By C. CLAIBORNE RAY Q. Does extra mental effort burn more calories? A. Yes, “but it would take years for the difference to show up on the scales,” said David A. Levitsky, professor of nutrition and psychology at Cornell University. “It is true that the metabolic rate increases when engaged in mental activity,” Dr. Levitsky said. “However, the amount of calories in terms of total daily intake is trivial.” The amount of energy spent in all the different types of mental activity is rather small, he said. Studies show that it is about 20 percent of the resting metabolic rate, which is about 1,300 calories a day, not of the total metabolic rate, which is about 2,200 calories a day, so the brain uses roughly 300 calories. “There are good, sophisticated studies that show that concentrated mental activity, like doing a difficult multiplication problem in your head, increases the glucose uptake to the brain,” he said. By how many calories? Less than, say, 20 calories of the 300, he estimated. But you do not engage that long in such an activity, he said, so the difference might amount to only about 10 calories a day. That means thinking hard is not a good way to lose weight. Copyright 2008 The New York Times Company

Keyword: Miscellaneous
Link ID: 12002 - Posted: 06.24.2010

By DEIRDRE VAN DYK If you have ever struggled with a difficult decision — new job vs. new boyfriend, sports car vs. minivan, read the book vs. see the movie — you have likely also been offered a heap of decision-making wisdom. Make a list of pros and cons. Go with your gut. Sleep on it. It was this last bit of advice — sleep on it — espoused in a paper by Dutch researchers and published in the journal Science in 2006, that really irked Ben Newell, a researcher himself at the University of New South Wales in Australia. That paper suggested that people might be better off relying on unconscious deliberation to make complex decisions — despite an abundance of scientific evidence to the contrary — given that the human brain can reasonably only focus on a few things at a time. Once people have all the necessary information to make a decision, the paper found, too much conscious deliberation could lead to unnecessary attention given to extraneous factors. Newell's answer to the Science paper is called "Think, Blink or Sleep on It? The Impact of Modes of Thought on Complex Decision Making," co-authored with colleagues at the University of New South Wales and the University of Essex in England, and published in the most recent issue of the Quarterly Journal of Experimental Psychology. It took four experiments to make the point, but Newell's conclusion is that unconscious deliberation is no more effective than conscious deliberation — using lists of pros vs. cons, for example — for making complex decisions, and that if anything, people who deliberate methodically are better off. "If you have to make decisions, you have to do your homework," says Newell. "There is no magic unconscious." © 2008 Time Inc.

Keyword: Learning & Memory; Emotions
Link ID: 12001 - Posted: 06.24.2010

-- Neanderthals were not as stupid as they have been portrayed, according to new research showing their stone tools were as good as those made by the early ancestors of modern humans, Homo sapiens. The findings by a team of scientists at British and U.S. universities challenge the assumption that the ancestors of people living today drove Neanderthals into extinction by producing better tools. The research could lead to a fresh search for explanations about why Neanderthals vanished from Europe around 28,000 years ago, after living alongside modern humans for some 10,000 years. Experimental archaeologist Metin Eren, from the University of Exeter in southwest England, said: "Our research disputes a major pillar holding up the long-held assumption that Homo sapiens were more advanced than Neanderthals. "It is time for archaeologists to start searching for other reasons why Neanderthals became extinct while our ancestors survived. "Technologically speaking, there is no clear advantage of one tool over the other. When we think of Neanderthals, we need to stop thinking in terms of 'stupid' or 'less advanced' and more in terms of 'different,'" Eren said. © 2008 Discovery Communications, LLC.

