By NICHOLAS WADE Do some of today's languages still hold a whisper of the ancient mother tongue spoken by the first modern humans? Many linguists say language changes far too fast for that to be possible. But a new genetic study underlines the extreme antiquity of a special group of languages, raising the possibility that their distinctive feature was part of the ancestral human mother tongue. They are the click languages of southern Africa. About 30 survive, spoken by peoples like the San, traditional hunters and gatherers, and the Khwe, who include hunters and herders. Each language has a set of four or five click sounds, which are essentially double consonants made by sucking the tongue down from the roof of the mouth. Outside of Africa, the only language known to use clicks is Damin, an extinct aboriginal language in Australia that was taught only to men for initiation rites. Copyright 2003 The New York Times Company

Keyword: Language; Evolution
Link ID: 3580 - Posted: 03.19.2003

As the brain sorts through the mountains of visual stimuli that it encounters every day, it shines a spotlight on conveniently located objects that could serve as tools, a new study shows. It is the first evidence that a passing glimpse of mundane--but potentially useful--tools can seize the brain's attention as dramatically as flashing lights and sudden motion. Stare directly at a screwdriver and the motor areas of your brain will get you ready to grasp it. But what about that hammer briefly spotted in the corner of your eye? Cognitive neuroscientist Todd Handy of Dartmouth College in Hanover, New Hampshire, and colleagues theorized that the brain's visual areas might check for graspable objects in peripheral vision in order to compute their location, size, and orientation, for example. Copyright © 2003 by the American Association for the Advancement of Science.

Keyword: Vision; Attention
Link ID: 3579 - Posted: 06.24.2010

In at least one type of endeavor, humans can't even begin to compete with their best friends. Dogs can be trained to sniff out drugs and explosives or to track down a crime suspect by smell. Why can't we do the same? Scientists from the Weizmann Institute of Science and the Max Planck Institute for Evolutionary Anthropology propose an explanation for this ancient quandary. All mammals, including humans, have about 1,000 genes encoding smell-detecting proteins, or olfactory receptors. These receptors, located in the mucous lining of the nose, identify scents by binding to molecules of odorous substances. However, not all olfactory receptor genes are functioning in all species. It is the percentage of the working olfactory genes that determines the sharpness of smell in animals and humans. In previous studies, the team of Prof. Doron Lancet of the Weizmann Institute's Molecular Genetics Department discovered that more than half of these genes in humans contain a mutation that prevents them from working properly. In a new study, published in the March 18, 2003 Proceedings of the National Academy of Sciences (PNAS), the scientists tackled the next question: is the genetic "loss" a relatively old phenomenon affecting all primates, or did it occurr only in humans?

Keyword: Chemical Senses (Smell & Taste); Evolution
Link ID: 3578 - Posted: 03.19.2003

(Bethesda, MD) – The phrase, “the right hand doesn’t know what the left hand is doing,” has its roots in a passage of the Bible (Matthew 6:3). If there is truth to this old saying, the reasons may have as much to do with the way the brain obtains information from the arms as it does from the observations of ancient scribes. Most individuals are either left- or right-handed. How the skills they have learned from the dominant arm (or hand) are transferred to the non-dominant arm have long intrigued physiologists and neurologists. Copyright © 2003, The American Physiological Society,

Keyword: Laterality
Link ID: 3577 - Posted: 06.24.2010

New study may have implications for millions in search of the elusive “good night’s sleep” (Bethesda, MD) -- In movies and novels alike, much is made of the stage of sleep known as rapid eye movement (REM), since this is the phase of slumber in which dreams (good, bad, exotic) occur. Among the medical community, there is an increased appreciation for what is called “slow-wave” sleep, (also known as deep or delta-wave sleep), because this fourth stage of sleep can be difficult to attain. If one is awakened during the first three stages of sleep, they must repeat these stages again before reaching fourth stage or “delta-wave,” sleep. Once this latter stage is reached, muscles are relaxed, blood pressure drops, and the pulse and breathing are slower. According to the Sleep Research Center, other benefits to the body are accrued during slow-wave sleep, including: an increase of blood supply to the body; a decrease in body temperature thus preserving energy; a lowering of metabolic activity enabling tissue repair and growth; an increase of natural immune-system modulators; and a period in which the growth hormone secretions reach their peak, thus stimulating body growth and development. Copyright © 2003, The American Physiological Society

