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'Language Gene' Has a Partner

Few genes have made the headlines as much as FOXP2. The first gene associated with language disorders , it was later implicated in the evolution of human speech. Girls make more of the FOXP2 protein, which may help explain their precociousness in learning to talk. Now, neuroscientists have figured out how one of its molecular partners helps Foxp2 exert its effects.

The findings may eventually lead to new therapies for inherited speech disorders, says Richard Huganir, the neurobiologist at Johns Hopkins University School of Medicine in Baltimore, Maryland, who led the work. Foxp2 controls the activity of a gene called Srpx2, he notes, which helps some of the brain's nerve cells beef up their connections to other nerve cells. By establishing what SRPX2 does, researchers can look for defective copies of it in people suffering from problems talking or learning to talk.

Until 2001, scientists were not sure how genes influenced language. Then Simon Fisher, a neurogeneticist now at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands, and his colleagues fingered FOXP2 as the culprit in a family with several members who had trouble with pronunciation, putting words together, and understanding speech. These people cannot move their tongue and lips precisely enough to talk clearly, so even family members often can?t figure out what they are saying. It “opened a molecular window on the neural basis of speech and language,” Fisher says.

Photo credit: Yoichi Araki, Ph.D.


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by Bethany Brookshire Most of us wish we ate better. I know I certainly do. But when hunger strikes, and you’re standing in line at the grab-and-go food joint, that salad seems really lackluster sitting next to that tasty-looking cookie. I can’t help but think that my diet — and my waistline — would look a lot better if I just craved lettuce a little more. Now a new study shows that although we may never cease to love cookies, we might be able to make that carrot a little more appealing. In overweight people, a behavioral intervention was associated with changes in how their brains responded to high- and low-calorie foods. The small pilot study is intriguing, but with just 13 participants, a larger study is needed before scientists will know if training the brain can make us abstain. “Everyone responds more strongly to high-calorie foods than low-calorie foods. It’s just normal,” says study coauthor Susan Roberts, a behavioral nutrition scientist from Tufts University in Medford, Mass. While most people prefer brownies over beets, people who are overweight or obese have a harder time avoiding high-calorie foods, she says. “When someone becomes overweight, there’s a dampening effect on a number of brain structures, including the reward system,” she says. “It’s harder to enjoy food generally, and so when someone becomes overweight, they really want to eat those high-calorie foods, because those are the foods that activate reward systems to the biggest extent.” Craving is a particular issue. Craving is distinct from hunger and focuses on a particular food, often foods that are high calorie. Other studies show that people who are obese have more cravings than those who are not. © Society for Science & the Public 2000 - 2014

Keyword: Obesity; Aggression
Link ID: 20086 - Posted: 09.17.2014

|By Daniel A. Yudkin If you’re reading this at a desk, do me a favor. Grab a pen or pencil and hold the end between your teeth so it doesn’t touch your lips. As you read on, stay that way—science suggests you’ll find this article more amusing if you do. Why? Notice that holding a pencil in this manner puts your face in the shape of a smile. And research in psychology says that the things we do—smiling at a joke, giving a gift to a friend, or even running from a bear—influence how we feel. This idea—that actions affect feelings—runs counter to how we generally think about our emotions. Ask average folks how emotions work—about the causal relationship between feelings and behavior—and they’ll say we smile because we’re happy, we run because we’re afraid. But work by such psychologists as Fritz Strack, Antonio Damasio, Joe LeDoux shows the truth is often the reverse: what we feel is actually the product, not the cause, of what we do. It’s called “somatic feedback.” Only after we act do we deduce, by seeing what we just did, how we feel. This bodes well, at first blush, for anyone trying to change their emotions for the better. All you’d need to do is act like the kind of person you want to be, and that’s who you’ll become. (Call it the Bobby McFerrin philosophy: “Aren’t happy? Don’t worry. Just smile!”) But new research, published in the Journal of Experimental Social Psychology by Aparna Labroo, Anirban Mukhopadhyay, and Ping Dong suggests there may be limits to our ability to proactively manage our own well-being. The team ran a series of studies examining whether more smiling led to more happiness. One asked people how much smiling they had done that day, and how happy they currently felt. Other studies manipulated the amount of smiling people actually did, either by showing them a series of funny pictures or by replicating a version of the pencil-holding experiment. As expected, across these experiments, the researchers found that the more people smiled, the happier they reported being. © 2014 Scientific American

