ANN ARBOR, Mich.---Positive emotions like joy and humor help people "get the big picture," virtually eliminating the own-race bias that makes many people think members of other races "all look alike," according to new University of Michigan research. "Negative emotions create a tunnel vision," said U-M psychology researcher Kareem Johnson. "Negative emotions like fear or anger are useful for short-term survival when there's an immediate danger like being chased by a dangerous animal. Positive emotions like joy and happiness are for long-term survival and promote big picture thinking, make you more inclusive and notice more details, make you think in terms of 'us' instead of 'them.'" To simulate getting a quick glance of a stranger, scientists flashed photos of individuals for about a half second, finding subjects recognized members of their own race 75 percent of the time but only recognized members of another race 65 percent of the time, Johnson said. However, researchers found positive emotions boosted that recognition of cross-race faces about 10 to 20 percent, eliminating the gap. The findings will appear in an upcoming issue of the journal Psychological Science. Johnson, who is completing his PhD work in psychology, and Barbara Fredrickson, a U-M psychology professor and director of the Positive Emotion and Psychophysiology Laboratory, specialize in the power of positive emotions.

Keyword: Emotions
Link ID: 6793 - Posted: 02.02.2005

PITTSBURGH, – Puberty, that awkward phase when boys and girls are primed for their sexual reproductive years as men and women, appears to be triggered by the brain's own version of "It takes two to tango," whereby a signal literally gets turned on by a molecule that is produced by a gene aptly named KiSS-1. The couple – a biochemical equivalent to Adam and Eve – makes its sudden appearance in a region of the brain called the hypothalamus just as puberty begins, according to a study published in this week's online edition of the Proceedings of the National Academy of Sciences (PNAS). Until now, little had been known about what instigates the cascade of hormone secretions that, over time, produces puberty's tell-tale physical changes, including the development of breasts in girls and voice change in boys. As such, this research begins to answer one of the most vexing questions about human development: What causes puberty to begin? How is it that the full repertoire of reproductive hormones can exist at birth, go into hiding at about four to six months of age, then reemerge in full force some 10 to 12 years later? "Puberty is critical to human development. And while there is a fairly good understanding of how the endocrine system regulates the hormones involved, just how and when the brain activates this process has been a great mystery. An appreciation of puberty's deep-seated neurobiological mechanisms could, for instance, help prevent precocious or delayed puberty from occurring in some children," noted the study's lead author, Tony Plant, Ph.D., a professor in the departments of cell biology and physiology and obstetrics, gynecology and reproductive sciences, as well as director of the Center for Research in Reproductive Physiology at the University of Pittsburgh School of Medicine.

Keyword: Development of the Brain; Hormones & Behavior
Link ID: 6792 - Posted: 06.24.2010

Durham, N.C. – A gene that plays many fundamental roles in cells throughout the body has, for the first time, been implicated in human disease, according to researchers at the Duke Center for Human Genetics. A defect in the ubiquitous gene dynamin 2 underlies one form of the prevalent, familial nerve disorder, known as Charcot-Marie-Tooth disease (CMT). The disorder affects approximately 1 in every 2,500 people, making it one of the most common of all hereditary disorders, said the researchers. Their findings also reveal a previously unknown link between CMT and a deficiency of white blood cells, suggesting that defects in dynamin 2 might underlie both conditions, the researchers reported in the Jan. 30, 2005, issue of Nature Genetics. The discovery -- together with earlier findings of genes that can also cause the genetically heterogeneous and debilitating disease -- is providing new insight into the nervous system, said first author of the study Stephan Züchner, M.D., assistant professor of psychiatry and member of the Duke Center for Human Genetics. Also, he said, the findings bring a better understanding of the types of defects that might, in general, lead to peripheral nerve disorders. © 2001-2005 Duke University Medical Center

