NEW YORK - How well people get around and keep their balance in old age is linked to the severity of changes in their brains, new research suggests. Age-related white matter brain changes, also called leukoaraiosis, are frequently seen in older people and differ in severity, and the new study suggests that they are associated with gait and balance disturbances. Neurologists, geriatricians and family doctors often send older patients for brain scans to rule out severe brain atrophy (wasting), a tumor, stroke or brain infection because of mild mental difficulties, unsteadiness or depressed mood, and get back white matter changes as the main finding, Dr. Hansjoerg Baezner told Reuters Health. Baezner, from University of Heidelberg in Mannheim, Germany, and colleagues studied the impact of age-related white matter changes on functional decline in 639 men and women between the ages of 65 and 84 who underwent brain scans as well as walking and balance tests. Of the group, 284 had mild age-related white matter changes, 197 moderate changes, and 158 severe changes. They found that people with severe white matter changes were twice as likely to score poorly on tests of walking and balance as those with mild white matter changes. They further found that people with severe changes were twice as likely as the mild group to have a history of falls. The moderate group was one-and-a-half times as likely as the mild group to have a history of falls. Copyright 2008 Reuters.

Keyword: Development of the Brain; Alzheimers
Link ID: 11431 - Posted: 03.18.2008

By C. CLAIBORNE RAY Q. Does oversleeping make one feel more tired than sleeping a normal seven to eight hours? A. That depends on what is meant by oversleeping, said Dr. Charles P. Pollak, director of the Center for Sleep Medicine at NewYork-Presbyterian Hospital/Weill Cornell Medical Center. A long period of sleep may be just what the doctor ordered. “People do not necessarily sleep a long time arbitrarily,” Dr. Pollak said. “Sometimes it is in response to insufficient sleep. People make up for lost sleep on the weekend, and the sleep may be very long. But that is not the same as oversleeping. It does not contribute to feeling groggy and tired, but helps make up for sleep you should have been getting during the week.” Dr. Pollak explains that most people cannot sleep more than the amount they need, which varies a great deal from person to person and from age to age. “Extending sleep beyond what is normally required might sometimes make you feel groggy,” he said, “but it is not easy to do.” “There is such a thing as being sleep-deprived,” he continued. “But as far as we know, there is no such thing as being wake-deprived. If you awake feeling refreshed, that is how much sleep you actually require.” Copyright 2008 The New York Times Company

Keyword: Sleep
Link ID: 11430 - Posted: 06.24.2010

For identical twins, the equation always has been simple: same egg + same sperm = same DNA. But new research from the American Journal of Human Genetics says this formula is not quite right. According to geneticist Jan Dumanski and his colleagues, identical twins don't have matching DNA. "In medical textbooks or in popular science books, it's very often written that identical twins are identical also in the DNA," says Dumanski. "And that's not true. We are challenging this dogma by finding these small subtle but clearly detectable differences in the DNA of identical twins." Although researchers previously have documented a few, rare genetic differences between identical twins, Dumanski says such cases were considered exceptions. "It was, in the field, considered rather as a curiosity that they really differ. What we show is that these differences are actually very, very frequent," he explains. "We basically see those differences in every twin pair we looked at so far." For their study, Dumanski and colleagues compared the genomes of 19 twin pairs using DNA chip technology. For some of their volunteer pairs, one twin had Parkinson's disease while the other was healthy. Until now, scientists would attribute such a difference to environment rather than genetics. But Dumanski's research shows genetics might play a role. © ScienCentral, 2000-2008.