Keyword: Evolution
Link ID: 12000 - Posted: 06.24.2010

Priya Shetty What if you could tell whether a man is husband material just by peering at his genes? There has been speculation about the role of the hormone vasopressin in humans ever since we discovered that variations in where receptors for the hormone are expressed makes prairie voles strictly monogamous but meadow voles promiscuous; vasopressin is related to the "cuddle chemical" oxytocin. Now it seems variations in a section of the gene coding for a vasopressin receptor in people help to determine whether men are serial commitment-phobes or devoted husbands. Hasse Walum at the Karolinska Institute in Stockholm, Sweden, and colleagues looked at the various forms of the gene coding for a vasopressin receptor in 552 Swedish people, who were all in heterosexual partnerships. The researchers also investigated the quality of their relationships. They found that variation in a section of the gene called RS3 334 was linked to how men bond with their partners. Men can have none, one or two copies of the RS3 334 section, and the higher the number of copies, the worse men scored on a measure of pair bonding. Not only that, men with two copies of RS3 334 were more likely to be unmarried than men with one or none, and if they were married, they were twice as likely to have a marital crisis. © Copyright Reed Business Information Ltd

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 11999 - Posted: 06.24.2010

By LINDSEY TANNER CHICAGO – Children born to older fathers face a greater chance of developing bipolar disorder, according to one of the largest studies linking mental illness with advanced paternal age. Previous research has connected schizophrenia and autism with older dads, and a Danish study published last year added bipolar disorder to the list. The new study led by researchers at Sweden's Karolinska Institute strengthens the evidence. The leading theory is that older men's sperm may be more likely to develop mutations. Even so, the odds of a person becoming bipolar are so low that the study's authors said it shouldn't dissuade older men from becoming fathers. Researchers analyzed Swedish national registry data from more than 80,000 people, including 13,428 with bipolar disorder who were born between 1932 and 1991. The risks started increasing around age 40 but were strongest among those 55 and older. Children born to these dads were 37 percent more likely to develop bipolar disorder than those born to men in their 20s. They also faced more than double the risk of developing bipolar disorder before age 20. Scientists call that early onset disease, and while they have long known that bipolar disorder tends to run in families, early onset disease has been thought to be most strongly linked with genetics. © 2008 Yahoo! Inc.

Keyword: Schizophrenia; Genes & Behavior
Link ID: 11998 - Posted: 06.24.2010

NEW YORK - Dysfunction in a portion of the brain may explain some of the symptoms of fibromyalgia syndrome, researchers suggest in a paper published in the Journal of Rheumatology Dr. Yasser Emad, of Cairo University, Egypt, and colleagues used proton magnetic resonance spectroscopy to examine the function of the hippocampus in 15 patients with fibromyalgia syndrome and in 10 healthy women who were the same age as the other patients. The hippocampus is located deep in the front portion of the brain involved in regulating emotions and memory. Functionally, the hippocampus is part of the olfactory cortex, which is important to the sense of smell. Story continues below ↓advertisement Using spectroscopy, the researchers calculated levels of hippocampus levels of the brain chemicals N-acetyl aspartate (NAA), choline, creatine, along with their ratios, and compared the findings between the two groups. All study participants also underwent assessments of sleep patterns, cognitive function, and symptoms of depression. The number of tender points on the body was assessed in all patients and a visual analog scale was used to measure pain. Patient age averaged 35.7 years, and their average disease duration was 18.1 months. All of the patients had cognitive functional impairments on the Mini-Mental State Examination, eight (35.5 percent) were depressed according to the Hamilton Depression Scale, and nine (60 percent) had sleep disturbances. None of the control subjects had any problems in these areas. Copyright 2008 Reuters.

Keyword: Pain & Touch
Link ID: 11997 - Posted: 09.01.2008

By MATT APUZZO WASHINGTON -- The Bush administration can prohibit meat packers from testing their animals for mad cow disease, a federal appeals court said Friday. The dispute pits the Agriculture Department, which tests about 1 percent of cows for the potentially deadly disease, against a Kansas meat packer that wants to test all its animals. Larger meat packers opposed such testing. If Creekstone Farms Premium Beef began advertising that its cows have all been tested, other companies fear they too will have to conduct the expensive tests. The Bush administration says the low level of testing reflects the rareness of the disease. Mad cow disease has been linked to more than 150 human deaths worldwide, mostly in Great Britain. Only three cases have been reported in the U.S., all involving cows, not humans. ad_icon A federal judge ruled last year that Creekstone must be allowed to conduct the test because the Agriculture Department can only regulate disease "treatment." Since there is no cure for mad cow disease and the test is performed on dead animals, the judge ruled, the test is not a treatment. The U.S. Court of Appeals for the District of Columbia Circuit overturned that ruling, saying diagnosis can be considered part of treatment. © Copyright 1996-2008 The Washington Post Company