Keyword: Genes & Behavior
Link ID: 6791 - Posted: 06.24.2010

DALLAS – Researchers at UT Southwestern Medical Center have discovered that drugs commonly used to treat psychiatric illnesses and blood disorders in humans may protect the brain cells that die in people with Huntington's disease, possibly delaying the onset and slowing the progression of the disease. These findings, available online and in today's issue of Proceedings of the National Academy of Sciences, may offer new treatment options for Huntington's disease, which has no cure. Huntington's disease is a neurological disorder in which the medium spiny striatal neurons, the nerve cells that control movement and certain mental functions die. Patients die within 10-15 years after onset of the disease. The disease is caused by a mutation in the gene that makes the protein huntingtin. The mutation creates a long chain of the amino acid glutamine at one end of the protein. The length of the chain directly correlates with age of onset of the disease, with longer chains leading to symptoms earlier in life. In previous studies, Dr. Ilya Bezprozvanny, associate professor of physiology at UT Southwestern, established that one of the defects that leads to death of nerve cells with the mutant huntingtin protein is improper regulation of calcium due to errant signals in the cells. Calcium is inappropriately released from its storage area in the cells, and eventually the cells die.

Keyword: Huntingtons; Apoptosis
Link ID: 6790 - Posted: 06.24.2010

You're much more likely to dream about fighting with your spouse, or other aggressive interactions, during REM sleep than non-REM sleep, according to a new study. This specialization of dream states gives further credence to the theory that dreams are more than just meaningless, chaotic images. While we dream, the brain cycles through REM and non-REM sleep stages at 90-minute intervals. Dreams during both stages tend to mull over social interactions, leading some sleep researchers to speculate that dreams may help people better deal with these encounters. Researchers have also known that REM and non-REM sleep activate different areas of the brain. REM sleep, for example, stimulates the amygdala, which handles fear and aggression, while non-REM sleep kindles the forebrain, which plays a role in impulse control and more cognitive functions. Cognitive neuroscientist Patrick McNamara of Boston University School of Medicine and colleagues wondered if these distinct activations resulted in different types of dreams. To investigate, the team collected dream and wake reports from 15 subjects over the course of 2 weeks. During the day, the researchers paged the subjects every 2 hours and instructed them to tape record their thoughts. At night, they did the same, but the subjects also wore a sleep monitoring system called "the nightcap" which differentiates between REM and non-REM sleep by counting head and eyelid movements. The researchers found that of the dreams that focused only on aggressive interactions, 21 occurred during REM sleep. Some aggression did show up in non-REM sleep, but in those dream arguments, the dreamer never initiated it. Copyright © 2005 by the American Association for the Advancement of Science.

Keyword: Sleep
Link ID: 6789 - Posted: 06.24.2010

Combining magnetic and gold nanoparticles with strands of DNA could allow the early detection of Alzheimer's disease. If successful, future treatments could then be used to prevent symptoms from ever appearing. Identifying and tracking Alzheimer's disease currently relies on brain imaging and psychological testing. A firm diagnosis can only be made by autopsy. But recent studies have revealed several biochemical markers that may provide the basis for a living diagnosis. These include tiny proteins called amyloid-beta-derived diffusible ligands (ADDLs), which exist at elevated levels in the brains of Alzheimer's patients. Dimitra Georganopoulou and her colleagues at Northwestern University in Chicago, Illinois, US, suspected ADDLs might also be present in the cerebrospinal fluid, which can be collected using a spinal tap. But the concentration of the proteins would be incredibly tiny, if they were there at all. So the team turned to a recently developed technique called bio-barcoding, shown to be thousands of times more sensitive for protein detection than conventional tests. "It's the only tool in town with the necessary sensitivity," says team member Chad Mirkin, whose lab developed the technique. © Copyright Reed Business Information Ltd.