Keyword: Genes & Behavior
Link ID: 11429 - Posted: 06.24.2010

By NATALIE ANGIER You can accuse the disgraced ex-governor Eliot Spitzer of many things in his decision to flout the law by soliciting the services of a pricey prostitute: hypocrisy, egomania, sophomoric impulsiveness and self-indulgence, delusional ineptitude and boneheadedness. But one trait decidedly not on display in Mr. Spitzer’s splashy act of whole-life catabolism was originality. It’s all been done before, every snickering bit of it, and not just by powerful “risk-taking” alpha men who may or may not be enriched for the hormone testosterone. It’s been done by many other creatures, tens of thousands of other species, by male and female representatives of every taxonomic twig on the great tree of life. Sexual promiscuity is rampant throughout nature, and true faithfulness a fond fantasy. Oh, there are plenty of animals in which males and females team up to raise young, as we do, that form “pair bonds” of impressive endurance and apparent mutual affection, spending hours reaffirming their partnership by snuggling together like prairie voles or singing hooty, doo-wop love songs like gibbons, or dancing goofily like blue-footed boobies. Yet as biologists have discovered through the application of DNA paternity tests to the offspring of these bonded pairs, social monogamy is very rarely accompanied by sexual, or genetic, monogamy. Assay the kids in a given brood, whether of birds, voles, lesser apes, foxes or any other pair-bonding species, and anywhere from 10 to 70 percent will prove to have been sired by somebody other than the resident male. Copyright 2008 The New York Times Company

Keyword: Sexual Behavior
Link ID: 11428 - Posted: 06.24.2010

Michael Hopkin How do we know what another person is thinking? New research suggests we use the same brain region that we do when thinking about ourselves — but only as long as we judge the person to be similar to us. When second-guessing the opinions and feelings of those unlike ourselves, this brain region does get involved, the new research shows. This may mean we are more likely to fall back on stereotyping — potentially helping to explain the causes of social tensions such as racism or religious disputes. Neuroscientists led by Adrianna Jenkins of Harvard University in Cambridge, Massachusetts, made the discovery when trying to deduce how the brain weighs up the thoughts of others. As Jenkins explains, judging how others are feeling is a valuable social skill, because we have no way of seeing inside another person's head. "How do we go about bridging the gap between our minds and others' minds?" Jenkins asks. The answer seems to be that it depends on whether we feel we identify with that person or not, Jenkins says. In other words, how our brain handles the question of someone's attitude to anything, from traffic jams to impressionist art, depends entirely on how we feel we relate to them as a person. © 2008 Nature Publishing Group

Keyword: Emotions; Autism
Link ID: 11427 - Posted: 06.24.2010

A drug to tackle two of the leading causes of blindness is a step closer after successful experiments in mice. Activating a specific protein in the eyes prevented blood vessel damage which can cause sight loss. The research has implications for macular degeneration and diabetic retinopathy - two common conditions associated with blood vessel problems. The University of Utah study, published in Nature Medicine, could also provide clues for treating other diseases. Both of the types of eye problems are common in older people, and involve both leakage of blood vessels within the eye, and the formation of abnormal new blood vessels. Researchers had already identified a protein called Robo4, which appeared to play an important role in the development of stable, working blood vessels. The proteins were activated in mice bred to mimic the effects of age-related macular degeneration (AMD) and diabetic retinopathy. The scientists saw that the blood vessel damage was prevented, or in some cases, reversed. While this does not prove that the same principle works in humans, or that a drug could be developed to harness this without side-effects, the researchers described the work as a "major breakthrough". Professor Randall Olson, director of Utah's John A Moran Eye Center, said: "We are excited about taking this opening and moving the frontier forward with real hope for patients who have but few, often disappointing options." The scientists believe that it will still take some years before a working drug can be provided for patients. Dr Hemin Chin, from the US National Eye Institute, said: "Given that vascular eye diseases, such as age-related macular degeneration and diabetic retinopathy, are the number one cause of vision loss in the US, the identification of new signalling pathways that prevent abnormal vessel growth and leakage in the eye represents a major scientific advancement." (C)BBC

Keyword: Vision
Link ID: 11426 - Posted: 03.17.2008

CHICAGO - Ballet teacher Gayle Parseghian thought she might never dance again after a back injury while moving heavy furniture left her with unrelenting pain. But an intensive, four-week “boot camp” got the 55-year-old dancer from Toledo, Ohio, back to the barre. The program at the Rehabilitation Institute of Chicago taught her to manage the chronic pain that had tormented her for more than a year. “It affects your relationship with your spouse, your family, your friends, your boss,” she said. “It’s like you’re trapped in your body and you can’t get out. It’s a feeling of being completely out of control.” New research suggests chronic pain affects the brain’s ability to rest, disrupting a system that normally charges up some brain regions and powers down others when a person relaxes. “I ask a patient who has had chronic pain for 10 years to put the mind blank, don’t think about anything,” says Dr. Dante Chialvo, a researcher at Northwestern University’s Feinberg School of Medicine who is not involved with the boot camp. MRI images show the pain sufferer’s brain lighting up, but not as a normal brain at rest would, he said. “There is an objective biological difference in the brain.” The early findings could explain the sleep disturbances, decision-making problems and mood changes that often accompany chronic pain, he said. © 2008 The Associated Press.

