by Virginia Hughes • The humpback whale is known as the gregarious, singing "gentle giant" of the sea. But the herring it inventively preys upon—one whale in a gang blows "air bubble nets" around a school of fish while another screams until the poor things are scared to the surface—would probably disagree with this assessment. In any case, the auditory and communicative behaviors within groups of humpbacks reveal remarkable intelligence. However, since whale specimens are rare—either harvested from beached whales or sick aquarium residents—scientists know only the basics of their brain surface anatomy and are virtually ignorant about what goes on underneath. But last summer, neuroscientists from Mount Sinai School of Medicine got their hands on one of these rare brain samples and studied it. Now they've published a thorough morphological analysis of the humpback brain, and have compared it to a host of other species. Their study, published in the Nov. 27 early online edition of the journal The Anatomical Record, reveals that the humpback brain contains many anatomical curiosities, including one type of neuron involved in high-level cognitive functions previously thought to be unique to primates. "Methodologically, it's a beautifully done study, and the results are really stunning," said neuroscientist Lori Marino of Emory University, who was not involved in the research. "[The presence of these neurons] tells us that these are animals with possibly a very sophisticated sense of social cognition." © Copyright 2005-2007 Seed Media Group, LLC

Keyword: Evolution
Link ID: 10493 - Posted: 06.24.2010

Mental illness poses a particular challenge for medical researchers trying to understand what is going on in patients' brains. Exploratory surgery is a tough sell. Instead, researchers turn to animal models of psychiatric ills, bearing in mind that a mouse will never show signs of hypochondria and a fruit fly will never buzz off to Vegas for a gambling addiction. Still, researchers have made headway against a lot of psychiatric ills by experimenting on animals, and a neuroengineering team led by Stanford University's Karl Deisseroth reports on a possible answer to one of the mysteries behind depression. "Depression raises all kinds of questions," Deisseroth says. "It has all sorts of symptoms and responds to a variety of drugs that act in different ways." Almost 15 million people nationwide suffer from a "major depressive disorder," according to the federal National Institute of Mental Health. The researchers looked at a rat known for exhibiting a symptom of depression — hopelessness. "They give up on tasks easily," he says. The same rats respond to treatment with fluoxetine, an antidepressant commonly given to people as well. The team treated some of their rats to 5-to-7 weeks of stress, such as changing their sleeping and feeding schedules, tilting their cages and using strobe lights. Some of the rats received antidepressants and some didn't. Copyright 2007 USA TODAY,

Keyword: Depression
Link ID: 10492 - Posted: 06.24.2010

Blocking a molecule in the brain may "cure" post-traumatic stress disorder, according to US researchers. They showed that inhibiting a specific enzyme removed fear in mice and report to journal Nature Neuroscience that the finding may lead to new treatments. Around a third of people may suffer PTSD after an exceptionally traumatic event, such as a terrorist attack or a natural disaster. Experts said it was early days but the findings were worth exploring further. There is currently no treatment for PTSD although antidepressants and sleeping pills can help with the symptoms, which include flashbacks, anger, anxiety and depression. Professor Li-Huei Tsai and colleagues in the Brain and Cognitive Sciences Department at MIT looked at the effects of an enzyme called Cdk5 in the brains of genetically engineered mice which had been given mild foot shocks. When re-exposed to the same environment but without the shocks, mice in whom the researchers had increased levels of Cdk5 activity had difficulty letting go - or extinguishing - the memory of the foot shock and continued to freeze in fear. But in mice whose Cdk5 activity was blocked, the bad memory of the shocks disappeared when the mice learned that they no longer needed to fear the environment where the foot shocks had occurred. The enzyme activity was modified in the hippocampus - the brain's centre for storing memories. (C)BBC