Keyword: Emotions
Link ID: 20085 - Posted: 09.17.2014

By Douglas Main Researchers have created a blood test that they have used to accurately diagnose depression in a small sample of people, and they hope that with time and funding it could be used on a widespread basis. It is the first blood test—and thus the first “objective” gauge—for any type of mental disorder in adults, says study co-author Eva Redei, a neuroscientist at Northwestern University in Evanston, Ill. Outside experts caution, however, that the results are preliminary, and not close to ready for use the doctor’s office. Meanwhile, diagnosing depression the “old-fashioned way” through an interview works quite well, and should only take 10 to 15 minutes, says Todd Essig, a clinical psychologist in New York. But many doctors are increasingly overburdened and often not reimbursed for taking the time to talk to their patients, he says. The test works by measuring blood levels of nine different types of RNA, a chemical that the body uses to process DNA. Besides accurately diagnosing depression, which affects perhaps 10 percent of American adults and is becoming more common, the technique may also be able to tell who could benefit from talk therapy and who may be vulnerable to the condition in the first place. In a study describing the test, published in the journal Translational Psychiatry, the scientists recruited 32 patients who were diagnosed with depression using a clinical interview, the standard technique. They also got 32 non-depressed patients to participate as a control group. © 2014 Newsweek LLC

Keyword: Depression
Link ID: 20084 - Posted: 09.17.2014

By Megan Allison Diagnoses of Attention Hyperactivity Disorder are on the rise. The Centers for Disease Control and Prevention calculated that by 2011, 11 percent of children had been diagnosed with ADHD, and 6.1 percent of all US children were taking an ADHD medication. But could a solution be as simple as exercise? A study published this month in the Journal of Abnormal Child Psychology found that aerobic activity sessions before school helped children with ADHD with their moods and attention spans. The study involved a group of just over 200 students in kindergarten through second grade at schools in Indiana and Vermont. For 12 weeks, the students did 31 minutes of physical activity. The control group participated in classroom activities during this time. Although the results showed that all students showed improvement, authors noted that the exercise especially helped kids with ADHD. “It benefits all the kids, but I definitely see where it helps the kids with ADHD a lot,” said Jill Fritz, a fourth-grade teacher in Jacksonville, Fla. in an interview with The Wall Street Journal. “It really helps them get back on track and get focused.” In the Boston area, Dr. Sarah Sparrow Benes, Program Director of Physical and Health Education Programs at Boston University, teaches elementary and special educators how to use movement as a strategy in their classroom for learning. She finds that all students can benefit from exercise.

Keyword: ADHD; Aggression
Link ID: 20083 - Posted: 09.17.2014

By Neuroskeptic Today, we are thinking – and talking – about the brain more than ever before. It is widely said that neuroscience has much to teach psychiatry, cognitive science, economics, and others. Practical applications of brain science are proposed in the fields of politics, law enforcement and education. The brain is everywhere. This “Neuro Turn” has, however, not always been accompanied by a critical attitude. We ought to be skeptical of any claims regarding the brain because it remains a mystery – we fundamentally do not understand how it works. Yet much neuro-discourse seems to make the assumption that the brain is almost a solved problem already. For example, media stories about neuroscience commonly contain simplistic misunderstandings – such as the tendency to over-interpret neural activation patterns as practical guides to human behavior. For instance, recently we have heard claims that because fMRI finds differences in the brain activity of some violent offenders, this means that their criminal tendencies are innate and unchangeable – with clear implications for rehabilitation. Neuroscientists are well aware of the faults in lay discourse about the brain – and are increasingly challenging them e.g. on social media. Unfortunately, the same misunderstandings also exist within neuroscience itself. For example, I argue, much of cognitive neuroscience is actually based on (or, only makes sense given the assumption that) the popular misunderstanding that brain activity has a psychological ‘meaning’. In fact, we just do not know what a given difference in brain activity means, in the vast majority of cases. Thus, many research studies based on finding differences in fMRI activity maps across groups or across conditions, are not really helping us to understand the brain at all – but only providing us with a canvas to project our misunderstandings onto it.

Keyword: Brain imaging
Link ID: 20082 - Posted: 09.17.2014

By Elizabeth Pennisi "What's for dinner?" The words roll off the tongue without even thinking about it—for adults, at least. But how do humans learn to speak as children? Now, a new study in mice shows how a gene, called FOXP2, implicated in a language disorder may have changed between humans and chimps to make learning to speak possible—or at least a little easier. As a uniquely human trait, language has long baffled evolutionary biologists. Not until FOXP2 was linked to a genetic disorder that caused problems in forming words could they even begin to study language’s roots in our genes. Soon after that discovery, a team at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, discovered that just two bases, the letters that make up DNA, distinguished the human and chimp versions of FOXP2. To try to determine how those changes influenced the gene's function, that group put the human version of the gene in mice. In 2009, they observed that these "humanized" mice produced more frequent and complex alarm calls, suggesting the human mutations may have been involved in the evolution of more complex speech. Another study showed that humanized mice have different activity in the part of the brain called the striatum, which is involved in learning, among other tasks. But the details of how the human FOXP2 mutations might affect real-world learning remained murky. To solve the mystery, the Max Planck researchers sent graduate student Christiane Schreiweis to work with Ann Graybiel, a neuroscientist at the Massachusetts Institute of Technology in Cambridge. She's an expert in testing mouse smarts by seeing how quickly they can learn to find rewards in mazes. © 2014 American Association for the Advancement of Science