Keyword: Alzheimers
Link ID: 6788 - Posted: 06.24.2010

Mark Peplow Animal rights activists who disrupt UK medical research could face up to five years in jail, if a legal amendment proposed by the British government becomes law. The new law would make it a criminal offence to cause "economic damage" to businesses connected with animal research, either by intimidating individuals or by interfering with commercial activities. "Animal rights extremism is out of control," says Simon Festing, head of the Research Defence Society, London, which lobbies for the use of animals in research. "It's time something was done about these zealots." Current legislation focuses on physical damage caused by protestors. But activists are increasingly trying to undermine animal-testing laboratories by targeting the companies that supply them, even threatening courier services who make deliveries to the high-security sites. "This new law would not affect the important right to peaceful protest, while cracking down hard on those extremists committing crimes, and some horrific acts, against innocent people involved in the supply chain," says the trade and industry secretary, Patricia Hewitt, who announced the amendment on 31 January. ©2005 Nature Publishing Group

Keyword: Animal Rights
Link ID: 6787 - Posted: 06.24.2010

Michael Hopkin New languages can develop consistent rules of grammar within a single generation of their birth, a study of an Israeli sign language has shown. The Al-Sayyid Bedouins, who live in Israel's Negev region, have a high rate of congenital deafness. In a population of about 3,500, roughly 150 people are deaf. The community, which was founded about 200 years ago, has developed its own sign language over the past 70 years, with no apparent outside influences. This is the first documented example of a language evolving from scratch in such isolation. Sentences in Al-Sayyid Bedouin sign language have a word order of 'subject, object, verb' (SOV), as in the phrase 'I apple give'. Israel's spoken languages, Arabic and Hebrew, use 'subject, verb, object' (SVO). The same goes for English, as in 'I give apple'. "We didn't expect to see word order so quickly, and didn't expect to see this particular word order," says Carol Padden of the University of California, San Diego, who led the study. The discovery suggests that grammar appears early in the development of face-to-face languages. Written language can take centuries to develop consistent grammar. ©2005 Nature Publishing Group

Keyword: Language
Link ID: 6786 - Posted: 06.24.2010

By Amanda Gardner (HealthDayNews) -- It took 29 internationally renowned scientists to get the ball rolling, but the term "birdbrain" could be on its way out, at least in its pejorative sense. "Birdbrain comes with two ideas: a small brain and also stupidity," said Erich Jarvis, an assistant professor of neuroscience at Duke University Medical Center, and one of the ringleaders of the group. "It just has to change." Perhaps more relevant to the scientific community, Jarvis and the 28 other scientists have renamed the terminology for avian brain structures to reflect recent scientific discoveries. Those discoveries show that birds are actually closer to mammals when it comes to brainpower. Their arguments are detailed in a paper appearing in the February issue of Nature Reviews Neuroscience. "The classic view is totally wrong," said Jarvis, who is also lead author of the paper. "I realized I couldn't publish papers with names that have wrong meanings attached to them. It is against my scientific conscience, and it is poor for scientific advance." © 2005 Forbes.com Inc.™

Keyword: Sexual Behavior; Language
Link ID: 6785 - Posted: 06.24.2010

By JIM YARDLEY NXI, China - For farming families in the lush mountains of coastal Fujian Province, the famous crop is oolong tea and the favorite source of labor is sons. The leafy bushes of tea fill the hillsides the same way young boys fill the village streets. There is such a glut of boys here - roughly 134 are born for every 100 girls - that the imbalance has forced an unlikely response from the Chinese government. To persuade more families to have girls, it has decided in some cases to pay families that already have daughters. The Communist Party is often vilified for its so-called one-child policy. The government credits the policy for sharply slowing China's population growth, but critics say it is a major reason many families now use prenatal scans and selective abortions to make certain that their child is a boy. Today, China has one of the world's worst cases of "missing" girls. Until recent years, the government largely ignored or denied the problem. Last March, President Hu Jintao declared it must be solved by 2010. Government officials now have declared that selective sex abortions will become a criminal offense. Such abortions were already banned, but doctors often accepted bribes from parents who wanted to guarantee a boy. Copyright 2005 The New York Times Company