Keyword: Stress; Learning & Memory
Link ID: 10491 - Posted: 07.16.2007

Scientists have discovered a protein which may help to slow, or even reverse symptoms of Parkinson's disease. Parkinson's destroys nerve cells that produce the brain chemical dopamine, causing movement and balance problems. Finnish researchers found the new molecule can prevent degeneration of these cells - and help damaged cells start to recover. Their paper, featured in Nature, showed symptoms eased in rats given injections of the protein. Current anti-Parkinson's drugs do not stop nerve cells from degenerating and dying, and their effects can be patchy and short-lived. The researchers, from the University of Helsinki, believe the new molecule - dubbed conserved dopamine neurotrophic factor (CDNF) - has great potential as a treatment. Previous research has centred on another protein - GDNF - which some research had suggested could improve symptoms in Parkinson's patients. However, other studies have thrown doubt over the effect of the protein - and raised serious safety issues. The Helsinki team decided to search for related proteins - known as growth factors - which worked in a similar way, but were likely to be better tolerated. They found that CDNF, unlike other similar growth factors, was specific to brain nerve cells. Experiments were carried out on rats bred to show symptoms similar to Parkinson's. In tests, CDNF protected 96% of nerve cells in the brains of the animals from degeneration. (C)BBC

Keyword: Parkinsons
Link ID: 10490 - Posted: 07.14.2007

Kavita Mishra, Chronicle Staff Writer Want to forget something? Just let your brain know. New research suggests that people can push out memories, even highly emotional ones, simply by deciding to do so. The researchers believe the new findings will help scientists understand disorders like post-traumatic stress disorder and obsessive-compulsive disorder, in which the brain's mechanism of suppressing unwanted memories may be dysfunctional, said lead author Brendan Depue, a graduate student in neuroscience and clinical psychology at the University of Colorado at Boulder. But many experts are wary of linking the findings -- published today in the online journal Science -- to debilitating disorders like PTSD. They believe the mind developed to actively forget some memories to keep from cluttering the brain with unpleasant memories and irrelevant information, like unnecessary phone numbers. But highly emotional memories may never be forgotten. "We have these mechanisms to try to stamp out and suppress these things when we want to try to avoid uncomfortable thoughts. On the other hand, we do know that very serious emotional memories are, in general, very remembered," UC Berkeley psychologist Art Shimamura said. Stanford psychologist Anthony Wagner said the findings help explain how the brain works to forget some things and not others. Specific areas of the brain are used in order to help us forget. © 2007 Hearst Communications Inc.

Keyword: Learning & Memory
Link ID: 10489 - Posted: 06.24.2010

By David Douglas NEW YORK (Reuters Health) - Examining the blood vessels in the retina of the eye may give a clue to the mental status of elderly people and their risk of developing dementia, researchers report. The presence of retinal damage, or retinopathy, "is a marker of early damage to the blood vessels in the brain, and is a harbinger of future stroke risk," senior investigator Dr. Tien Yin Wong of the University of Melbourne Centre for Eye Research, Australia, told Reuters Health. In order to see if retinopathy might also be linked to cognitive function and dementia, Wong and colleagues studied retinal photographs of 2211 people aged 69 to 97 years. More than half of them had hypertension, i.e., high blood pressure. After adjusting for factors such as age, diabetes, and smoking status, subjects with retinopathy had lower scores on a standard test of cognitive status than those without (39 versus 41), the team reports in the medical journal Stroke In subjects with high blood pressure, retinopathy doubled the likelihood of having dementia. No such relationship was seen in those without high blood pressure. © 1996-2007 Scientific American, Inc

Keyword: Alzheimers; Vision
Link ID: 10488 - Posted: 06.24.2010

Children with Fragile X Syndrome – the most common, inherited type of mental retardation – have delayed learning and language, poor coordination and repetitive behaviors. Now researchers at MIT have hope of reversing those symptoms after a successful study in mice. Mansuo Hayashi, lead researcher of the study, explains why a treatment is needed. "With the modern human genetic diagnosis, I think we could identify the genetic disorders prior to birth, but in many cases, with even with the advanced technology, the abnormality won't show up until after birth. … Therefore it's important to find a drug that will treat or delay the symptoms after the symptom appear." The brain of a Fragile X Child is like an inattentive gardener, letting too many bushy spines grow on brain cells. Normal brains prune these spines to keep the cells' connections strong. The abundance of weak connections in Fragile X causes a kind of static in brain signals. At MIT's Picower Institute for Memory and Learning, Hayashi worked with mice that had the opposite problem of Fragile X: too little spine growths on neurons due to inactivity of a chemical in the brain called PAK. The PAK enzyme controls the growth of neurons in the brain. She decided to breed these mice with Fragile X mice to see if some of the offspring would have normal brains. But Fragile X affects the brain as it grows, and the PAK inhibitor doesn't activate until the mice are several weeks old. Meaning that for it to work, it would have to reverse structural abnormalities in the brain, something that has never been observed. © ScienCentral, 2000-2007.