Keyword: Pain & Touch
Link ID: 11425 - Posted: 06.24.2010

By ALEXANDER STAR Why do horses snort? Sometimes, at the approach of a stranger or the appearance of a plane high above the pasture, a horse will widen its eyes, flare its nostrils and send a stuttering column of air out into the world. On other occasions, horses have been known to snort for no reason besides their own boredom. By suddenly creating a sound, the slack-minded horse elicits an automatic “startle response” — flooding its brain with chemicals, delivering a jolt of excitement and relieving, at least for a moment, the monotony of a long day in an empty field. The horse has in effect fooled its own nervous system — and benefited from the self-deceit. If horses can alter their own brain chemistries at will (and have good reasons to do so), what about human beings? In “On Deep History and the Brain,” Daniel Lord Smail suggests that human history can be understood as a long, unbroken sequence of snorts and sighs and other self-modifications of our mental states. We want to alter our own moods and feelings, and the rise of man from hunter-gatherer and farmer to office worker and video-game adept is the story of the ever proliferating devices — from coffee and tobacco to religious rites and romance novels — we’ve acquired to do so. Humans, Smail writes, have invented “a dizzying array of practices that stimulate the production and circulation of our own chemical messengers,” and those devices have become more plentiful with time. We make our own history, albeit with neurotransmitters not of our choosing. Copyright 2008 The New York Times Company

Keyword: Evolution; Drug Abuse
Link ID: 11424 - Posted: 06.24.2010

Celeste Biever A virtual child controlled by artificially intelligent software has passed a cognitive test regarded as a major milestone in human development. It could lead to smarter computer games able to predict human players' state of mind. Children typically master the "false belief test" at age 4 or 5. It tests their ability to realise that the beliefs of others can differ from their own, and from reality. The creators of the new character – which they called Eddie – say passing the test shows it can reason about the beliefs of others, using a rudimentary "theory of mind". "Today's [video game] characters have no genuine autonomy or mental picture of who you are," researcher Selmer Bringsjord of Rensselaer Polytechnic Institute in Troy, New York, told New Scientist. He aims to change that with future games and virtual worlds populated by genuinely intelligent computer characters able to predict and understand players actions and motives. Bringsjord's colleague Andrew Shilliday adds that their work will have applications outside of gaming. For example, search engines able to reason about the beliefs of a user might allow them to better understand their search queries. © Copyright Reed Business Information Ltd.

Keyword: Robotics; Autism
Link ID: 11423 - Posted: 06.24.2010

By Nikhil Swaminathan When Deb Roy and his wife have guests over to see their two-and-a-half-year-old son—the couple is withholding his name to protect his privacy—the first thing they do is ask their visitors to fill out a consent form. Unusual, for sure, but the couple is merely trying to make people aware that their actions and voices may be captured by the 11 fish-eye cameras and 14 microphones hidden around their Cambridge, Mass., home listening in on nearly every sound their son has ever uttered. The short-term goal is to understand how children acquire language; the long-term goal is to use the intelligence gleaned to teach robots to talk, too. Roy, 39, head of the cognitive machines group at the Massachusetts Institute of Technology's Media Lab, is documenting every parent–child "conversation" in what he calls the Human Speechome Project. He estimates that by the time he finishes the recording phase of the project later this year, he will have collected an estimated 200,000 hours of video and multitrack audio data—or about 70 percent of the child's first two years of waking life, along with part of year three. Roy initiated the project after hitting a dead-end in his robotics research. As a graduate student at M.I.T.'s Media Lab, he wanted to teach a robot to talk, so he programmed one of his creations (named Toco) with sophisticated image and speech processing software combined with machine-learning algorithms that he hoped would do the trick. But when Roy placed a ball in front of Toco's camera, he realized the machine could not fathom the difference between the meaning of "ball" (the object) and "round" (the object's property), both of which were represented the same way in its computer memory. © 1996-2008 Scientific American Inc.