Keyword: Sexual Behavior
Link ID: 6784 - Posted: 01.31.2005

The government says it will review all academic and clinical studies linking cannabis use to mental health problems. The Department of Health says it is now generally agreed among doctors that cannabis is an "important causal factor" in mental illness. It follows a mental health group's call for the government to investigate "the link between cannabis and psychosis". Rethink said its reclassification from a Class B to Class C drug sent a "confusing message" to young people. The charity wants the Commons Health Select Committee to launch an inquiry into the effect cannabis has on users. Its call was also backed by health campaign group Sane which wants the classification of cannabis to be reversed. A Department of Health spokesman said it was already commissioning a review. "We have no objection to the health select committee looking into this," he said. "However we are in the process of commissioning an expert review of all the academic and clinical evidence of the link between cannabis use and mental health, particularly schizophrenia. "There is medical clinical evidence now that there is an important causal factor between cannabis use and schizophrenia - not the only factor, but an important causal factor. That is the common consensus among the medical fraternity." Cannabis was reclassified last year so that police could target hard drugs. Home Office figures released on Friday showed that arrests for possession of cannabis fell by a third in the first year of its reclassification. However, Rethink said there had been a 60% increase in people who smoked drugs and had mental health problems in the last five years. Most medical experts agree that smoking cannabis in itself does not cause mental illness, but that people who are predisposed to psychosis are much more likely to develop symptoms if they use the drug regularly. (C)BBC

Keyword: Drug Abuse
Link ID: 6783 - Posted: 01.31.2005

Multiple genes - and not just the sex chromosomes - are important in sexual orientation, say US scientists. A University of Illinois team, which has screened the entire human genome, say there is no one 'gay' gene. Writing in the journal Human Genetics, they said environmental factors are also likely to be involved. The findings add to the debate over whether sexual orientation is a matter of choice. Campaigners say equality is the more important issue. Much of the past genetic research into male homosexuality had focused solely on the X chromosome, passed down to boys by their mother, according to lead researcher Dr Brian Mustanski. His team looked at all 22 pairs of non-sex chromosomes of 456 individuals from 146 families with two or more gay brothers. They found several identical stretches of DNA that were shared among gay siblings on chromosomes other than the female X. About 60% of these brothers shared identical DNA on three chromosomes - chromosome 7, 8 and 10. If it were down to chance, only 50% of these stretches would be shared, said the authors. The region found on chromosome 10 correlated with sexual orientation only when it was inherited from the mother. Dr Mustanski said the next step would be to see if the findings could be confirmed by further studies, and to identify the particular genes within the newly discovered sequences that are linked to sexual orientation. "Our study helps to establish that genes play an important role in determining whether a man is gay or heterosexual," he said, but added that other factors were also important. (C)BBC

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 6782 - Posted: 01.31.2005

A popular painkiller is being withdrawn from the UK market over concerns about links with suicide. Co-proxamol accounts for up to 400 deaths by accidental and intentional overdoses each year, it is estimated. The drug, used by thousands for conditions such as back pain, will be phased out over the next year or two. People do not need to come off the drug yet, and should discuss their treatment with their GP, said the Medicines and Healthcare products Regulatory Agency. A spokeswoman said their doctor would be able to discuss alternative treatments with them . Letters are being sent to GPs informing them of the decision. Data shows fatal overdoses due to co-proxamol are the second most frequent means of suicide with prescribed drugs in England and Wales. The risk of death associated with co-proxamol overdose seems to be higher than for either tricyclic antidepressants or paracetamol. The drug is a combination analgesic containing paracetamol and the opioid dextropropoxyphene. But co-proxamol is no better than full strength paracetamol at relieving pain and is known to be very toxic in overdose. For this reason, the Committee on Safety of Medicines, an independent expert body that advises the government on medicines, was asked to look at the risks and benefits of co-proxamol. (C)BBC