Keyword: Development of the Brain
Link ID: 10487 - Posted: 06.24.2010

By Benjamin Lester Monkeys imitate what they see, but so do humans, only more discreetly. Whether any muscles actually flex, our brains fire up the same pathways needed to perform any action we observe another person perform. But new work on disabled volunteers indicates that the brain instead activates alternate circuits when faced with an action its body cannot physically copy. The research suggests that the brain's motor system may be wired to work toward a goal rather than just duplicating a movement. Every time you watch someone press a computer key or pick up a cup, regions of your brain unconsciously respond, mapping what you see onto the motor pathways you would use to carry out that same motion. Researchers believe that this so-called mirror neuron system, which consists of a subclass of motor neurons, is critical to learning new behaviors, and perhaps for developing skills like recognizing facial expressions. But neuroscientists have long wondered how the brain reacts if the body lacks the ability to replicate the action. In a study reported 12 July in Current Biology, a team from the Netherlands, Italy, and France showed videos of hands performing simple actions, like grasping a cup, to 16 "normal" people and two aplasic people born without hands or arms. While the volunteers watched the video, the researchers spied on their brain activity using MRI. © 2007 American Association for the Advancement of Science

Keyword: Brain imaging
Link ID: 10486 - Posted: 06.24.2010

Larry O'Hanlon, Discovery News — Giving a squirrel a big, sweet cookie can be a kind gesture, and now scientists have found it also encourages the critter to watch for predators. The conclusion, in a newly published study, has implications for other species, including the survival of those facing human-caused changes to their habitats. Most animals have two daily concerns: Getting food and not becoming food. Unfortunately, concentrating on one of those activities is almost always at the cost of the other. "These two things make you survive," said animal behavior researcher Joanna Makowska at the University of British Columbia and lead author of a paper on an experiment that revealed how squirrels juggle those needs in the July issue of Animal Behaviour. "Most animals can’t be very vigilant while eating," Makowska told Discovery News. To get a clearer picture of just how and when squirrels choose to focus on food or predators, she and her undergraduate professor at McGill University, Donald Kramer, created an experiment that put the squirrels to the test. They placed sunflower seeds inside a two-and-a-half-foot high frame that blocked their peripheral views of the urban park in which they lived. © 2007 Discovery Communications

Keyword: Attention
Link ID: 10485 - Posted: 06.24.2010

Brian Vastag Call it a flimsy silver lining to a noxious blue cloud: Long-term smokers have half the risk of Parkinson's disease that nonsmokers do, according to a new report. In 12,000 people studied, those who smoked the most—the equivalent of at least a pack a day for 60 years—had the lowest risk. And after smokers stubbed out their last butts, the protective effect faded. Cigarette, cigar, and pipe smoking appear to offer similar anti-Parkinson's benefits, according to the report in the July Archives of Neurology. Author Beate Ritz of the University of California, Los Angeles characterizes the amount of Parkinson's protection provided by smoking as moderate. "Never-smokers have about a twofold higher risk of Parkinson's disease than ever-smokers," she says. However, because Parkinson's disease is fairly rare—only about 60,000 new cases are diagnosed each year in the United States—and because smoking causes cancer and heart disease, "nobody would ever recommend smoking in order to prevent Parkinson's," Ritz emphasizes. ©2007 Science Service.

