By L. L. DESAUTELS Not long ago, I made a decision that up until that time was unthinkable: give up driving a car the traditional way. Multiple sclerosis has numbed my feet to the point where I can no longer tell without looking whether they are on the pedals, and my hip flexors are so weakened that naturally lifting my leg from gas to brake and back again is impossible. For 25 years, driving had always been an enormous pleasure and privilege, and it was now fast becoming riddled with uncertainty, and potentially unsafe. For many of us, driving, like countless other tasks we take for granted, is associated with personal freedom and a sense of control. What a thrill to be on the open road, windows down and your favorite song on the radio! Copyright 2003 The New York Times Company

Keyword: Multiple Sclerosis
Link ID: 3936 - Posted: 06.20.2003

Night owls and early birds owe differences to clock-gene length. MICHAEL HOPKIN Whether you are a morning or an evening person could depend on a single gene, a study of extreme sleeping habits has revealed. Understanding the body clock's genetic basis may help people to make the most of their day. Night owls and early birds tend to carry different versions of a gene called Per3, says Simon Archer of the University of Surrey in Guildford, UK. This difference may make their preferred sleep cycles longer or shorter than 24 hours. The brain uses the cycle of light and dark to align its clock with the Earth's 24-hour cycle. "Every day we reset our clocks slightly," says Archer. People whose natural cycles are much shorter or longer than 24 hours often find themselves wakeful or sleepy at odd times. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Sleep; Genes & Behavior
Link ID: 3935 - Posted: 06.24.2010

Blue-throated lizards that help each other achieve reproductive success are also helping scientists understand how social cooperation evolved. SANTA CRUZ, CA--Blue-throated lizards that help each other achieve reproductive success are also helping scientists understand how social cooperation evolved. Most examples of cooperative behavior in animals involve cooperation between genetically related individuals, which is explained by the theory of "kin selection." Now, researchers have described an example of cooperation between genetically similar but unrelated members of a lizard species common in the western United States. Their findings, published in the June 20 issue of the journal Science, shed new light on the evolution of cooperation and social behavior. Barry Sinervo, a professor of ecology and evolutionary biology at the University of California, Santa Cruz, has been studying the side-blotched lizard (Uta stansburiana) since 1989. He recently teamed up with French ecologist Jean Clobert to analyze ten years worth of data from Sinervo's ongoing field studies. The two scientists are coauthors of the new paper in Science.

Keyword: Evolution; Sexual Behavior
Link ID: 3934 - Posted: 06.20.2003

MGH imaging study finds differences in brain area responsible for vigilance A key area in the brains of people who displayed an inhibited temperament as toddlers shows a greater response to new faces than does the same brain area in adults who were uninhibited early in life, according to a study by researchers from Massachusetts General Hospital (MGH). The imaging studies of the amygdala – a part of the brain that responds to events requiring extra vigilance – appear in the June 20 issue of Science. "Our findings both support the theory that differences in temperament are related to differences in amygdala function, something earlier technology could not prove, and show that the footprint of temperamental differences observed when people are younger persist and can be measured when they get older," says Carl Schwartz, MD, director of the developmental psychopathology lab in the MGH Psychiatric Neuroscience Program, the paper's first author. "In a way, this research is the neuroscientist's version of the 'Seven-Up' movies," he adds, referring to a well-known series of British documentaries that have revisited a group of people every seven years for more than 40 years. In psychological terms, temperament refers to a stable emotional and behavioral profile that is observed in infancy and partially controlled by genetic factors. One of the most carefully studied temperamental measures relates to a child's typical response to unfamiliar people, objects and situations. It usually is described with terms such as shyness versus sociability, caution versus boldness, or withdrawal versus approach. The two extremes of this measurement define types of children called inhibited and uninhibited by Jerome Kagan, PhD, professor of Psychology at Harvard University, a co-author of the current study.