Keyword: Language; Robotics
Link ID: 11422 - Posted: 06.24.2010

Heidi Ledford Networks of genes linked to obesity have been uncovered.GettyResearchers have used a new technique to identify networks of genes linked to obesity in both mice and humans. The procedure is more comprehensive than the traditional method of hunting for genes associated with disease, and is already being used to identify new drug targets. Over the past year, a flurry of studies have revealed genetic variations associated with disease. These ‘genome-wide association studies’ have been used to find variants associated with everything from heart disease to diabetes (See Genome studies: Genetics by numbers). Traditionally, single genes are linked with particular diseases by locating genetic variants present in people who have the disease and identifying the part of a chromosome associated with that disease. Then researchers have to track down the gene on the chromosome, without knowing what it does or why it would be involved. Eric Schadt of Rosetta Inpharmatics, a subsidiary of Merck Pharmaceuticals in Seattle, Washington, lead one of the research teams involved in the new work. He likens the traditional approach to finding a simple light switch for a disease: flipping this single gene switch on or off may produce a higher or lower risk of disease. The new approach looks at changes in expression of already-known genes, and finds networks of genes associated with disease, rather than single switches. “Instead of the simple ‘turn the light on or off’ analogy, we would view this as a network of these switches,” says Schadt. © 2008 Nature Publishing Group

Keyword: Genes & Behavior; Obesity
Link ID: 11421 - Posted: 06.24.2010

Steve Heilig The human brain has become a sexy subject, with unprecedented amounts of money going toward neuroscience research and ever more books and articles on our gray matter. And when an author such as Tom Wolfe turns his attention to the topic, that makes it official. In 1996, he wrote about emerging controversies in neuroscience for Forbes. That essay, "Sorry, But Your Soul Just Died" (reprinted in his 2001 collection "Hooking Up"), remains fascinating reading. He is now at work on a book related to the topics he explored in that essay. It will be called "The Human Beast," which was the title of a book by Emile Zola published in 1890, influenced directly by Darwin's doctrine, which, Wolfe points out, "was then barely 30 years old." As one of the most widely read authors of our time, Wolfe is renowned for best-selling books such as "The Right Stuff," "The Bonfire of the Vanities," "The Electric Kool-Aid Acid Test," and "A Man in Full." Wolfe-ian terms like "the right stuff," "radical chic," "the Me Decade" have become popular phrases, even among those who have never read his work. He's been called "America's greatest living novelist," and the late, great Kurt Vonnegut called Wolfe a genius. His insights - often scathing, humorous or both - into popular trends and thought have made him one of our leading chroniclers of modern culture. © 2008 Hearst Communications Inc.

Keyword: Language; Genes & Behavior
Link ID: 11420 - Posted: 06.24.2010

Susan Brown Seeing in the dark: 'whiskers' help these birds to sense their surroundings.Ian JonesFancy feathers are usually thought to be just ornaments, but a pair of biologists has shown that a little seabird uses the plumes on its head like a cat’s whiskers to feel its way through dark crevices. Aptly named whiskered auklets (Aethia pygmaea ) breed on the volcanic Aleutian and Kuril Islands that rim the north Pacific. They lay their eggs in small chambers reached by narrow passageways through jagged lava rocks, which they enter and leave only at night. Whiskered auklets are the most elaborately decorated of the six known species of auklet, and are one of only two that are nocturnal. Striking stiff white feathers protrude from above and below the eyes of the otherwise slate-grey bird, and a dark plume swoops forward from the top of its head. Sampath Seneviratne and Ian Jones of Memorial University in St John’s, Newfoundland, Canada, wondered whether that array of feathers might provide a sense of touch to guide the birds in the dark. © 2008 Nature Publishing Group

