By Rick Weiss Oh, the light! The autumn light! Is there anything more glorious than an October day, awash in the sun's low-slung amber rays? And yet . . . perhaps you feel the dread, too. The looming inkiness that, like the tide, crawls up your legs a little higher each day, turning that honeyed light to molasses and molasses to muck until you realize, too late, that the birds have left and the world has gone dark. Dark when you wake up, dark when you go home. In simpler times we slept more in winter, but modern living denies us that luxury. So increasingly each day, soft-white lights from yonder windows break -- along with halogens, tungstens and compact fluorescents. And when we can't stand it anymore, we resort to manipulation, declaring that 6 in the morning is now 5. You got a problem with that, take it up in the spring. Now science is finding that our manhandling of light and time is making us sick. Artificial illumination is fooling the body's biological clock into releasing key wakefulness hormones at the wrong times, contributing to seasonal fatigue and depression. And daylight saving time, extended by Congress this year for an extra four weeks, risks dragging even more Americans into a winter funk. Much more than mental health is at stake. Women who work at night, out of sync with the light, have recently been shown to have higher rates of breast cancer -- so much so that an arm of the World Health Organization will announce in December that it is classifying shift work as a "probable carcinogen." © 2007 The Washington Post Company

Keyword: Biological Rhythms
Link ID: 10902 - Posted: 06.24.2010

Until recently, only one of the approximately 30,000 genes in the human genome has been linked to risk of late-onset Alzheimer's disease (AD). Now, a new NIH-supported study in the Nov. 19, 2007, issue of NeuroReport (now online) used a publicly shared genome dataset to strongly support findings that variation in the sequence of the SORL1 gene may be a second risk factor gene for late-onset disease. Identifying the genes involved in AD ultimately may help determine who may be at greater risk and enable researchers to zero in on pathways to develop new treatments. The National Institute on Aging (NIA), part of the National Institutes of Health (NIH), funded the study, along with the Canadian Institutes of Health Research and a number of private foundations in the U.S., Canada and Japan. Three mutated genes — amyloid precursor protein (APP) and the presenilins (PS1 and PS2) — have been shown to cause rare, early-onset, familial forms of the disease which mostly occur in middle age. A gene variant — apolipoprotein ĺ4 (APO-ĺ4) — was the first confirmed risk factor for the common form of late-onset AD, which typically occurs after age 65. Earlier this year, researchers first linked variations in the gene SORL1 to late-onset AD. The analysis involved 14 collaborating institutions in North America, Europe and Asia, and 6,600 people who donated blood and tissue for genetic typing. To learn more, go to http://www.nia.nih.gov/NewsAndEvents/PressReleases/PR20070114SORL1gene.htm.

Keyword: Alzheimers; Genes & Behavior
Link ID: 10901 - Posted: 06.24.2010

By Nikhil Swaminathan If you watched football or the final game of the World Series yesterday, you may have noticed the following: When the announcers were speaking on camera, it seemed as though the sound of their voices were coming from their mouths. But when the commentary occurred off-screen as the game action was shown, it was quite apparent the TV speakers were the actual sound source of the endless color-commentary babble. This processing phenomenon in which a visual cue affects how one perceives an auditory stimulus—ventriloquism is another example—may be explained by new research that pinpointed neurons in a primitive brain area that responds to both visual and auditory information. This area, the inferior colliculus region in the midbrain, less than half an inch in diameter, is a way station for nearly all auditory signals as they travel from the ear to the cortex (the brain's central processing area). "It's important if you're going to be integrating visual and auditory information that they be on a level playing field, so both are encoded the same way," says Jennifer Groh, an associate professor at Duke University's Center for Cognitive Neuroscience and a co-author of the new work published in Proceedings of the National Academy of Sciences USA. "It's important for the auditory pathway to know where the eye is pointed." Groh and her colleagues planted electrodes in the brains of three monkeys, targeting 180 individual neurons (or nerve cells) in the inferior colliculus. The animals were placed in a dark chamber where a light-emitting diode (LED) would switch on in one of several predetermined locations. After the monkeys attended to and fixated on the light for a few fractions of a second, a short clip of white noise would play from speakers in the chamber. © 1996-2007 Scientific American, Inc