Keyword: Drug Abuse; Depression
Link ID: 6781 - Posted: 01.31.2005

MADISON - After years of trial and error, scientists have coaxed human embryonic stem cells to become spinal motor neurons, critical nervous system pathways that relay messages from the brain to the rest of the body. The new findings, reported online today (Jan. 30, 2005) in the journal Nature Biotechnology by scientists from the University of Wisconsin-Madison, are important because they provide critical guideposts for scientists trying to repair damaged or diseased nervous systems. Motor neurons transmit messages from the brain and spinal cord, dictating almost every movement in the body from the wiggling of a toe to the rolling of an eyeball. The new development could one day help victims of spinal-cord injuries, or pave the way for novel treatments of degenerative diseases such as amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease. With healthy cells grown in the lab, scientists could, in theory, replace dying motor neurons to restore function and alleviate the symptoms of disease or injury. Much sooner in the future, the advance will allow researchers to create motor neuron modeling systems to screen new drugs, says study leader Su-Chun Zhang, an assistant professor of anatomy and neurology in the Stem Cell Research Program at the Waisman Center at UW-Madison.

Keyword: ALS-Lou Gehrig's Disease ; Stem Cells
Link ID: 6780 - Posted: 01.31.2005

People who cannot sit still for more than a few minutes provide a clue to keeping slim and trim, a US study says. The Mayo Clinic team says some people have a biological need to fidget and, as a result, burn more calories. They used technology embedded in pants to log even the smallest movements of 10 obese and 10 lean volunteers. The team told Science Magazine that the calories people burned in everyday life were more important in determining weight than previously thought. While fidgeters burn off the calories, couch potatoes can pile on the pounds, they said. The technology was based on that used in fighter-jet control panels, and allowed the scientists to monitor body postures and movements every half-second, continuously for 10 days, from the volunteers' undergarments. The study participants were asked to go about their normal daily routines while wearing the undergarments for the first 10 days of the study. The Mayo team entered this data into a computer, along with the subjects' weights. For the second part of their experiment they asked 10 volunteers who were overweight and 10 who were lean to eat special diets. (C)BBC

Keyword: Obesity
Link ID: 6779 - Posted: 01.29.2005

By R. Douglas Fields In the movie thriller Memento, the principal character, Leonard, can remember everything that happened before his head injury on the night his wife was attacked, but anyone he meets or anything he has done since that fateful night simply vanishes. He has lost the ability to convert short-term memory into long-term memory. Leonard is driven to find his wife's killer and avenge her death, but trapped permanently in the present, he must resort to tattooing the clues of his investigation all over his body. That disturbing story was inspired by the real case history of a patient known in the medical literature only as "HM." When HM was nine years old, a head injury in a bicycle accident left him with debilitating epilepsy. To relieve his seizures that could not be controlled in any other way, surgeons removed parts of HM's hippocampus and adjoining brain regions. The operation succeeded in reducing the brain seizures but inadvertently severed the mysterious link between short-term and long-term memory. Information destined for what is known as declarative memory--people, places, events--must pass through the hippocampus before being recorded in the cerebral cortex. Thus, memories from long ago that were already stored in HM's brain remained clear, but all his experiences of the present soon faded into nothing. HM saw his doctor on a monthly basis, but at each visit it was as if the two had never met. © 1996-2005 Scientific American, Inc.

Keyword: Learning & Memory
Link ID: 6778 - Posted: 06.24.2010

Simply placing a cold cap on a baby's head may be enough to protect it from brain damage and possible death. So report researchers today in the first study to demonstrate an effective treatment for oxygen deprivation in newborns. Oxygen deprivation at birth is a serious matter. It can cause learning disabilities, cerebral palsy, or death in 0.1 to 0.2% of otherwise healthy full-term babies. To date, there has been no treatment available for this rare event, which results from abnormalities and complications during delivery. Pediatric and perinatal biologist Peter Gluckman, now at the Liggins Institute in Auckland, New Zealand, and colleagues first began investigating the problem 20 years ago. The team discovered that oxygen-deprived brain cells don't die immediately. The brain produces compounds that stop cell death, but it takes 2-3 days for the cells to accumulate sufficient levels. So the researchers hit on the idea of cooling the brain for 2-3 days to slow down the process of cell death and buy the brain time to heal itself. After testing the idea on sheep fetuses, the researchers developed a cooling cap for newborn babies. Cooled water is pumped through the cap, which lowers the baby's body temperature by 2-3 degrees Celsius for 3 days following birth. Copyright © 2005 by the American Association for the Advancement of Science.

