ALASTAIR GEE OXFORD, England — The task given to participants in an Oxford University depression study sounds straightforward. After investigators read them a cue word, they have 30 seconds to recount a single specific memory, meaning an event that lasted less than one day. Cues may be positive (“loved”), negative (“heartless”) or neutral (“green”). For “rejected,” one participant answered, “A few weeks ago, I had a meeting with my boss, and my ideas were rejected.” Another said, “My brothers are always talking about going on holiday without me.” The second answer was wrong — it is not specific, and it refers to something that took place on several occasions. But in studies under way at Oxford and elsewhere, scientists are looking to such failures to gain new insights into the diagnosis and treatment of depression. They are focusing not on what people remember, but how. The phenomenon is called overgeneral memory, a tendency to recall past events in a broad, vague manner. “It’s an unsung vulnerability factor for unhelpful reactions when things go wrong in life,” said Mark Williams, the clinical psychologist who has been leading the Oxford studies. Some forgetting is essential for healthy functioning — “If you’re trying to remember where you parked the car at the supermarket, it would be disastrous if all other times you parked the car at the supermarket came to mind,” said Martin Conway, a cognitive psychologist at the University of Leeds in England. But, a chronic tendency to obliterate details has been linked to longer and more intense episodes of depression. © 2011 The New York Times Company

Keyword: Depression; Learning & Memory
Link ID: 15313 - Posted: 05.10.2011

by Catherine de Lange You might think that being able to distinguish between a noise associated with danger and a similar but innocuous one would be a useful skill. Yet people find it hard to tell similar sounds apart if one is linked to a bad experience. The finding could help explain how people with post-traumatic stress disorder (PTSD) may become hypersensitive to certain types of sound. Rony Paz and colleagues from the Weizmann Institute of Science in Rehovot, Israel, repeatedly played one of two tones to volunteers. One group heard a tone followed by an unpleasant smell, the other a tone followed by a pleasant, melon-like odour. The team then tested how well each person could distinguish between the tones they had heard and similar sounds. On average, those who had heard the sound that was followed by an unpleasant smell performed worse at this task. The effect persisted 24 hours later. Evolutionary sense This makes sense from an evolutionary point of view, says Paz. "If you hear a lion and you see a zebra get eaten, that should be enough for you to know that a lion is bad and to avoid it." If you subsequently hear a different lion, you want your system to respond quickly to the threat rather than try to distinguish between the two lions. Paz thinks this conditioning may involve rewiring of the amygdala, the part of the brain which controls the fear response. Understanding this mechanism could lead to better treatments for PTSD, he says. Journal reference: Nature Neuroscience, DOI: 10.1038/nn.2802 © Copyright Reed Business Information Ltd.

Keyword: Emotions; Hearing
Link ID: 15312 - Posted: 05.10.2011

Tiffany O'Callaghan, CultureLab editor AS ANIMAL behaviourist Jonathan Balcombe sees it, too often the animal kingdom is portrayed solely as a realm of dire and perpetual struggle for survival. He argues that observations of playfulness or expressions of pleasure by non-human creatures of all stripes, feathers and fins are depicted as nothing more than evolutionary adaptation. The Exultant Ark, his pictorial exploration of pleasure among creatures from primate to porpoise, challenges this idea. It intersperses glorious images of animals preening, grooming and gallivanting with snippets of studies suggesting such behaviours belie an overly utilitarian interpretation. Sleepy, full-bellied kittens snuggling up to their mothers, dozing sea otters drifting on their backs with linked paws, frolicking alpine ibex - Balcombe revels in images that convey intimacy, comfort and even love, terms usually reserved for humans. A key point for Balcombe, though, is that we must go beyond anthropomorphism to get to the root of what non-human animals feel. Balcombe laments the fact that scientific understanding of animal pleasure remains in its infancy, but cobbles together anecdotes and preliminary research to raise questions about animals' experience. For instance, in highlighting the relationship between hippos and the fish that scrounge between their toes and teeth, he explores its potential interpretation as a mutually enjoyable experience. © Copyright Reed Business Information Ltd.