Keyword: Hearing; Vision
Link ID: 10900 - Posted: 06.24.2010

By LINDSEY TANNER CHICAGO -- The country's leading pediatricians group is making its strongest push yet to have all children screened for autism twice by age 2, warning of symptoms such as babies who don't babble at 9 months and 1-year-olds who don't point to toys. The advice is meant to help both parents and doctors spot autism sooner. There is no cure for the disorder, but experts say that early therapy can lessen its severity. Symptoms to watch for and the call for early screening come in two new reports. They are being released by the American Academy of Pediatrics on Monday at its annual meeting in San Francisco and will appear in the November issue of the journal Pediatrics and on the group's Web site _ http://www.aap.org/. The reports list numerous warning signs, such as a 4-month-old not smiling at the sound of Mom or Dad's voice, or the loss of language or social skills at any age. Experts say one in 150 U.S. children have the troubling developmental disorder. "Parents come into your office now saying 'I'm worried about autism.' Ten years ago, they didn't know what it was," said Dr. Chris Johnson of the University of Texas Health Science Center in San Antonio. She co-authored the reports. © 2007 The Associated Press

Keyword: Autism
Link ID: 10899 - Posted: 06.24.2010

By ALAN SCHWARZ Vin Ferrara, a former Harvard quarterback, was looking for an aspirin in his medicine cabinet when his eyes fixed upon a ribbed plastic bottle used to squirt saline into sinuses. Ferrara squeezed the bottle, then pounded on it — finding that it cushioned soft and hard blows with equal aplomb, almost intelligence. “This is it,” Ferrara declared. Three years later, Ferrara’s squirt bottle has led to a promising new technology to protect football players from concussions. Football helmets have evolved over more than a century from crude leather bonnets to face-masked, polycarbonate battering rams. But they still often fail to protect brains from the sudden forces that cause concussions. Studies have found that 10 to 50 percent of high school players each season sustain concussions, whose effects can range from persistent memory problems and depression to coma and death. Contemporary helmet manufacturers have made a point of improving protection against concussions. But experts suspect that Ferrara, who sustained several concussions as a player himself, has developed a radically effective design. Rather than being lined with rows of traditional foam or urethane, Ferrara’s helmet features 18 black, thermoplastic shock absorbers filled with air that — not unlike his squirt bottle — can accept a wide range of forces and still moderate the sudden jarring of the head that causes concussion. Moreover, laboratory tests have shown that the disks can withstand hundreds of impacts without any notable degradation in performance, a longtime drawback of helmets’ traditional foam. Copyright 2007 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 10898 - Posted: 06.24.2010

Troops exposed to explosions in Iraq and Afghanistan are to be checked for brain injury, the Ministry of Defence has confirmed. The MoD said questionnaires had been sent to troops to see if they had signs of mild traumatic brain injury (mTBI). The survey was triggered by fears in the US Army that up to 20% of soldiers were returning with the condition. Symptoms include memory loss, anxiety and depression. In 90% of cases they disappear within three months. The Guardian reported that the Pentagon had designated mTBI as one of the "signature injuries" suffered by soldiers coming back from Iraq. The MoD said it was collaborating with the US Army to investigate the condition, but a spokesman emphasised that it did not necessarily accept that the disorder was as widespread is it is believed to be by the Americans. The spokesman said: "It is a very, very complex area. We have no way of knowing whether that [the US assessment] is accurate because there is a level of dispute as to what constitutes mTBI." He said symptoms may last for as little as 72 hours - and had gone in 80% of cases within two weeks, and in more than 90% of cases within three months. The questionnaire-based self assessment is currently being trialled in Iraq and Afghanistan, and will be brought to all those who may be affected in the new year. The questionnaires are supported by a helpline and a website, and there is an mTBI treatment programme at the military rehabilitation centre at Headley Court in Surrey. The condition is caused by a blow to the head or by being close to an explosion. It can also be sustained in contact sports such as boxing or rugby. (C)BBC