Keyword: Sleep; Hormones & Behavior
Link ID: 3576 - Posted: 06.24.2010

Anxiety has long been linked to substance abuse. It is the key psychological factor driving the impulse to drink alcohol and one of the first symptoms of alcohol withdrawal. Now, researchers at the University of Illinois at Chicago have discovered they can control the urge to drink in experimental animals by manipulating the molecular events in the brain that underlie anxiety. The study is published in the current issue of Alcoholism: Clinical and Experimental Research, the nation's premier journal covering substance abuse. The researchers found that a particular protein in the amygdala -- the area of the brain associated with emotion, fear and anxiety -- controlled the drinking behavior of laboratory animals.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 3575 - Posted: 03.19.2003

By Larry O'Hanlon, Discovery News — Just how aggressive — or phobic — your dog is has as much to with its breed as its owner, say Danish animal scientists. In a study of more than 4,300 dogs with behavior problems, younger owners with little understanding of dog breeds or training had more trouble with dog-to-dog aggression, poodles and retrievers came off as more easily scared and urban dogs were more aggressive than their rural counterparts. The study is in the April issue of the journal Preventative Veterinary Medicine. Copyright © 2003 Discovery Communications Inc.

Keyword: Aggression; Genes & Behavior
Link ID: 3574 - Posted: 06.24.2010

COLLEGE STATION, – Inside a drawer in Luis Rene Garcia's biology lab, tens of thousands of roundworms are bumping into one another, slithering together and breeding. For the tiny worms, known to science as C. elegans, it's all just another day on a laboratory petri dish. But somewhere in the writhing masses, Dr. Garcia suspects, lie clues to a mystery with large implications: Is some behavior hereditary? Garcia, an assistant professor of biology at Texas A&M University, is an expert in the sexual habits of C. elegans and the genes that apparently control the behaviors. Although the premise that heredity influences human behavior is controversial, it is more generally accepted in animals, Garcia says, especially when it involves base behaviors such as mating. He straddles the familiar nature-nurture debate, theorizing that genes set basic tendencies and the environment shapes the behaviors further. To begin testing his hypothesis, Garcia is deconstructing some of the most elemental of all behaviors in one of the world's simplest organisms.

Keyword: Genes & Behavior
Link ID: 3573 - Posted: 06.24.2010

La Jolla, Calif.-Research at the Salk Institute has identified a gene that may link certain pesticides and chemical weaponry to a number of neurological disorders, including the elusive Gulf War syndrome and attention deficit/hyperactivity disorder (ADHD). The finding, published in the March 17 online version of Nature Genetics, is the first to demonstrate a clear genetic link between neurological disorders and exposure to organophosphate chemicals; the gene is one that scientists had not studied in previous efforts to find connections between these chemicals and disease. Organophosphates include household pesticides as well as deadly nerve gases like sarin. Dr. Carrolee Barlow, who led the work at the Salk Institute and is now at Merck and Co., Inc., and her team, headed by Christopher Winrow, found in mice that organophosphate exposure inhibited the activity of a gene called neuropathy target esterase, or NTE. This inhibition either killed the mice before birth, or over time led to a range of behaviors very similar to ADHD. Some of the neurological problems also echoed many of the symptoms seen in Gulf War syndrome.

Keyword: ADHD; Genes & Behavior
Link ID: 3572 - Posted: 03.18.2003

A low-testosterone man newly married to a high-testosterone woman might seem destined to be henpecked but a Penn State study found that such a coupling actually produced a marriage where the wife provided better social support for her mate. Dr. Catherine Cohan, assistant professor of human development and family studies, says, "It's not necessarily the case that higher testosterone is all bad. Testosterone is related to assertiveness which can be good or bad depending on whether it is manifested as either aggression or being helping and outgoing." In the first study of married couples to measure both the wife's and the husband's testosterone level, Penn State researchers found that positive or negative communication depended on the combination of your own testosterone level (relative to others of your gender) and your spouse's testosterone level.