Keyword: Emotions; Evolution
Link ID: 15311 - Posted: 05.10.2011

• Kat Arney Last month US clothing retailer J Crew released photos showing the company's president, Jenna Lyons, painting her 5-year-old child's toenails their favourite shade of hot pink. No big deal, you might think, until you notice the child is a boy. The ensuing media kerfuffle highlights what anyone from a toddler to Dame Barbara Cartland could have told you. Pink is a girl's colour, and is certainly not fit for a boy's toenails. Take a trip to a toy store and you'll see this gender divide writ large in the aisles. On one side, the boys' toys – Lego and other construction kits, pirate costumes, toy guns, racing cars and so on – boxed in blue and other "manly" colours and illustrated with pictures of boys. Turn a corner, and you're assaulted by a wall of pink built from Barbie dolls, multi-packs of miniature high heels, princess outfits and tea sets. The message is clear: these are boys' toys, and those are girls' toys. And in this particular battle of the sexes, there's very little neutral territory. Many people – such as the Pink Stinks campaign – are fighting against the power of pink. In response to complaints about the pink/blue divide in their wares, toy retailer the Early Learning Centre points vaguely to research showing that "gender is a major factor in determining children's colour preferences, with most boys typically preferring blue and girls preferring pink from infancy." But is this really true? And does it even matter? Together with radio producer Jolyon Jenkins, I've been searching for the scientific truth behind the rampant pinkification of toys for girls. © Guardian News and Media Limited 2011

Keyword: Sexual Behavior; Emotions
Link ID: 15310 - Posted: 05.10.2011

Erin Allday, Chronicle Staff Writer Jeanne Nollman was a later bloomer. She waited and waited for puberty to hit, and when she was 17 and still nothing had happened, she got tested - and found out she had a rare condition called Swyer syndrome and would need supplemental hormones. What no one told her until eight years later, when she demanded more information about her condition, was that she had the male X-Y chromosome pattern. "That was typical back then, in the '70s," said Nollman, who is now 51 and lives in San Leandro with her husband and two adopted teenage children. "I guess they thought I might go jump off a roof and commit suicide with this information. But I must be an odd duck because I was just relieved." Now she's trying to help other children - and their parents - learn about and even embrace their "disorder of sex differentiation," or DSD, which is the medical term for hermaphrodite, a word that is no longer used by doctors and patients. The Bay Area is getting its first DSD parent support group next week, with a meeting Thursday at UCSF. Organizers, including Nollman, hope the group will become a resource for families to talk openly about the unique problems that come with raising kids who have sex development disorders. Such disorders, which may occur in as many as 1 in 3,000 births, include a wide variety of conditions, from something that's not obvious at birth, like Swyer syndrome, to babies born with ambiguous genitalia who cannot immediately be labeled male or female. © 2011 Hearst Communications Inc.

Keyword: Sexual Behavior
Link ID: 15309 - Posted: 05.10.2011

Jeff Warren “If you get into any trouble, try concentrating on your breath. Sometimes the breath is all you have.” Brian looked concerned, though he also looked weirdly elongated, ­so it was hard to tell what was actually happening. I was on drugs, you see, and not just any drug. Thirty minutes earlier I had gulped back a cupful of ayahuasca, a plant-based hallucinogen that William Burroughs—no slouch when it came to chemical experimentation—once described as the most powerful he had ever experienced. This was my third trip in six days, and I’d taken half again as much as anyone else in the group. Now nobody would look me in the eye. This was several years ago, during a perspective-altering ten-day workshop in South America. Today, most armchair adventurers will have heard of ayahuasca, which first escaped from the Amazon jungle in the 1930s and has recently leapt from underground curiosity to zeitgeist sensation. Following in the footsteps of celebrities such as Sting and Oliver Stone, every year thousands of people fly to countries like Peru, Brazil and Ecuador, where ayahuasca can be sampled in the company of professional shamans—some respectable, some not. Having had their fill of physical travel, Westerners now want to sail right out of their minds. Others quaff more locally. British Columbia’s Pender Island, Toronto’s beaches and Montreal’s suburbs host gatherings of the curious (supervised by imported boutique shamans) and congregations of the two fastest-growing syncretic churches that use ayahuasca as a sacrament: the Santo Daime and the União do Vegetal. Both churches—part animist, part Christian—have outposts across Latin America, Europe and North America; none other than Jeffrey Bronfman, third-generation member of the famous Montreal whisky family, heads the Santa Fe chapter of the União do Vegetal. Ayahuasca’s precise legal status in the US and Canada is ambiguous. But, if you’re determined, getting your hands on the stuff isn’t hard. © 2010 Maisonneuve Magazine

Keyword: Drug Abuse
Link ID: 15308 - Posted: 05.10.2011

By ALAN SCHWARZ When the N.F.L. veteran Andre Waters killed himself in late 2006, the subsequent discovery of damage in his brain shocked the football community into asking how many other retired players might have an incurable disease. After the recent suicide of Dave Duerson, however, and last Monday’s announcement that he also had chronic traumatic encephalopathy, the brain damage formerly associated with boxers, the finding shocked no one. Duerson became the 14th retired N.F.L. player — of 15 examined by Boston University researchers — to test positive for the condition. Waters and Duerson bookend a remarkable shift in the understanding of football brain trauma: four years after a few positive tests begged explanation, questions mainly surround the absence of negatives. “It makes you worry as a player — I would imagine all of us have it,” said Chidi Ahanotu, 40, who played defensive lineman mostly for Tampa Bay from 1993 to 2004. “To what degree, I don’t know. But I don’t know how you can’t think that.” So far, though, each successive case of C.T.E. has said more about the existence of the disease than the true breadth of it. The set of 15 players tested by B.U. researchers to this point is far from a random sample of N.F.L. retirees that could represent the wider population. Many of the players died under conditions that could be related to C.T.E.: Waters and Duerson by suicide, John Grimsley from a gun accident, Tom McHale from a drug overdose. Their families then donated the brains largely to seek an explanation for their behavior. © 2011 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 15307 - Posted: 05.09.2011