Keyword: Parkinsons; Drug Abuse
Link ID: 10484 - Posted: 06.24.2010

Kerri Smith People can will themselves to forget traumatic or emotional scenes, researchers have found. When the brain conducts such deletions, brain regions that process vision and emotion go quiet. Knowing that memories can be consciously suppressed, and the brain areas involved, could point to therapies for people who struggle to forget traumatic experiences, such as those with post-traumatic stress disorder or obsessive-compulsive disorder. Neuroscientist Brendan Depue, of the University of Colorado at Boulder, wanted to find out what goes wrong in the brains of sufferers of such conditions. Previous studies have shown that people can suppress memories of words. But to make the test relevant to traumatic memories, Depue's team included an emotional component. They showed volunteers pairs of pictures: one of a face, and one to evoke an emotional response — a car crash, or a wounded person. Once the subjects had learned to associate the image pairs, they were shown the faces alone, and either told to think of the associated picture or to try not to think about it. The subjects' brains were less active when they deliberately tried not to think of the associated picture, the team found. "It looks like these areas of the brain are being shut down," says Depue. ©2007 Nature Publishing Group

Keyword: Learning & Memory
Link ID: 10483 - Posted: 06.24.2010

Biomedical researcher Priti Kumar came to the United States to look for a cure for deadly encephalitis infections, which kill tens of thousands of people a year in her native India. She and her colleagues in the lab of Manjunath N. Swamy at Harvard's CBR Institute ended up finding a way to potentially treat virtually any brain disease. West Nile Virus encephalitis and Eastern Equine Encephalitis are among the many types of mosquito-spread encephalitis viruses that attack the brain. "There are no drugs existing for encephalitis in the world today," Kumar says. "What has been routinely commonly followed in all hospitals is that when a patient comes in with encephalitis, he is just put on something like supportive therapy and you wait for the immune system to kick back in, and the patient recovers if an immune system reaction to the virus is able to bring him out of the infection." Kumar's team was able to use RNA interference to develop a new kind of therapy against brain diseases like encephalitis. But there was still a big barrier to being able to use the drug in people-- the natural barrier called the blood-brain barrier, tightly-packed cells around the blood vessels that prevent molecules from passing from the bloodstream into the brain. © ScienCentral, 2000-2007.

Keyword: Miscellaneous
Link ID: 10482 - Posted: 06.24.2010

Being the life and soul of the party may cut your chances of a fatal heart or stroke, research suggests. A 30-year study by Chicago Northwestern University suggested shy or antisocial men were 50% more likely to die this way, compared with outgoing men. The Annals of Epidemiology study supports other work suggesting a link between personality and health. A British expert said lower social status may be the root cause of both shyness and poor health. The researchers tracked the health of more than 2,000 middle-aged men over three decades, until 60% of their subjects had died. The death certificates were matched with psychological questionnaires filled in at the start of the study to reveal the personality type of the man in question. The shyest group of men were 50% more likely to have died from heart attack or stroke than the group of most sociable men. When other information about the mens' lifestyles was analysed, no link to other known risk factors, such as smoking, drinking or obesity came to light - apparently ruling out the theory that shy or unsocial men might be dying because of unhealthy, couch potato behaviour. The researchers suggested that either that shy men are more stressed by new situations, or that the setting of their personality type is in some way linked to the part of the the brain that controls the smooth operation of the heart. Decades of research suggest there is only one personality type which is not linked to an increase risk of serious disease. Easy going people - so-called type "B" personalities - appear to be the healthiest. Type "A" personalities - driven workaholics prone to stress and anger, are more likely to suffer high blood pressure and heart disease, while Type "C" people, who suppress their feelings, have been connected to an increased risk of cancer.