Keyword: Brain Injury/Concussion
Link ID: 10897 - Posted: 10.27.2007

By Maureen Farrell Do you sweat at the thought of flying, giving a speech or even going to a party? Join the club: Anxiety disorders — including specific phobias, obsessive-compulsive disorder and post-traumatic stress disorders — afflict 40 million Americans aged 18 and older (18% of that group), according to the 2005 National Co-Morbidity study, a mental health survey. While fear is a natural (and practical) response to danger, phobias are exaggerated responses to situations that, in the cold light of day, aren't really all that dangerous. And yet they remain terribly difficult to overcome. A big reason has to do with the way most people respond to fear — by avoiding it. Whether it's closed spaces or packed audiences, the more you duck those tough spots, the more you'll fear them. "Catastrophic thoughts lead to fear, which leads to avoidance, which leads to more catastrophic thoughts," says Dr. Dennis Greenberger, psychologist and professor of clinical psychology at the University of California at Irvine. "It's a vicious cycle that exacerbates the fear over time." One weapon is Cognitive Behavioral Therapy (CBT), a form of psychotherapy that involves changing behaviors and thoughts to overcome depression, self-loathing and fear. CBT proponents believe that bad feelings begin with bad thoughts; meet those head on, they say, and almost any fear can be tamed. © 2007 Forbes.com

Keyword: Emotions
Link ID: 10896 - Posted: 06.24.2010

CBC News Lowered dopamine levels prompt obese individuals to eat more food in an attempt to achieve that "feel-good" feeling that the chemical generates, a new study suggests. Receptors of dopamine, a chemical in the brain that is associated with pleasure, were found to be lower in obese rats, and their levels rose when food intake was restricted. The study was conducted at the U.S. Department of Energy's Brookhaven National Laboratory. The findings are published in the journal Synapse and are now available online. "This research corroborates brain-imaging studies conducted at Brookhaven that found decreased levels of dopamine D2 receptors in obese people compared with normal-weight people," said Brookhaven neuroscientist Panayotis Thanos, lead author of the study. "Dopamine is one of the neurotransmitters modulating the reinforcing properties of food," reads the report. The researchers aren't sure whether obesity leads to reduced dopamine receptor levels or whether the receptors are themselves responsible for making people obese. However, their studies show that decreasing food intake helped increase dopamine receptor sensitivity. © CBC 2007

Keyword: Obesity
Link ID: 10895 - Posted: 06.24.2010

SANTIAGO - Chilean scientists have made a discovery in the brains of rats that they say may help treat drug addiction and ease the side effects of some medications. Researchers at the Pontifical Catholic University in Santiago say they identified a region of the brain, the insular cortex, that plays an important role in drug craving. Tests on amphetamine-addicted laboratory rats showed that when the insular cortex was deactivated by injecting a drug that halted brain cell activity, the rats showed no signs of addiction. When the insular cortex was reactivated, the rats again showed signs of craving amphetamines, according to the research to be published in Friday's edition of the journal Science. "(This) indicates to us that this region of the brain processes information about the physiological states of the body and may guide behavior," said Fernando Torrealba, one of the researchers. In a second experiment, Torrealba's team injected rats with lithium, a drug used to treat mental illness that has side effects including malaise and intestinal pain. (c) Reuters 2007.