Keyword: Pain & Touch
Link ID: 11419 - Posted: 06.24.2010

By Rob Stein Imagine this: You're lying on the operating table, apparently unconscious. The surgeon is cutting. But you're still awake. Not only that, you're paralyzed by the drugs the anesthesiologist gave you and can't speak out. That horrifying experience happens to between 20,000 and 40,000 Americans every year, leaving many -- not surprisingly -- severely traumatized. Now, a study in today's issue of the New England Journal of Medicine is raising questions about a monitor used by about 60 percent of U.S. operating rooms in an effort to prevent these frightening cases. The study involved 1,941 patients who underwent operations at the Barnes-Jewish Hospital in St. Louis. Anesthesiologists monitored half the patients with a system called BIS (bispectral index system) that analyzes brain waves so doctors can supposedly tell if a patient isn't totally unconscious or is starting to wake up. For the other half of the patients in the study, doctors simply paid especially close attention to the dosages of anesthesia. An equal number in each group -- two -- turned out to have been awake for at least part of their operations. One 51-year-old patient being monitored by BIS came to during pancreatic surgery and felt "white-hot fire pain" in his abdomen and his "organs and intestines moving around," the researchers wrote. He remembers "crying and thinking, 'If someone can see my crying, then someone can help me.' " © 2008 The Washington Post Company

Keyword: Pain & Touch; Sleep
Link ID: 11418 - Posted: 06.24.2010

By ALIYAH BARUCHIN A recent groundbreaking brain-imaging study found that children with attention-deficit hyperactivity disorder experience a development delay with a distinct biological basis. Investigators at the National Institute of Mental Health discovered that areas of the brain’s cortex undergo a thinning maturation process about three years later in children with A.D.H.D. than in those without the condition. Areas that integrate sensory information with executive functions like focused attention, remembering things from moment to moment and controlling movement — functions that are often compromised in people with A.D.H.D. — showed the longest lag time. The results of the study support the belief that A.D.H.D. is a delay in a normal pattern of development, rather than a deficit that completely derails development — a longstanding debate in A.D.H.D. research. Yet despite M.R.I. images showing biological brain differences in children with A.D.H.D., news of the findings immediately tapped into a wellspring of skepticism about the legitimacy of the condition. Web sites were inundated with postings that A.D.H.D. is “just a delay,” that kids diagnosed with the condition are actually “normal” after all, that it’s perverse to medicate children for something that “most” will outgrow. Estimated to affect millions of Americans — 3 percent to 7 percent of children and more than 4 percent of adults — A.D.H.D. has traveled an extraordinary arc of clinical and public opinion over the last four decades. What began as a relatively unknown disorder became broadly recognized as one of the most common psychiatric problems in children and an increasingly major consideration in adult psychiatric diagnoses as well. Copyright 2008 The New York Times Company

Keyword: ADHD
Link ID: 11417 - Posted: 06.24.2010

According to the American Pain Foundation, chronic pain affects 76.2 million Americans. Hillary Sweet is one of one them. Eight years ago she had successful treatment for breast cancer. But it aggravated some minor pain she had due to bone and nerve conditions, and Sweet’s pain became so intense that even lying down on a mattress was excruciating. After trying many therapies, nurse practitioner and researcher Pat Bruckenthal finally found a combination of treatments that relieve Sweet’s pain. Sweet sees Bruckenthal at the Pain Management and Headache Treatment Center of North Shore LIJ Health Systems. "I feel like I got my life back!" Sweet says. "I think she’s able to function and adapt to the fact that she has chronic pain very well. Not so for everybody," says Bruckenthal. Andreas Beutler, a researcher at Mount Sinai School of Medicine who also treats cancer patients, is seeking a better way to restore what chronic pain takes away. "Approximately 10 to 30 percent of patients with chronic pain from advanced cancer do not really get sufficient pain relief" or cannot tolerate side effects of high doses of narcotics like morphine, he says. "So they’re often in a very difficult situation of choosing to feel free of side effects or to control their pain, which is a very difficult situation for the patients and their families and for us as physicians." © ScienCentral, 2000-2008.