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 3571 - Posted: 03.18.2003

By MARY DUENWALD Of all the infirmities people dread in old age, dementia may be the scariest. Many people in their 90's fear declining mental faculties more than they fear death, researchers at the Mayo Clinic in Rochester, Minn., have observed. If someone lives to be that old, the thinking goes, Alzheimer's disease or some other form of dementia is practically inevitable. So it may be some comfort that half of the nonagenarians in a recent Mayo study were perfectly alert. About 12 percent had significant memory problems, but were clearheaded enough to live independently and manage daily activities on their own. Copyright 2003 The New York Times Company

Keyword: Alzheimers
Link ID: 3570 - Posted: 03.18.2003

By CAROL KAESUK YOON For millenniums, bird species around the world have been put upon by cuckoos, duped into tending the eggs these sly birds slip into their nests and raising the chicks as their own. In response, some birds have evolved the ability to recognize cuckoo eggs, able to give even those that are quite convincing mimics of the host's eggs a good swift kick out of the nest. But scientists have long been puzzled by the fact that no birds seemed able to ferret out the cuckoo chick once it had hatched, always treating it as if it were their own, even when the cuckoo babies were the most obvious pretenders — great awkward things, differently colored and shaped from everyone else in the nest, sometimes six times the size of their tiny adoptive parents, towering over them while begging for food. Now, in the current issue of the journal Nature, researchers report finding that at least one bird, a dazzling creature aptly named the superb fairy-wren, has evolved the ability to recognize the cuckoo chick for what it is. Copyright 2003 The New York Times Company

Keyword: Evolution; Sexual Behavior
Link ID: 3569 - Posted: 06.24.2010

Jane Elliott, BBC News Online Health Staff Like many teenage boys Michael is a sports fanatic. He's passionate about his team Everton and loves playing squash. But unlike most other football fans Michael, aged 19, can't actually see and recognise the players properly. Ten years ago he was involved in a serious car smash and now sufferers from a disorder of the brain's visual processing system called visual agnosia. He has lost the normal long-term "memory banks" used to recognise visual information. Michael can see moving objects, colours and shapes, but needs other prompts such as voices to give him the complete picture to recognise people by. Dr Ros McCarthy, a neuropsychologist at Cambridge University, said Michael and other people with visual agnosia often found it difficult to recognise even very familiar faces. "They may not even recognise the faces of their wives or parents. (C) BBC

Keyword: Vision
Link ID: 3568 - Posted: 03.17.2003

Autopsy of inflamed brain points to vaccine dangers. ERICA CHECK An experimental vaccine against Alzheimer's disease may work, but causes life-threatening side effects in some cases, the autopsy of a participant in the vaccine's trial confirms. Elan, the pharmaceutical company developing the vaccine, is keen to highlight the treatment's potential benefits. But the findings leave its future in serious doubt. The vaccine is thought to work by turning the body's immune system against brain abnormalities known as plaques that are associated with Alzheimer's. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Alzheimers
Link ID: 3567 - Posted: 06.24.2010

HANOVER, NH – A Dartmouth research group has found a new and unexpected way our attention can be grabbed – by grabbable objects. Their study, which appears in the March 17 advance online issue of Nature Neuroscience, demonstrates that objects we typically associate with grasping, such as screwdrivers, forks or pens, automatically attract our visual attention, especially if these items are on a person's right-hand side. In the brain, there are two primary visual pathways, one for identifying objects (perception) and one to guide your arms and legs based on what you see (action). To better understand how these two systems may interact, the Dartmouth team studied whether visual perception, specifically peripheral visual attention, influences motor systems in the brain. "People have studied peripheral vision and how it helps perception, but nobody really talked about it in terms of helping action," says Todd C. Handy, the lead author and a research assistant professor at the Center for Cognitive Neuroscience at Dartmouth. "There are certain things that we all know attract our attention, like flashing lights and loud noises. Yet, think about how often we grab things without directly looking at them. Now here's evidence that, to help us do this, grabbable objects can literally grab our attention. There's a clear association."

Keyword: Vision; Attention
Link ID: 3566 - Posted: 06.24.2010

Taking just one ecstasy tablet is enough to make you depressed, a study suggests. Researchers at London Metropolitan University have found that people who take ecstasy are more likely to suffer depression compared to non-users and even people who use other drugs. Their study also indicates that heavy users of the drug are at risk of becoming clinically depressed. The researchers believe ecstasy has a long-lasting impact on key chemicals in the brain, which regulate mood. The findings are based on a study of almost 600 working professionals. They each filled out a form detailing previous drug use and overall mood. The researchers split these people into three different groups - those who had only taken ecstasy; those who took other drugs; and those who have never taken drugs. (C) BBC