Keyword: Emotions
Link ID: 3933 - Posted: 06.24.2010

Are you a lark or an owl? Are you at your best early in the morning or late at night? Whatever the answer, scientists believe they may now know why some of us are early risers while others prefer to burn the midnight oil. The answer appears to lie in our genes. Researchers at the University of Surrey say they have found a link between people's preference for mornings or evenings and a gene called Period 3. This gene is one of those involved in regulating the body's internal clock. It comes in two forms - a shorter and longer one. Researchers have found that people with an extreme preference for early mornings are more likely to have a long version of Period 3. In contrast, those with an extreme preference for evenings are more likely to have the shorter version. (C) BBC

Keyword: Genes & Behavior; Sleep
Link ID: 3932 - Posted: 06.19.2003

Exclusive from New Scientist Print Edition A study of mercury levels in the baby hair of children who were later diagnosed with autism has produced startling results. The babies had far lower levels of mercury in their hair than other infants, leading to speculation that autistic children either do not absorb mercury or, more likely, cannot excrete it. The results will be seized upon by parents who blame vaccines containing the mercury-based preservative thimerosal for their children's autism, some of whom are suing health authorities in the US and Canada. (The MMR vaccine that some accuse of triggering autism, despite a lack of credible evidence, does not contain mercury.) But while the study's findings support the theory that some children have a genetic fault that makes them far more susceptible to mercury poisoning, the results certainly do not prove this, or that thimerosal is involved. © Copyright Reed Business Information Ltd.

Keyword: Autism
Link ID: 3931 - Posted: 06.24.2010

By Danny Kingsley, ABC Science Online — Forget about using those expensive sprays to try and attract the opposite sex — humans don't have the ability to detect pheromones, and American research concludes it is due to our color vision. The research, undertaken by Assistant Professor Jianzhi Zhang from the University of Michigan, involved a comparison of the genes of primates that can see color and those that can't. It seems that males developing color vision negated the need for pheromones to attract mates. Pheromones are water-soluble chemicals released by an individual as a signal to others of the same species. They are used for social and reproductive behavior and in land-based animals they are mainly sensed by an organ called the vomeronasal organ (VNO). But humans and other primates only have remnant VNOs, so they have no or very little ability to detect pheromones. Copyright © 2003 Discovery Communications Inc.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 3930 - Posted: 06.24.2010

-- A protein that plays a role in muscular dystrophies also may be involved in peripheral neuropathy - disorders of the nerves that carry messages between the brain and the rest of the body. The findings, by University of Iowa researchers and colleagues, may shed light on the causes and mechanisms of human peripheral neuropathies, which cause pain, numbness and muscle wasting. Peripheral neuropathies can be acquired as a result of diseases including diabetes and Hansen's disease (leprosy) or can be inherited. Some congenital peripheral neuropathies (those present at birth) can cause limb deformities. The UI study may suggest new treatment strategies for these conditions. In the peripheral nervous system, dystroglycan is found in Schwann cells, which wrap themselves around peripheral axons (nerve fibers) and protect them by producing a myelin sheath. The sheath allows nerve impulses to move faster and more efficiently along the nerves. If nerve fibers are the body's electrical wiring, then the myelin sheath represents the insulation. Copyright © 1992-2003 Bio Online, Inc.

Keyword: Muscles; Glia
Link ID: 3929 - Posted: 06.24.2010

Underwater echolocation has built-in dimmer switch. MICHAEL HOPKIN Dolphins adjust the volume of their sonar to target prey, a study has shown1. The system is perfectly tuned to home in on their preferred victims - schools of small fish. A dolphin's clicks quieten as it approaches its target, find Whitlow Au and Kelly Benoit-Bird of the University of Hawaii in Kailua. This isn't a stealth tactic, the researchers say. It seems to result from the way dolphins' nasal system produces sound - they make strings of clicks by expelling pressurized air from their blowholes. The mammals wait until one click bounces back before releasing another, Au and Benoit-Bird explain. As they draw nearer their prey, the echoes arrive sooner, so the click rate is correspondingly faster. "The rate increases as a dolphin closes in on its target," Au says. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Hearing
Link ID: 3928 - Posted: 06.24.2010

By MARY DUENWALD More than half of the Americans who suffer from depression now seek treatment, up from one-third 10 years ago, a new survey says. Yet nearly 60 percent of the people in treatment do not receive adequate care, the researchers found. More than 16 percent of Americans — as many as 35 million people — suffer from depression severe enough to warrant treatment at some time in their lives, according to the National Comorbidity Study, sponsored by the National Institutes of Health and published today in a special issue on depression of The Journal of the American Medical Association. In any given one-year period, 13 million to 14 million people, about 6.6 percent of the nation, experience the illness. The numbers are similar to those found in the first survey 10 years ago. At that time, the lifetime prevalence of depression was measured at nearly 15 percent and the one-year figure at 8.6 percent. Copyright 2003 The New York Times Company