Keyword: Pain & Touch; Genes & Behavior
Link ID: 11416 - Posted: 06.24.2010

By Nikhil Swaminathan A new study may have been for (and about) the birds, but it also hints at how humans may have developed the ability to speak, potentially paving the way to one day to identifying the causes of speech deficiencies. Duke University scientists report in PLoS ONE this week that they attempted to pinpoint regions of the brain responsible for vocal skills by studying three types of birds (parrots, hummingbirds and songbirds) capable of picking up new songs and utterances as well as birds (zebra finches and ringed turtle doves) that lack the ability. Their findings: vocal pathways are always nestled in the same areas of the brain that control body movement. "The vocal learning system is embedded within [an] ancient pathway'" designed to handle motor function that, in birds, controls their wings and legs, says study co-author Erich Jarvis, an associate professor of neurobiology at Duke University. So how did some birds develop an ability to learn new sounds? Jarvis speculates that the ability evolved from motor function or, more specifically, that the original "wiring" in the pathway linked to limbs may have duplicated and connected to vocal organs in these birds. © 1996-2008 Scientific American Inc

Keyword: Language; Evolution
Link ID: 11415 - Posted: 06.24.2010

Anna Petherick Anyone who has sprayed their skin with the insect repellent DEET and then picked up a plastic water bottle has probably felt a twinge of concern as the bottle starts to disintegrate in their hands. A new study pinpointing exactly how the repellent works will hopefully lead the way to other chemicals that have the same (or better) insect-deterring effect without the inconvenience of dissolving plastic. DEET is a very effective mosquito repellent and, despite its material-destroying capabilities, is safe for use on skin. But it can be an irritant and is a strong solvent, so it should not be used near a tent, synthetic clothes or near an open wound. This makes it less convenient than more-natural but less-effective repellents, such as citronella. Now, Leslie Vosshall and her colleagues at The Rockefeller University in New York have pinpointed how DEET works. In mosquitoes, it stops neurons that sense human odours from working properly, they report in Science 1. It does not affect mosquitoes' abilities to sense carbon dioxide from human breath, as some people had suspected. The result should help researchers to scan a host of other chemicals for the same property, hopefully yielding a friendlier, effective repellent. © 2008 Nature Publishing Group

Keyword: Chemical Senses (Smell & Taste)
Link ID: 11414 - Posted: 06.24.2010

New Canadian research suggests chemical changes to genes may trigger the altered brain functions resulting in schizophrenia and bipolar disorder, a finding that may lead to better understanding and treatment of the conditions. "The DNA sequence of genes for someone with an illness like schizophrenia and for someone without a mental illness often look the same; there are no visible changes that explain the cause of a disease," Dr. Arturas Petronis, a senior scientist at Krembil Family Epigenetics Laboratory at the Centre for Addiction and Mental Health, said in a release. "But we now have tools that show us changes in the second code, the epigenetic code." The Toronto-based study, published in the March 3 edition of the American Journal of Human Genetics, identified a second genetic code of epigenetic changes — chemical changes to a gene that do not alter the DNA sequence — in individuals with the psychoses. These changes can trigger under-production or overproduction of the body's proteins, changing its functions. The researchers found evidence of total or partial silencing of genes responsible for communication with the brain, brain development and other processes linked to schizophrenia and bipolar disorder. © CBC 2008

Keyword: Schizophrenia; Genes & Behavior
Link ID: 11413 - Posted: 06.24.2010

With the backing of a billionaire, researchers today launched a project that builds on their earlier atlas of the mouse brain and goes after a challenge 2,000 times bigger: a 3-D genetic map of the human brain. And that's not all: They're planning to produce a similar map of the mouse spinal cord, as well as another atlas showing how the mouse brain develops from the fetus to adulthood. The multimillion-dollar effort could help researchers develop new treatments for maladies ranging from spinal cord injury to autism. Today's triple play marks a new phase for the Seattle-based Allen Institute for Brain Science, which was founded in 2003 with $100 million in seed money from software billionaire Paul Allen. The first phase of the Allen Brain Atlas focused on the mouse brain - and looked specifically at which genes were active in which areas of the brain. Genes in the brain serve as chemical switches, providing the instructions for making proteins that have various effects on brain chemistry. For example, a little oxytocin in just the right place gives you a warm, fuzzy feeling. A little less of a protein called p11 could leave you feeling depressed. Medical researchers can use information about gene expression to figure out the biochemistry behind activity in the various regions of the brain - and the institute says the information in its 180-terabyte online atlas gets a lot of use. © 2007 MSNBC.com

Keyword: Brain imaging; Genes & Behavior
Link ID: 11412 - Posted: 06.24.2010