Keyword: Stress; Emotions
Link ID: 10481 - Posted: 07.14.2007

By Jeanna Bryner The jury is still out on why the chicken crossed the road. But new research reveals an inbuilt magnetic compass guides domestic chickens when they do venture across the asphalt and other surfaces. Many animals have an innate sense of direction, finding their way along migration routes that extend thousands of miles. Often, they detect Earth’s magnetic field and use that for orientation. The new study focuses on birds. Study leader Wolfgang Wiltschko of Frankfurt University had been the first to show that migrating European robins rely on the Earth’s magnetic field to navigate during migrations. That finding came more than 40 years ago, and since then a similar magnetic compass has been found in more than 20 bird species, mostly songbirds. Most recently, Wiltschko and his colleagues found domestic chickens are equipped with magnetic sensors that work like compasses. They trained newly hatched chicks of domestic chickens to associate a red ball with their “mother.” At each corner of a pen (where the chicks were kept), designed to correspond to a magnetic North, South, East and West grid, they placed a white screen. Then they hid the ball behind one of the four screens and taught the chicks that the red-ball mother was always behind the screen in the magnetic North corner. © 2007 MSNBC.com © 2007 Microsoft

Keyword: Animal Migration
Link ID: 10480 - Posted: 06.24.2010

From The Economist print edition PSYCHOLOGISTS have known for a long time that economists are wrong. Most economists—at least, those of the classical persuasion—believe that any financial gain, however small, is worth having. But psychologists know this is not true. They know because of the ultimatum game, the outcome of which is often the rejection of free money. In this game, one player divides a pot of money between himself and another. The other then chooses whether to accept the offer. If he rejects it, neither player benefits. And despite the instincts of classical economics, a stingy offer (one that is less than about a quarter of the total) is, indeed, usually rejected. The question is, why? One explanation of the rejectionist strategy is that human psychology is adapted for repeated interactions rather than one-off trades. In this case, taking a tough, if self-sacrificial, line at the beginning pays dividends in future rounds of the game. Rejecting a stingy offer in a one-off game is thus just a single move in a larger strategy. And indeed, when one-off ultimatum games are played by trained economists, who know all this, they do tend to accept stingy offers more often than other people would. But even they have their limits. To throw some light on why those limits exist, Terence Burnham of Harvard University recently gathered a group of students of microeconomics and asked them to play the ultimatum game. All of the students he recruited were men. © The Economist Newspaper Limited 2007

Keyword: Hormones & Behavior; Emotions
Link ID: 10479 - Posted: 06.24.2010

By MICHAEL D. LEMONICK I was driving up the Massachusetts Turnpike one evening last February when I knocked over a bottle of water. I grabbed for it, swerved inadvertently--and a few seconds later found myself blinking into the flashlight beam of a state trooper. "How much have you had to drink tonight, sir?" he demanded. Before I could help myself, I blurted out an answer that was surely a new one to him. "I haven't had a drink," I said indignantly, "since 1981." It was both perfectly true and very pertinent to the trip I was making. By the time I reached my late 20s, I'd poured down as much alcohol as normal people consume in a lifetime and plenty of drugs--mostly pot--as well. I was, by any reasonable measure, an active alcoholic. Fortunately, with a lot of help, I was able to stop. And now I was on my way to McLean Hospital in Belmont, Mass., to have my brain scanned in a functional magnetic-resonance imager (fMRI). The idea was to see what the inside of my head looked like after more than a quarter-century on the wagon. Back when I stopped drinking, such an experiment would have been unimaginable. At the time, the medical establishment had come to accept the idea that alcoholism was a disease rather than a moral failing; the American Medical Association (AMA) had said so in 1950. But while it had all the hallmarks of other diseases, including specific symptoms and a predictable course, leading to disability or even death, alcoholism was different. Its physical basis was a complete mystery--and since nobody forced alcoholics to drink, it was still seen, no matter what the AMA said, as somehow voluntary. © 2007 Time Inc.

Keyword: Drug Abuse
Link ID: 10478 - Posted: 06.24.2010

Michael Hopkin Researchers have identified a cellular switch that triggers the production of 'good' fat cells, which pump out heat and raise the body's metabolic rate. The discovery, made in mice, might one day provide a way to treat or prevent obesity in humans. In adult humans, nearly all fat tissue is made of white fat cells, which store excess energy for later use. But brown fat cells have a high metabolic rate and burn up the chemical fuel, rather than store it. A higher proportion of babies' fat is brown, probably as a way to keep warm. But these deposits are mostly lost after infancy. Researchers led by Bruce Spiegelman at the Dana-Farber Cancer Institute in Boston, Massachusetts, have now identified the protein that induces developing fat cells to become brown, not white. The next step, he says, is to find drugs that can manipulate this process in adults. Spiegelman's team found that brown fat cells in mice contain large amounts of a protein called PRDM16, which is rare in white fat cells and other cells such as muscle and liver. ©2007 Nature Publishing Group