Keyword: Depression
Link ID: 3927 - Posted: 06.24.2010

By SANDRA BLAKESLEE People are efficient, rational beings who tirelessly act in their own self-interest. They make financial decisions based on reason, not emotion. And naturally, most save money for that proverbial rainy day. Right? Well, no. In making financial decisions, people are regularly influenced by gut feelings and intuitions. They cooperate with total strangers, gamble away the family paycheck and squander their savings on investments touted by known liars. Such human frailties may seem far too complicated and unpredictable to fold into economic equations. But now many neuroscientists are beginning to argue that it is time to create a new field of study, called neuroeconomics. Copyright 2003 The New York Times Company

Keyword: Brain imaging; Emotions
Link ID: 3926 - Posted: 06.19.2003

By JENNIFER 8. LEE WASHINGTON, — Scientists from the Environmental Protection Agency say there is "sufficient evidence" to conclude that the country's most widely used pesticide, atrazine, causes sexual abnormality in frogs. They are recommending that the agency conduct more research to understand atrazine's mechanisms and its broader impact on frog populations. The scientists noted that there had been six studies involving three species of frogs that show a variety of defects, including frogs with both multiple testes and multiple ovaries, when exposed to the chemical. The scientists cautioned that the results from studies of atrazine had not been consistent and that it was not clear at what levels of exposure those effects occurred or how different frog species were affected. Copyright 2003 The New York Times Company

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 3925 - Posted: 06.24.2010

By NICHOLAS WADE Biologists have made a fundamental discovery about how the human Y chromosome, a genetic package inherited by men, protects itself against evolutionary decay. As part of the work, the scientists have tallied the exact number of genes on the Y chromosome, finding more than they had expected. That and other research has led the researchers to assess the genetic differences between men and women as being considerably greater than thought. Although most men are unaware of the peril, the Y chromosome has been shedding genes furiously over the course of evolutionary time, and it is now a fraction the size of its partner, the X chromosome. Sex in humans is determined by the fact that men have an X and a Y chromosome in each of their body's cells. Women have a pair of X's. Copyright 2003 The New York Times Company

Keyword: Sexual Behavior
Link ID: 3924 - Posted: 06.19.2003

STANFORD, Calif. - Nearly 5 million people in the United States suffer from schizophrenia or manic depression, making antipsychotics the fourth-highest selling class of drugs. But how effectively do the most commonly prescribed medications treat the disorder? And how much better are newer antipsychotics, known as atypicals, compared to their older counterparts? Ira D. Glick, MD, tackled these questions in a sweeping review of medical literature. Glick, professor of psychiatry and behavioral sciences at the Stanford School of Medicine, said 90 percent of antipsychotic prescriptions written in the United States are for atypicals. He and his colleagues found that their effectiveness, widely considered to be superior over conventional medications, varies from drug to drug. The researchers also found that four of the 10 studied atypicals were more effective than the older ones. "Some people consider the new antipsychotics a homogenous group, but there are differences," said Glick, senior author of a paper in the June issue of Archives of General Psychiatry. "Some of the drugs are clearly more effective and have fewer side effects than older medications."

Keyword: Schizophrenia
Link ID: 3923 - Posted: 06.19.2003

Researchers at the University of Illinois at Chicago are studying subtle abnormalities in eye movements that may one day be used to diagnose psychiatric disease. Irregularities in how the eyes track a moving object reflect defects in the neural circuitry of the brain and appear to correspond with particular types of mental disorders. Schizophrenic patients, for example, have difficulty keeping their eyes focused on slow-moving objects. With new technology, these abnormalities can be measured precisely and compared with normal patterns. "Psychiatric illnesses are not well understood neurologically," said John Sweeney, director of the Center for Cognitive Medicine in UIC's department of psychiatry. "Eye movement tests offer a way to investigate abnormalities in the brain that are causing these disturbances." The goal, Sweeney said, is to develop eye movement tests as a simple, noninvasive tool for diagnosing brain disorders, including schizophrenia, depression and developmental illnesses such as autism. "At present, however, the field is still in its infancy," he said.