Keyword: Prions
Link ID: 11996 - Posted: 06.24.2010

What happens when linguistic tools used to analyze human language are applied to a conversation between a language-competent bonobo and a human? The findings, published this month in the Journal of Integrative Psychological and Behavioral Science, indicate that bonobos may exhibit larger linguistic competency in ordinary conversation than in controlled experimental settings. The peer-reviewed paper was written by Janni Pedersen, an Iowa State University Ph.D. candidate from Denmark whose interests in the language-competent bonobos at Great Ape Trust of Iowa led her to the United States, and William M. Fields, director of bonobo research at Great Ape Trust. Their findings run counter to the view among some linguists, including the influential Noam Chomsky, professor emeritus of linguistics at the Massachusetts Institute of Technology, who argue that only humans possess and use language. In his hierarchy of language, Chomsky believes that language is part of the genetic makeup of humans and did not descend from a single primitive language evolved from the lower primate order, and it must include formal structures such as grammar and syntax. Fields said the publication opens an important new chapter in a decades-long debate about the linguistic capabilities of apes. "The resistance to this in the scientific community is enormous," he said. "For the first time, we have a student who is using linguistic tools that have normally been applied to humans now being applied to non-humans. This is a move toward using the kinds of methodology that are appropriate in ape language, based on Savage-Rumbaugh's 1993 monograph, Language Comprehension in Ape and Child." © 2002-2008 redOrbit.com.

Keyword: Language; Evolution
Link ID: 11995 - Posted: 06.24.2010

Rachel Nowak Far from being a completed masterpiece, some parts of the brain are works-in-progress, continuously churning out new cells. Now we may know why the brain goes to all that trouble. In mice at least, it appears that fresh brain cells are key to learning and memory. By watching how genetically altered mice tried to learn and memorise the location of a hiding hole without the help of new brain cells, a team led by Ryoichiro Kageyama of Kyoto University in Japan has shown that new brain cells are essential for learning and memory. "It was always unclear whether neurogenesis in the adult was essential for normal brain function, or whether it was an innocent bystander. This shows that it's essential," says Rodney Rietze of the Queensland Brain Institute in Brisbane, Australia. Kageyama's team created a strain of mice engineered so that when they were given a drug, newly made brain cells in the hippocampus produced proteins that killed the cells. The hippocampus is essential for learning and memory. The team then looked at how well the mice learned to find a hiding hole, a standard test of learning and memory. "Usually a mouse remembers the hole after one or two days' training, and will still remember it a week later. These mice took five or six days to remember, and then totally forget it one week later," says Kageyama. © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory; Neurogenesis
Link ID: 11994 - Posted: 06.24.2010

More people than previously thought could be at higher risk of having a stroke caused by their antipsychotic drugs, say UK scientists. Previous research suggested only some types of the drug increased the risk, particularly for people with dementia. However a study published in the British Medical Journal says all forms of antipsychotics boost the risk, in all patients. A mental health charity said patients on the drugs must be closely monitored. Antipsychotic drugs are generally used to control psychotic symptoms in patients with disorders such as schizophrenia, and some severe forms of depression. They are also thought to be widely used to control symptoms of dementia such as aggression, leading to accusations they were being used unnecessarily as a "chemical cosh" in some circumstances. They fall into two types - newer "atypical" and older "typical" antipsychotics. When the first concerns were raised in 2002, these focused on the "atypical" drugs. These worries led to a recommendation from drug safety watchdogs in the UK that they not be given to people with dementia, and the government has been urged to strengthen this in England in its forthcoming dementia strategy. The latest findings, from researchers at the London School of Hygiene and Tropical Medicine, confirm the fears over dementia patients, but raise wider concerns. They identified 6,700 patients from a GP database, all with an average age of 80, and concluded that there was more than a tripling of risk for dementia patients taking any sort of anti-psychotic drug. Patients without dementia taking any sort of antipsychotic had a 40% increase in risk. The researchers repeated the recommendation that patients with dementia should not be prescribed these drugs. (C)BBC