Keyword: Drug Abuse
Link ID: 10894 - Posted: 10.26.2007

WASHINGTON - Your brain is supposed to fire a "hold your horses" signal when faced with a tough choice. But a brain implant that stops the tremors of Parkinson's disease may block that signal — a new explanation for why some Parkinson's patients become hugely impulsive. Scientists have long known that anti-Parkinson medications occasionally spark compulsions like pathological gambling. Research published Thursday found another treatment, a pacemaker-like brain implant, can trigger a completely different kind of impulsiveness. How different? The drugs leave a subset of patients unlikely to learn from bad experiences, like a losing poker hand. The brain implant doesn't hinder learning. In contrast, those patients can make hasty decisions as the brain loses its automatic tendency to hesitate when faced with conflict, University of Arizona researchers reported online in the journal Science. In fact, the first patient they studied displayed an alarming example when he saw something across the room he wanted and tried to dash over without his wheelchair. Neuroscientist Michael Frank had to catch the man before he fell. "Deep brain stimulation," or DBS, involves placing electrodes into a small region called the subthalamic nucleus, an area important for controlling movement. But it also is where scientists believe the brain yells: "Stop, weigh your options!" Copyright 2007 The Associated Press.

Keyword: Parkinsons; Emotions
Link ID: 10893 - Posted: 06.24.2010

Heidi Ledford An analysis of 50,000-year-old Neanderthal DNA suggests that at least some of the ancient hominids probably had pale skin and red hair. The findings, published this week in Science 1, are based on the sequence of a single gene, called mc1r . Humans with a less functional form of the MC1R protein are more likely to be fair skinned — an adaptation that may have helped inhabitants of high latitudes synthesize vitamin D more efficiently in limited sunlight. Analyses of Neanderthal DNA are always subject to the problem of fossil samples being contaminated with modern human DNA in the lab or the field. But Carles Lalueza-Fox of the University of Barcelona, Spain, with Holger Römpler of the University of Leipzig in Germany and colleagues, found that the mc1r gene in two European Neanderthal fossils they studied contained a single base-pair change that seems to be unique to Neanderthals. “We were lucky we found a variant that had not been described in modern humans,” says co-author Michael Hofreiter of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. “That made it unlikely to be human contamination.” The researchers re-sequenced the applicable region of the gene multiple times, then asked two additional labs to repeat the experiments using fresh extracts. They also sequenced fragments of the mc1r gene from the researchers in each lab, as well as the archaeologists and palaeontologists who had handled the fossils. And they searched databases containing mc1r sequence from 2,800 humans and tested several hundred additional samples. © 2007 Nature Publishing Group

Keyword: Evolution; Sexual Behavior
Link ID: 10892 - Posted: 06.24.2010

Roxanne Khamsi Rats addicted to amphetamines temporarily 'forget' their drug cravings after receiving targeted brain injections of lidocaine, a medication commonly used by dentists to numb patients' gums. Researchers say that the medication worked by inactivating an area of the brain known as the insular cortex or insula, which has previously been implicated in controlling drug addiction. They hope that altering activity in the insula might one day work to treat drug addiction in people. Other experts, however, note that addiction is a complex problem that seems to involve multiple brain regions. Previous research has shown that brain regions such as the prefrontal cortex and nucleus accumbens drive drug cravings by responding to reward signals from the chemical dopamine in the brain. But Fernando Torrealba at the Pontifical Catholic University of Chile in Santiago believed that the insula, a brain region located behind the ears, might somehow exert a large influence on addiction. The insula appears to monitor the body's heart rate, blood sugar, and other functions, and prompt conscious feelings of hunger and cravings in response. Recent work has shown that damage to this area can cause smokers to give up cigarettes overnight. © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse
Link ID: 10891 - Posted: 06.24.2010

Microscopic nematode worms are among the most-studied organisms in biology and genetics-- revealing the role of genes in addiction, obesity, and even longevity. Now researchers at the University of Utah have demonstrated they can make them behave like the opposite sex by activating a gene in their brains. "A female avoids other females and males are attracted to females. And so what we can do is swap those behaviors," says Howard Hughes Medical Institute investigator Erik Jorgensen. "But what's really important is that we can identify the circuits in the brain that underlie that behavior. So we have a group of cells that we can now manipulate and demonstrate how this whole process works-- how does the brain work." While the worm, C. elegans, only has 302 nerve cells, "The nerve cell in a worm is exactly how a nerve cell in the human brain works," Jorgensen says. "So if we can understand it in a worm we'll be able to understand how the brain works in the human and that is our goal." As Jorgensen, Jamie White and their colleagues wrote in the journal, Current Biology, the study showed that in worms, sexuality is hard-wired in the brain and is not affected by the body or hormones. © ScienCentral, 2000-2007.