Keyword: Drug Abuse; Depression
Link ID: 3565 - Posted: 03.16.2003

By GRETCHEN REYNOLDS Wendell Johnson was a tall, knobby 20-year-old farm boy when he arrived at the University of Iowa in Iowa City to study English in 1926. The class president and valedictorian of his tiny high school in Roxbury, Kan., Johnson was engaging, ''quite a clown'' in the estimation of the folks back home. He also stuttered grotesquely, often rendered speechless by the impediment. His inability to express himself nudged him toward writing and literature, and he developed a penchant for antic humor, which kept him popular despite his silence. It also propelled him to U. Iowa, the most famous center for stuttering research in the world. Around the country, speech pathology was fighting to be recognized as a science, and Iowa was the new discipline's polestar. Dozens of experiments were under way when Johnson arrived, and he enthusiastically threw himself into the invigorating work, switching to psychology for his master's study. ''I became a speech pathologist because I needed one,'' he'd later say. Many of his fellow graduate students stuttered almost as painfully as he did, and they'd use one another as guinea pigs. They'd draw blood, hook themselves to electrodes, strike their knees to test reflexes, whip out notebooks in midstride and transcribe their own and others' faltering speech. They'd administer electroshock and shoot guns off near each other's ears to see if being startled affected stuttering. (It didn't, although the same experiment performed on normal speakers did affect their speech.) They'd also put casts on one another's arms, since it was hoped that immobilizing a person's dominant hand somehow would untangle confused brain signals. At one point, about 30 stutterers, including Johnson, wandered the Iowa campus with their arms wrapped in plaster, sometimes playing wrong-handed badminton. ''We knew that we were working on something central in the life of a human being,'' one of Johnson's contemporaries told an Iowa historian. ''We weren't just puttering around on the fringes.'' At the time, physiology had become the favored explanation at Iowa for stuttering. The department's lead professors were certain that the disorder originated in misdirected brain signals. They had used a new device called an electromyograph to study neuromus-cular activity in stutterers, nonstutterers and, in one experiment, people who were drunk (students who, solely in the interests of science, had become soused; the researchers skirted Prohibition by requisitioning alcohol from the university hospital.) The readouts from the booze-tinged subjects showed, to no one's surprise, impair-ment. Intriguingly, more comprehensive experiments showed that stutterers had subtle neuromuscular responses different from those of their nonstuttering peers. Copyright 2003 The New York Times Company

Keyword: Language; Development of the Brain
Link ID: 3564 - Posted: 03.16.2003

By RICHARD PÉREZ-PEÑA In state capitols, universities, charitable foundations, hospitals and companies around the country, a scattershot movement is under way to counteract President Bush's 2001 order sharply limiting federal money for embryonic stem cell research. Lawmakers in New York, Maryland, Rhode Island, Tennessee, Washington and Massachusetts are considering bills authorizing embryonic stem cell research, according to advocates of the research and the National Conference of State Legislatures. Some bills go further, as one passed in California did last year when it authorized the use of state money to support research using embryonic stem cells, which scientists contend could eventually yield treatments for diabetes, Parkinson's, Alzheimer's, heart disease, cancer and other ailments. Mr. Bush and others who oppose such research say it is immoral because human embryos are destroyed when the cells are extracted. Copyright 2003 The New York Times Company

Keyword: Stem Cells
Link ID: 3563 - Posted: 03.16.2003

Anti-depressant may help treat Alzheimer's disease. HELEN R. PILCHER Lithium, the standard drug for manic depression, might also help to treat other brain conditions such as stroke and Alzheimer's disease, new research suggests1. The simple salt stimulates stem cells growing in a dish to multiply faster, hinting that it could prompt stem cells in the brain to produce new cells to replace those damaged by disease. "We have underestimated the effects of lithium," says De-Maw Chuang of the Mood and Anxiety Disorder Program at the National Institutes of Health in Bethesda, Maryland. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Depression; Stem Cells
Link ID: 3562 - Posted: 06.24.2010

There is little truth in the widely held idea that pregnancy reduces a woman's mental firepower, research has found. Many people - including some midwives - believe that pregnancy has a damaging impact on memory and concentration. A team of psychologists from the University of Sunderland asked pregnant women for their views - and found that many subscribed to the popular view. But when the same women performed a series of mental tests they actually performed no worse than women who were not carrying a child. The researchers, led by Dr Ros Crawley, compared the performance of 15 pregnant women an 14 who were not. They conducted tests twice during pregnancy and at six months and 12 months after birth. (C) BBC

Keyword: Hormones & Behavior; Learning & Memory
Link ID: 3561 - Posted: 03.15.2003