Keyword: Schizophrenia; Alzheimers
Link ID: 11993 - Posted: 08.30.2008

By Matt McGrath Researchers in the US say that they have solved the mystery of why flies are so hard to swat. They think the fly's ability to dodge being hit is due to its fast acting brain and an ability to plan ahead. High speed, high resolution video recordings revealed the insects quickly work out where a threat is coming from and prepare an escape route. The research suggests that the best way of swatting a fly is to creep up slowly and aim ahead of its location. The study has been published in the journal Current Biology. Most people will have experienced the curiously frustrating sensation of carefully attempting to swat a fly, only to swing and miss while the intrepid insect buzzes off to safety. Over the years there have been different theories put forward to explain the fly's uncanny ability to outwit our whacking endeavours. But scientists at the California Institute of Technology (Caltech) say it is down to quick-fire intelligence and good planning. They filmed a series of experiments with fruit flies and a looming swatter. The researchers discovered that long before the fly leaps it calculates the location of the threat and comes up with an escape plan. Flies put their bodies into pre-flight mode very rapidly - Within 100 milliseconds of spotting the swatter they can position their centre of mass in the right way so that a simple extension of their legs propels them away from any threat. The scientists found that flies were able to put themselves into this rapid reaction position no matter whether they were grooming, feeding or simply walking. According to Caltech's Professor Michael Dickinson this illustrates the speed and complexity of the fly's brain.

Keyword: Miscellaneous
Link ID: 11992 - Posted: 08.30.2008

By Susana Martinez-Conde and Stephen L. Macknik The eyes are the windows to the soul. This fact is why we ask people to look us in the eye and tell us the truth. Or why we get worried when someone gives us the evil eye or has a wandering eye. Our everyday language is full of expressions that refer to where people around us are looking. Particularly if they happen to be looking in our direction. View Eye Illusions Slide Show As social primates, humans are very interested in determining the direction of gaze of other humans. It’s important for evaluating their intentions, and critical for forming bonds and negotiating relationships. Lovers stare for long stretches into each other’s eyes, and infants focus intently on the eyes of their parents. Very young babies look at simple representations of faces (such as smileys) for longer than they look at similar cartoonish faces in which the eyes and other features have been scrambled. In this slide show, we’re going to investigate a series of illusions that take advantage of the way the brain processes eyes and gaze. It turns out that it’s fairly easy to trick us into thinking that someone is looking somewhere else, or that Albert Einstein is actually Marilyn Monroe. © 1996-2008 Scientific American Inc.

Keyword: Vision
Link ID: 11991 - Posted: 06.24.2010

Jonah Berger, a professor of marketing at the University of Pennsylvania, made news a few months ago when he published the results of a study demonstrating that where people cast ballots affects how they vote. Although voters think they are making rational decisions based solely on the issues and facts, they are actually subtly influenced by a long list of other variables, most of which operate at an unconscious level. Mind Matters editor Jonah Lehrer chats with Berger about what this new research can teach us about elections, expensive clothing and the human brain. LEHRER: Your most recent paper found that voters are more likely to approve a sales tax increase when voting in a school. Why? What do you think is driving this effect? BERGER: We build on behavioral priming research, which finds that cues or stimuli in the environment, such as the things we see, can activate related concepts in our mind that carry over to influence behavior, even outside our awareness. In a classic study, for example, participants exposed to elderly related words ended up walking more slowly leaving the experiment. The idea is that the words activated the elderly stereotype, which includes walking slowly, and such thoughts influenced behavior. Similarly, in the case of polling locations, seeing lockers, desks and other things associated with schools might activate norms (such as the urge to take care of children) or identities (that is, being a parent) that then shift people to vote to support school funding. © 1996-2008 Scientific American Inc.