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 10890 - Posted: 06.24.2010

A component of cannabis in small doses can act as a powerful antidepressant, but too much of the drug can cause the polar opposite effect, finds a study released Wednesday. The study, published in the Oct. 24 issue of the Journal of Neuroscience, was conducted jointly by McGill University and a research institute affiliated with the University of Montreal. It finds that a form of THC, the active ingredient in cannabis or marijuana, increased serotonin levels in the brains of laboratory rats when given in low doses. The depletion of serotonin, a neurotransmitter that controls moods, leads to depression and in some cases psychosis. Anti-depression medications work by increasing the amount of serotonin in the brain. However, when the doses were increased in the rats, the effect was described as completely reversed. McGill researcher Francis Bambico said the study seems to support anecdotal evidence that human smokers of marijuana experience positive effects, but they also experience unwanted effects like anxiety and agitation. © The Canadian Press, 2007

Keyword: Drug Abuse; Depression
Link ID: 10889 - Posted: 06.24.2010

NEW YORK - Cigarette smoking and a family history of alcoholism both alter how women perceive sweet foods and what foods they crave, according to studies conducted by two researchers from the Monell Chemical Senses Center in Philadelphia. Marta Yanina Pepino and Julie A. Mennella found that women who smoked were less sensitive to sweet taste than women who never smoked. Women who smoked needed higher concentrations of sugar to detect a sweet taste, and the more years a woman smoked, the less she was able to perceive a sweet taste. “Smoking dulls sweet taste sensitivity,” Pepino and Mennella noted in a joint email to Reuters Health. “Whether this reduced sensitivity for sweets helps smokers control their weight is an important question that is not addressed in the current study.” The researchers also found that cigarette smoking leads to increased food cravings, particularly for starchy carbohydrates and high-fat foods. “We found that food cravings were associated with nicotine dependence ... the more intense the cravings for cigarettes, the more frequent the cravings for foods high in fat and carbohydrates,” Pepino explained. Copyright 2007 Reuters.

Keyword: Drug Abuse; Chemical Senses (Smell & Taste)
Link ID: 10888 - Posted: 06.24.2010

By SCOTT HAIG She was worried about the lump and worried about the children who were worrying about her. She was, however, most worried about the anesthesia. "What if I don't wake up?" just wasn't a question I could answer sufficiently for her. Some people take no solace in statistics (that, for example, there are two or three deaths per 1 million patients anesthetized) — these patients are the medical cousins of the folks still crossing the country by train or bus rather than "risking the airplane." So I warned her that there might be a little pain and agreed to do her biopsy under a local anesthetic — but only if she would allow an anesthesiologist in the room, just in case. The lump was growing near — maybe on — the inner end of Ellen's collarbone, meaning that during the biopsy I might have to use a tool that goes "crunch." It's pretty hard to numb up bone with a local anesthetic so I was glad to have Frank, the anesthesiologist, there at the head of the table with some IV sedatives, in case Ellen got panicky or was in too much pain. She was adamant about not going under, but agreed to "some sedation" if we thought it was necessary. I can understand not wanting to lose consciousness. It's arguably the most precious thing we have. And although serious complications from anesthesia are truly rare these days, so are bone tumors — and she clearly had one of those. Ellen had a history of cancer too — it had not been a cancer that was likely to spread to the bone and there hadn't been any sign of it for years, but it had been a malignancy. © 2007 Time Inc.