Keyword: Obesity
Link ID: 10477 - Posted: 06.24.2010

By BARRON H. LERNER, M.D. When I was growing up, the word “willpower” was used a lot. If only one was strong enough to resist sweets, according to logic of the time, one could stay thin. Yet today, based on a series of scientific discoveries, the importance of willpower in promoting weight loss is becoming an obsolete notion. Is it worth saving? The concept of willpower came less from scientific data than from Christian teachings about the dangers of temptation. Gluttony, after all, was one of the seven deadly sins, up there with pride, greed, extravagance, envy, wrath and sloth. The late 19th century was perhaps the heyday of the revolt against what John C. Burnham, a historian at Ohio State University, calls “bad habits.” Groups like the Salvation Army and the Women’s Christian Temperance Union urged sinners to stop drinking, gambling and smoking. Comparable sentiments characterized writings about obesity. In 1946, Wilson G. Smillie, a public health professor at Cornell, wrote that the physician should appeal to the obese patient’s “ability to manifest self-control.” Weight-loss programs like Overeaters Anonymous and Weight Watchers have reflected this philosophy. Copyright 2007 The New York Times Company

Keyword: Obesity
Link ID: 10476 - Posted: 06.24.2010

By AMANDA SCHAFFER Mary O’Regan more or less ignored her left arm for 20 years. As a sophomore in college, in 1986, she fell off the back of a friend’s dirt bike and hit her head on concrete, later suffering a stroke. After intensive medical and physical therapy, she learned to speak and walk again. She went back to school and then to work. (And, as it happened, two of her brothers ended up marrying two of the nurses who had taken care of her.) Still, much of her left side remained numb, and she did not regain use of her left arm. Last year, however, Ms. O’Regan, now 40 and living in Westwood, Mass., enrolled in a clinical trial for a new robotic device called the Myomo e100, designed to help stroke patients regain motion in their arms. The device, worn as an arm brace, works by sensing weak electrical activity in patients’ arm muscles and providing just enough assistance that they can complete simple exercises, like lifting boxes or flipping on light switches. By practicing such tasks, patients may begin to relearn how to extend and flex the arm, rebuilding and strengthening neurological pathways in the process. “The device is designed to help get patients over a functional hump” so they can start moving the weakened arm again, said John McBean, a mechanical engineer who developed the technology with Kailas Narendran, an electrical engineer and computer scientist. (The two began the project in 2002, in a graduate robotics class at M.I.T.) Copyright 2007 The New York Times Company

Keyword: Stroke; Robotics
Link ID: 10475 - Posted: 06.24.2010

By Laura Zigman Everyone has a moment in time that divides his or her life into "before" and "after." For me that moment was 10 years ago, when I was 34. I had just left New York and moved to Washington -- trading my soul-deadening career and size-0 studio apartment for a 9-to-5 job and a big one-bedroom overlooking Rock Creek Park and the zoo, trading my no-life life for an actual life, not to put too fine a point on it, and feeling really good about it -- when depression struck. Again. The way it had repeatedly since second grade. It was then that I finally realized that I would never be able to outrun myself; wherever I went, wherever I moved, however stealthily I tried to sneak away, I would always bring myself with me. And at the thought of that -- at the thought of a life sentence with chronic clinical depression as my cellmate and no chance of parole -- I finally knew the jig was up. Uncle, I cried at long last. Give me the meds. Describing what depression feels like is a little like trying to describe what chocolate tastes like or what classical music sounds like or what red looks like. But for me, being depressed was like being inside a sealed glass box right in the middle of a big huge party: I could see out and people could see in, but that's about as far as it went. © 2007 The Washington Post Company

Keyword: Depression
Link ID: 10474 - Posted: 06.24.2010