Keyword: Schizophrenia
Link ID: 3922 - Posted: 06.19.2003

A medication used to treat the symptoms of mild-to-moderate Alzheimer disease may actually do more - it may be able to delay progression of the disorder, according to a study conducted at the Indiana University School of Medicine. The study, which appears in the June issue of Archives of Neurology, enabled researchers to evaluate a change in cognition observed in patients who prematurely discontinued treatment with placebo or Exelon ® (rivastigmine tartrate), a medication prescribed for many patients. "If Exelon only had an effect on the symptoms of the disease, we would have expected rapid deterioration in patients' cognition to the level observed in the placebo group after treatment withdrawal, but that was not the case with this study," notes Martin Farlow, M.D., professor of medicine at the IU School of Medicine and director of the Alzheimer Clinic at Indiana University Hospital.

Keyword: Alzheimers
Link ID: 3921 - Posted: 06.19.2003

New Haven, Conn. -- Adolescents are more vulnerable than any other age group to developing nicotine, alcohol and other drug addictions because the regions of the brain that govern impulse and motivation are not yet fully formed, Yale researchers have found. After conducting an analysis of more than 140 research studies from across the basic and clinical neurosciences, including many conducted at Yale, the researchers concluded that substance use disorders in fact constitute neurodevelopmental disorders. "Several lines of evidence suggest that sociocultural aspects particular to adolescent life alone do not fully account for greater drug intake," said Andrew Chambers, M.D., assistant professor of psychiatry at Yale School of Medicine and lead author of the study published this month in the American Journal of Psychiatry. "And while we strongly suspect that genetic factors in individuals can lower the threshold of drug exposure required for 'tripping the switch' from experimental to addictive drug use, here we have a phenomena where a neurodevelopmental stage common to virtually everyone regardless of genetic make-up confers enhanced neurobiological vulnerability to addiction."

Keyword: Drug Abuse; Development of the Brain
Link ID: 3920 - Posted: 06.19.2003

Why do some of us find it hard to control our diet or exercise? Neuroscientists writing in this month’s journal Nature Medicine say the reason could be all in our head. As this ScienCentral News video reports, the findings throw new light on a major epidemic in this country—obesity. How do you know when you’ve eaten enough and it’s time to work it off? Your brain tells you. Neuroscientists are now investigating whether some people overeat because of an imbalance in this brain mechanism. When we eat, nutrients in the food stimulate the secretion of the hormones leptin and insulin, which send signals to a part of the brain called the hypothalamus. When we eat too much, “the hormones working through the brain decrease the food intake, increase our energy expenditure, and even decrease the production of nutrients by other organs in the body,” explains Dr. Luciano Rossetti, professor of medicine and molecular pharmacology and director of the Diabetes Research and Training Center at the Albert Einstein College of Medicine. © ScienCentral, 2000-2003.

Keyword: Obesity
Link ID: 3919 - Posted: 06.24.2010

By RICHARD M. COHEN The sharp pain in my right knee has shot me over the falls. I have a new respect for the camel that invented the cumulative burden. Pain associated with multiple sclerosis — the upper back jolts in cervical disks, joint pain and endless muscle knots and spasms — are a part of life, filed away under "Routine." Grinding intestinal pain has receded to the muted timpani of the dull ache, a few years into post-colon-cancer, after-the-ileostomyitis. The grimace is fixed, built onto my face. Copyright 2003 The New York Times Company

Keyword: Pain & Touch
Link ID: 3918 - Posted: 06.24.2010

Junior coral-reef fish navigate using sound. JOHN WHITFIELD Trying to find Nemo? Follow your ears. That's what young fish do to relocate their home reefs. UK researchers have found that the hubbub of adult fish guides fry in the deep ocean. The discovery could help conservation. Recorded reef racket might attract youngsters to overfished or artificial reefs or to marine reserves. It also suggests that man-made noise may be confusing fish and damaging reef ecosystems. "Boat engines and power plants could be contributing to reductions in recruitment to reefs," comments fish biologist Su Sponaugle of the University of Miami. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Hearing; Animal Migration
Link ID: 3917 - Posted: 06.24.2010