Keyword: Emotions
Link ID: 11990 - Posted: 06.24.2010

Jessica Marshall -- Tiny orange clownfish, made famous by the Disney character Nemo, use the smell of leaves and anemones in the water to find their way home on the coral reef. That's the finding of a new study using a clever apparatus to measure the fishes' preference for water carrying different odors. A team led by Geoffrey Jones of James Cook University in Townsville, Australia surveyed waters around Papua New Guinea for clownfish populations. "The boat captain said, 'If you want to find the orange clownfish, you have to find islands. The fish need to see trees,'" said study lead author Danielle Dixson. The survey confirmed this observation: "There's a huge statistical difference [in the numbers of clownfish] between where there are islands and where there are not islands." For reasons that are unknown, the two types of anemones that the region's clownfish call home only live near islands with trees and beaches and are not found on "islands" made only of reefs. But the fish have to search for these anemones, because after eggs hatch near the parents' home anemone, the larvae are carried away by ocean currents. About 11 days later, the juvenile fish settle back into a new anemone, somehow having found their way to their favored abodes. © 2008 Discovery Communications, LLC.

Keyword: Chemical Senses (Smell & Taste); Animal Migration
Link ID: 11989 - Posted: 06.24.2010

In the long run it’s not a guy’s looks that count. It’s his little clucks in the face of danger. A high rate of calling out in alarm turns out to be one of the clearest signs of a rooster with a successful sex life, says Chris Evans of Macquarie University in Sydney, Australia. A rooster that readily gives warning calls when danger looms tends to rank high in number of times hens accept him as a mate and in number of chicks sired, Evans, David R. Wilson and colleagues report in the September Animal Behaviour. A rooster may waggle a huge, ruby-red comb at hens, but if they’ve had a chance to get to know him, his splendor doesn’t mean success. In tests that mimic real life among fowl, behavior trumps looks. “As far as I know, their paper is the first to address the sexiness of alarm calling,” says Dan Blumstein of the University of California, Los Angeles, who has studied alarm calls in marmots. “Alarm calling is a classic problem in evolutionary biology,” Evans says. Squawking as a hawk circles or a fox sneaks up raises the chances of the squawker getting eaten. While the rest of the neighborhood may benefit, the alarm caller seems to be taking a puzzling altruistic risk. © Society for Science & the Public 2000 - 2008

Keyword: Sexual Behavior; Evolution
Link ID: 11988 - Posted: 06.24.2010

A brain chemical that plays a role in long term memory also appears to be involved in regulating how much people eat and their likelihood of becoming obese, according to a National Institutes of Health study of a rare genetic condition. Brain derived neurotrophic factor (BDNF) is, as its name implies, produced in the brain. Studies of laboratory animals have suggested it also helps control appetite and weight. The NIH study, appearing in the August 28 New England Journal of Medicine, provides the first strong evidence that BDNF is important for body weight in human beings as well. The NIH researchers studied children and adults with WAGR syndrome, a rare genetic condition. The researchers found that some of the people with this syndrome lack a gene for BDNF and have correspondingly low blood levels of the substance. The people in this subgroup also have unusually large appetites and a strong tendency towards obesity. “This is a promising new lead in the search for biological pathways that contribute to obesity,” said Duane Alexander, M.D., director of the NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development. “This finding may eventually lead to the development of new drugs to regulate appetite in people who have not had success with other treatments.”

Keyword: Obesity; Trophic Factors
Link ID: 11987 - Posted: 06.24.2010

By Tina Hesman Saey The protein increases with brain activity as patients recover from brain injury Amyloid-beta is a thinking brain’s protein. A new study involving people with severe brain injuries shows that as neuronal activity increases, levels of amyloid-beta in the brain also go up. A-beta, as the protein is sometimes called, is best known for causing plaques in the brains of people with Alzheimer’s disease. It is a normal component of the brain, but scientists don’t know what it does. Traumatic brain injuries increase the risk for Alzheimer’s disease. So to find out if brain injuries cause a spike in amyloid-beta levels that could lead to plaque formation, a team of researchers from Milan, Italy, and Washington University in St. Louis sampled fluid from the brains of 18 comatose patients. The researchers inserted devices in the patients’ brains to monitor pressure. A small catheter sipped up fluid that gathers between brain cells, and then the researchers tested the fluid for A-beta. What the researchers found was exactly the opposite of what they expected, says David L. Brody, a neurologist at Washington University who led the study with Sandra Magnoni of the Ospedale Maggiore in Milan. Instead of seeing a spike of A-beta soon after brain injury from falls, car accidents, assaults or hemorrhages, levels of the protein started low and rose as the patients improved, the team reports in the Aug. 29 Science. © Society for Science & the Public 2000 - 2008