By BRYSON VOIRIN The morning after our first successful frigate bird capture, I slowly creep through the thorny brush toward the field tent to check up on the female. It’s been about 12 hours since I put her back on her nest with a sleep logger and GPS unit, and I’m keen to see how she is doing, and if she is still here or if she has switched with her mate and is out foraging. Gazing through my binoculars, I spot her, sitting alert on her nest. I breathe a deep sigh of relief, knowing that her late-night capture did not cause nest abandonment. As in any zoology fieldwork, our first priority is the well-being of our study species. Before starting any project with animals, there is a stringent animal care committee that reviews and approves our protocols and procedures. Even though previous work on frigate birds shows that the birds would not be spooked off their nests, seeing this confirmed the morning after is a welcome sign. Her sleep logger is still attached and looking fine, held on by the curious skin glue. I watch her head movements as she follows other birds floating overhead; she doesn’t seem affected at all by the device. However, judging by the angry glare she gives me, my presence is making her nervous. I want to avoid stressing the female any more than necessary, so I head back to camp and leave her alone for the rest of the day. The next morning Sebastian Cruz reports back that a male has switched with her on the nest, meaning that she is out foraging. By the pinkish color of his throat we can tell that this is her nesting mate. Had she abandoned her nest, and another male taken over, that male would have a bright red inflated gular sac. © 2011 The New York Times Company

Keyword: Sleep; Evolution
Link ID: 15306 - Posted: 05.09.2011

By CLAUDIA WALLIS An ambitious six-year effort to gauge the rate of childhood autism in a middle-class South Korean city has yielded a figure that stunned experts and is likely to influence the way the disorder’s prevalence is measured around the world, scientists reported on Monday. The figure, 2.6 percent of all children aged 7 to 12 in the Ilsan district of the city of Goyang, is more than twice the rate usually reported in the developed world. Even that rate, about 1 percent, has been climbing rapidly in recent years — from 0.6 percent in the United States in 2007, for example. But experts said the findings did not mean that the actual numbers of children with autism were rising, simply that the study was more comprehensive than previous ones. “This is a very impressive study,” said Lisa Croen, director of the autism research program at Kaiser-Permanente Northern California, who was not connected with the new report. “They did a careful job and in a part of the world where autism has not been well documented in the past.” For the study, which is being published in The American Journal of Psychiatry, researchers from the Yale Child Study Center, George Washington University and other leading institutions sought to screen every child aged 7 to 12 in Ilsan, a community of 488,590, about the size of Staten Island. By contrast, the Centers for Disease Control and Prevention in the United States and most other research groups measure autism prevalence by examining and verifying records of existing cases kept by health care and special education agencies. That approach may leave out many children whose parents and schools have never sought a diagnosis. © 2011 The New York Times Company

Keyword: Autism
Link ID: 15305 - Posted: 05.09.2011

Matt Kaplan Modern mammals often live in groups, but most marsupials are solitary. With no fossil evidence to suggest that the animals have ever behaved otherwise, palaeontologists have long assumed that marsupials have been loners throughout their evolutionary history. This notion is now being overturned by the analysis of a fossil site containing many marsupials that seem to have been living together. The site, in the Tiupampa locality of Bolivia, contains 35 specimens of Pucadelphys andinus, a primitive opossum from the early Palaeocene Epoch (64 million years ago). Teeth are usually all that palaeontologists can find of ancient mammals, because dentition is built to endure punishment, and fossilizes well. However, 22 of the 35 specimens at the Bolivian site consist of teeth, skulls and body skeletons in near-perfect shape. Sandrine Ladevèze, a palaeontologist at the Royal Belgian Institute of Natural Sciences in Brussels, and her colleagues publish an analysis of the specimens today in Nature1. "To find a sample of this quality is almost unheard of," says Richard Cifelli, a palaeontologist at the University of Oklahoma in Norman. Full house But it is not the condition, but the placement of the specimens at the fossil site that intrigued Ladevèze. © 2011 Nature Publishing Group