Keyword: Development of the Brain; Apoptosis
Link ID: 6777 - Posted: 06.24.2010

Connecting brains to computers could circumvent disabilities Christen Brownlee At the University of Tübingen in Germany, neurobiologist Andrea Kübler works with a 49-year-old patient whom she identifies only as H.S. Like many of Kübler's patients, H.S. suffers from amyotrophic lateral sclerosis (ALS), a degenerative disease that slowly breaks down the nerve cells necessary for motion. The disease has paralyzed H.S., stripping him of the motor functions that most people take for granted: sitting up, eating, and even breathing. H.S. was diagnosed with ALS 14 years ago, and a permanent ventilator has done his breathing for him since 1993. From then until recently, H.S. could converse with Kübler and his caregivers only by blinking his eyes. Many people paralyzed by a variety of causes—strokes, tumors, or traumatic brain injuries, to name a few examples—communicate rather well by using their remaining, although impoverished, muscle power. For example, French editor Jean-Dominique Bauby, who was paralyzed by a stroke, dictated a 132-page novel (The Diving Bell and the Butterfly, 1997, Knopf) just by blinking his left eye. Similarly, decades after physicist Stephen Hawking was paralyzed by ALS, he continues to give world-renowned lectures by feeding words into a computer program with a flick of his finger. Eventually, H.S.'s paralysis might prevent him from even blinking his eyes to express himself. He'd then be in a state that doctors aptly refer to as "locked-in syndrome." Thousands of paralyzed people worldwide are in that socially closed-off state. Copyright ©2005 Science Service

Keyword: Robotics
Link ID: 6776 - Posted: 06.24.2010

Christen Brownlee While it hasn't yet been caught in the act, a single-celled parasite has been ready for sex for billions of years. A new research finding provides evidence that sexual reproduction started as soon as life forms that have nuclei and organelles within their cells branched off from their structurally simpler ancestors. The parasite Giardia intestinalis is well known for causing a diarrheal disease that animals and people contract after drinking contaminated water. Many researchers consider this species to be one of the most ancient living members of the eukaryote, or true nucleus, lineage. However, unlike most eukaryotes, G. intestinalis and its relatives have been long considered to reproduce only asexually—by division into two identical cells. To determine when reproduction via sperm and eggs originated, John Logsdon of the University of Iowa in Iowa City and his colleagues took a close look at G. intestinalis' mysterious reproductive life. They focused on the hallmark of sexual reproduction known as meiosis, the process that halves the number of an organism's chromosomes to make gametes such as sperm and eggs. Among available data on the G. intestinalis genome, the researchers searched for genes similar to those that control meiosis in other eukaryotes, including plants, animals, and fungi. Copyright ©2005 Science Service.

Keyword: Sexual Behavior; Evolution
Link ID: 6775 - Posted: 06.24.2010

Scientists say they have discovered the exact mechanism behind the death of brain cells following a stroke. The main culprit is an overload of charged calcium particles or ions, they told the journal Cell. As the brain is starved of oxygen by reduced blood flow, events occur that cause dangerously high levels of calcium ions within the brain cells. The Medical Research Council team believes correcting the calcium imbalance could help treat strokes. Scientists have suspected for some time that calcium was the culprit. But research had mainly concentrated on trying to block the entry of calcium ions into dying nerve cells. The latest study suggests that the main problem is actually a fault in the mechanism that removes calcium ions from the nerve cells. Professor Pierluigi Nicotera and colleagues at the MRC's toxicology unit in Leicester looked at what was happening in the brains of rats when these animals suffered a stroke. When the blood flow to the brain was abruptly stopped, as occurs with a stroke, the nerve cells deprived of oxygen released chemicals that they use to communicate with each other. One of these, called glutamate, causes more widespread damage by triggering a flood of calcium ions into the affected and neighbouring nerve cells. (C)BBC

Keyword: Stroke
Link ID: 6774 - Posted: 01.28.2005