Keyword: Alzheimers
Link ID: 11986 - Posted: 06.24.2010

By Nathan Seppa A gene variant may guard against a blinding eye disease that strikes the elderly A gene called TLR3 may play a pivotal role in the common form of age-related macular degeneration, the leading cause of blindness in the elderly. The new finding, reported online August 27 in The New England Journal of Medicine, reveals that roughly three in 10 people harbor a variant form of TLR3 that subdues its normal activity, seeming to provide a partial safeguard against the dry, common form of the eye disease. In the dry form of macular degeneration, deposits clutter the center of the retina, or macula, and can lead to cell death. That can damage vision to the point of blindness. A less-common form called wet macular degeneration causes vision loss as rogue blood vessels grow in the eye and leak, clouding the macula. In recent years, scientists have discovered several genes implicated in macular degeneration. With the new finding, TLR3, which encodes the protein Toll-like receptor 3, becomes the first gene associated exclusively with the dry form. Researchers tested more than 2,000 people with wet, dry or no macular degeneration. Those with the dry form were less likely than the others to carry the protective variant form of TLR3. © Society for Science & the Public 2000 - 2008

Keyword: Vision; Genes & Behavior
Link ID: 11985 - Posted: 06.24.2010

Early use of medication may be able to slow down progression of Parkinson's disease, preliminary research suggests. Patients who took the drug rasagiline soon after diagnosis had a less aggressive form of Parkinson's than those who did not take it until later. The international study involved more than 1,000 patients, but doctors stress it could be 10 to 15 years before the long-term benefits become clear. Details were presented at a neurological conference in Madrid. More than 120,000 people in the UK have Parkinson's and around 10,000 new cases are diagnosed each year. Symptoms of the progressive neurological disorder include shakes, memory loss and stiffening of the muscles. Rasagiline, also known as Azilect, is already approved for use by the NHS to ease symptoms of Parkinson's. However, some doctors are reluctant to prescribe medication at an early stage, due to concern that the effect can wane with time. The latest study, presented at the European Federation of Neurological Societies Congress, involved patients from the UK, US and Europe. It found that patients who took rasagiline immediately after diagnosis were in better shape after 18 months than those whose treatment with the drug was delayed by nine months. The researchers believe that the drug could work by creating a long lasting protection for brain cells. However, they stressed that many patients had been taking part in the study for just 18 months, and much more work was required to pin down the long-term impact. (C)BBC

Keyword: Parkinsons
Link ID: 11984 - Posted: 08.28.2008

Fat cells from people who are obese don't work properly compared with those from lean people, medical researchers have found. In Thursday's issue of the journal Diabetes, researchers in Philadelphia said they found major differences in fat cells taken from the upper thighs of six obese people and six lean subjects. "The fat cells we found in our obese patients were deficient in several areas," said the study's lead author, Dr. Guenther Boden, chief of endocrinology at Temple University's School of Medicine. "They showed significant stress on the endoplasmic reticulum, and the tissue itself was more inflamed than in our lean patients." The endoplasmic reticulum, or ER, is found in every cell, helping to synthesize proteins and monitor how they are folded, which is important for proper functioning. When the ER in fat cells were stressed, they produced proteins that lead to insulin resistance, the researchers said. Insulin resistance occurs when the body fails to effectively regulate the metabolism of fats, proteins and sugars. The condition can lead to Type 2 diabetes. © CBC 2008

Keyword: Obesity
Link ID: 11983 - Posted: 06.24.2010