Keyword: Evolution
Link ID: 15304 - Posted: 05.09.2011

By Ella Davies Stress may play a crucial role in determining whether some birds mimic the sounds of others, say researchers. Scientists studied the vocal repertoire of bowerbirds. Best known for their elaborate nests or "bowers", the birds can also copy up to fifteen sounds. Bowerbirds were previously thought to mimic predators as a form of defence. But recordings reveal they prefer to copy a variety of alarm calls made by bird species that are either bullying each other, or which feel threatened. That suggests that the birds learn and reproduce calls only in stressful situations, say the researchers. Spotted bowerbirds (Ptilonorhynchus maculatus) are found in Australia and New Guinea and are best known for their elaborate "bowers", created by males seeking to impress a mate. Reports from egg collectors led scientists to believe the birds mimicked the calls of predators as a way of defending their territory. However, researchers from the University of St Andrews, UK and Deakin University, Geelong, Victoria, Australia found different results in their study. They have published details in the journal Naturwissenschaften. BBC © 2011

Keyword: Stress; Language
Link ID: 15303 - Posted: 05.09.2011

By Katherine Harmon The people we associate with can have a powerful effect on our behavior—for better or for worse. This holds true for human health and body mass, too. The heavier our close friends and family, the heavier we are likely to be. This correlation, described in 2007 by a team that analyzed data from the longitudinal Framingham Heart Study, is well established. But just how this transpires—whether via shared norms, common behavior or just similar environments—has been the subject of much debate. The authors of the 2007 study proposed that social norms shared among friends and relatives might be a strong determinant of body mass index (BMI). And a new study, published online May 5 in the American Journal of Public Health, drills down to see just how these social forces might be at work. The study of more than 100 women—and hundreds of their friends and family members—however, suggests that social attitudes might not be key in determining obesity clusters after all. "Going in as anthropologists we assumed that the norms would have a strong influence" on BMI, says Alexandra Brewis, executive director of the School of Human Evolution and Social Change at Arizona State University in Tempe. She and her colleagues found themselves surprised how small an effect the norms had on a person's BMI. Just one type of social dynamic seemed to play a statistically significant role—and that was only about 20 percent. © 2011 Scientific American,

Keyword: Obesity
Link ID: 15302 - Posted: 05.07.2011

By Bruce Bower Depression may have an analytical upside. People hospitalized for this mood disorder display a flair for making good choices when many options must be considered one at a time, a new study finds. Depression may prompt an analytical thinking style suited to solving sequential problems, such as deciding when to stop a house hunt and purchase a property or when to stop playing the field and marry a suitor, say psychologist Bettina von Helversen of the University of Basel in Switzerland and her colleagues. It’s also possible that depressed people adopt a pessimistic outlook that encourages a thorough evaluation of available options, von Helversen's team suggests in an upcoming Journal of Abnormal Psychology. “Depression may improve sequential decision making, which includes some high-stakes choices,” she says. Von Helversen’s study is the first to demonstrate a thinking advantage for clinically depressed patients, possibly because — unlike previous studies of people with the ailment — the team used a quantitative measure to evaluate the accuracy of realistic social choices, remarks psychologist Paul Andrews of Virginia Commonwealth University in Richmond. Andrews hypothesizes that depression evolved as an emotional response that induces people to isolate themselves and single-mindedly resolve painful personal problems. “Depressive cognition is more complex than has been assumed by clinicians,” he says. © Society for Science & the Public 2000 - 2011

Keyword: Depression
Link ID: 15301 - Posted: 05.07.2011

By Susan Gaidos Emery Brown knows how to take the sting out of surgery. As an anesthesiologist, he has steered hundreds of patients to pain-free oblivion, allowing doctors to go about their business resetting bones, repairing heart valves or removing tumors. During surgery he continually monitors his patients, keeping tabs on their heart rate, blood pressure and breathing. Recently, he has also been eyeing what happens in their brains. Rather than going under the knife, some of the people in Brown’s care are going into scanners to reveal how the brain responds when people are knocked out. These deep glimpses could answer vexing questions about how people enter the state of unconsciousness known as general anesthesia and what happens in the brain while they are there. Although it is widely used and remarkably effective, anesthesia’s neural mechanisms have long remained mostly mysterious. While every anesthetic drug has its own effect, scientists know little about how the various versions work on the brain to transport patients from normal waking awareness to dreamless nothingness. Understanding how such compounds meddle with the nervous system might lead to anesthetics capable of tweaking neural circuits more precisely, delivering only what is needed where it’s needed, says Brown, of Massachusetts General Hospital in Boston. Fine-tuning the drugs’ effects could also help doctors bring patients into and out of consciousness more quickly and safely, avoiding the side effects that can occur when medications act at brain sites other than those intended or act at targeted sites for too long a time. © Society for Science & the Public 2000 - 2011

Keyword: Sleep
Link ID: 15300 - Posted: 05.07.2011