Keyword: Learning & Memory
Link ID: 10887 - Posted: 06.24.2010

Roxanne Khamsi Two regions of the brain linked to optimism have been discovered by researchers. The identification of the sites that signal positive thinking could shed light on the causes of depression, they say. The US team says that the act of imagining a positive future event – such as winning an award or receiving a large sum of cash – activates two brain areas known as the amygdala and the rostral anterior cingulated cortex (rACC). The finding lends weight to earlier studies that suggested these brain regions malfunction in depression and hint at new ways of diagnosing the disorder. Elizabeth Phelps at the New York University, US, and colleagues measured how optimistic 15 volunteers were using a standard questionnaire. The researchers then asked these subjects to lie in a brain scanner and reflect on one of a number of potential scenarios. For example, in one part of the trial, subjects followed specific instructions to recall a negative event in the past, such a funeral attended in the past five years. In another part of the experiment they had to imagine what it would be like to be involved in a car crash in the near future. At other points in the study subjects had to reflect on positive events such as winning an award in the past or receiving a large sum of cash in the future. © Copyright Reed Business Information Ltd

Keyword: Emotions
Link ID: 10886 - Posted: 06.24.2010

Smoking large amounts of cannabis for therapeutic reasons may increase rather than reduce pain, a US study suggests. The pain-relieving qualities of cannabis have long been hailed, and several countries have made it available for medicinal purposes. But quantity is key, according to the study in the journal Anesthesiology. University of California researchers found moderate use had the greatest impact on pain in 15 volunteers, while large doses actually made pain worse. The team recruited 15 healthy volunteers, in whom pain was induced by injecting capsaicin - the "hot" chemical found in chilli peppers - under their skin. They were then given cannabis to smoke. The strength of the dose was determined by the tetrahydrocannabinol content, which is the main active chemical in cannabis. Some of the volunteers were given a placebo. Five minutes after smoking the drug, none of the doses had any effect on the pain felt. But 45 minutes later, those who had smoked the moderate dose said their pain was much better, while those who consumed high doses said it had got worse. They did, however, feel "higher" than counterparts who had taken moderate doses. Dr Mark Wallace, the lead researcher, said the findings could have implications for the way medicinal cannabis was offered, both in pure and drug form. (C)BBC

Keyword: Pain & Touch; Drug Abuse
Link ID: 10885 - Posted: 10.24.2007

By JANE E. BRODY For decades, I assumed I needed to sleep just five to six hours a night. I nearly always awoke before the alarm in the morning. But I also nearly always fell asleep at concerts and plays, on the subway or while reading or riding in a car. Last summer, when I was able to operate completely on my body’s own time clock, I discovered that it preferred seven to seven and a half hours of sleep. I also discovered that when I slept at night for however long my body wanted to, my daytime dozes all but disappeared. Surveys have shown that few of us past infancy and toddlerhood are receiving the amount of sleep our bodies and brains need to restore them to full function for the day ahead. And many of us — children, teenagers and adults of all ages — may pay a hefty price. As noted elsewhere in this issue, crucial brain functions occur in sleep that cannot be reproduced when we are awake. More than intellectual prowess can suffer; though definitive data are still lacking, a chronic shortage of sleep has been linked to serious physical ills, including heart disease, diabetes and obesity. Copyright 2007 The New York Times Company

Keyword: Sleep
Link ID: 10884 - Posted: 06.24.2010

WASHINGTON - Teenagers who smoke are five times more likely to drink and 13 times more likely to use marijuana than those who are not smokers, according to a report issued on Tuesday. The report by Columbia University's National Center on Addiction and Substance Abuse presented further evidence linking youth smoking to other substance abuse and spotlighted research on how nicotine affects the adolescent brain. "Teenage smoking can signal the fire of alcohol and drug abuse or mental illness like depression and anxiety," Joseph Califano, who heads the center and is a former U.S. health secretary, said in a telephone interview. The report analyzed surveys conducted by the U.S. Substance Abuse and Mental Health Services Administration and other data on youth smokers. Most smokers begin smoking before age 18. Smokers ages 12 to 17 are more likely drink alcohol than nonsmokers — 59 percent compared to 11 percent, the report found. Those who become regular smokers by age 12 are more than three times more likely to report binge drinking than those who never smoked — 31 percent compared to 9 percent. Binge drinking was defined as having five drinks or more in a row. © 2007 Microsoft

Keyword: Drug Abuse; Development of the Brain
Link ID: 10883 - Posted: 06.24.2010