Keyword: Learning & Memory; Aggression
Link ID: 20081 - Posted: 09.16.2014

Ewen Callaway A dozen volunteers watched Alfred Hitchcock for science while lying motionless in a magnetic-resonance scanner. Another participant, a man who has lived in a vegetative state for 16 years, showed brain activity remarkably similar to that of the healthy volunteers — suggesting that plot structure had an impact on him. The study is published in this week's Proceedings of the National Academy of Sciences1. The film, an 1961 episode of the TV show Alfred Hitchcock Presents that had been condensed down to 8 minutes, is a study in suspense. In it, a 5-year-old totes a partially loaded revolver — which she thinks is a toy — around her suburban neighbourhood, shouting “bang” each time she aims at someone and squeezes the trigger. While the study participants watched the film, researchers monitored their brain activity by functional magnetic resonance imaging (fMRI). All 12 healthy participants showed similar patterns of activity, particularly in parts of the brain that have been linked to higher cognition (frontal and parietal regions) as well as in regions involved in processing sensory information (auditory and visual cortices). One behaviourally non-responsive person, a 20-year-old woman, showed patterns of brain activity only in sensory areas. But another person, a 34-year-old man who has been in a vegetative state since he was 18, had patterns of brain activity in the executive and sensory brain areas, similarly to that of the healthy subjects. “It was actually indistinguishable from a healthy participant watching the movie,” says Adrian Owen, a neuroscientist at the University of Western Ontario in London, Canada (see: 'Neuroscience: The mind reader'). © 2014 Nature Publishing Group

Keyword: Consciousness
Link ID: 20080 - Posted: 09.16.2014

By Linda Searing THE QUESTION Benzodiazepines such as Valium, Xanax and Ativan, widely prescribed to relieve anxiety and alleviate insomnia, are known to affect memory and cognition in the short term. Might they also have a more serious, longer-term effect on the brain? THIS STUDY analyzed data on 8,990 adults older than 66, including 1,796 with Alzheimer’s disease. In a five-to-10-year span before the start of the study, 3,767 of the participants (52 percent) had taken benzodiazepines. Overall, those who had taken the drugs were 51 percent more likely to have Alzheimer’s than were those who had never taken benzodiazepines. The longer people took the drugs, the greater their risk for Alzheimer’s. Those who took the drugs for less than 90 days had essentially the same risk as those who never took them. But risk nearly doubled for people who took them for longer than six months. Risk also was greater for longer-acting vs. shorter-acting benzodiazepines. WHO MAY BE AFFECTED? Adults, especially older people, who take benzodiazepines. The drugs have a calming effect on the body and work quickly, unlike antidepressants, which can take weeks to have an effect. The American Geriatrics Society lists benzodiazepines as inappropriate for treating older people for insomnia or agitation because of their negative effect on cognition seen in that age group and an increased likelihood of falls and accidents. However, some recent estimates note that roughly half of older adults take benzodiazepines. CAVEATS Some study participants may have been prescribed benzodiazepines to treat early symptoms of unrecognized dementia, which can include depression, anxiety and sleep disorders; the study authors noted that use of the drugs “might be an early marker of a condition associated with an increased risk of dementia and not the cause.”

Keyword: Alzheimers; Aggression
Link ID: 20079 - Posted: 09.16.2014

By ANDREW POLLACK New York State’s attorney general filed an antitrust lawsuit on Monday seeking to stop a pharmaceutical company from forcing patients with Alzheimer’s disease to switch to a new version of a widely used drug. The lawsuit contends that the switch is designed to blunt competition from low-priced generic versions of the medication. Forest Laboratories, now owned by Actavis, announced in February that it would stop selling the existing tablet form of the drug, Namenda, in favor of new extended-release capsules called Namenda XR that can be taken once a day instead of twice. While the company said that patients preferred the newer drug, it has made little secret of its desire to switch all patients to the newer form, which has a longer patent life, before the old tablets face generic competition in July. The strategy would make it much harder for the generics to gain traction. The lawsuit, filed in Federal District Court in Manhattan, says the step is an illegal attempt by Forest to maintain its monopoly even after its patent expires. “A drug company manipulating vulnerable patients and forcing physicians to alter treatment plans unnecessarily, simply to protect corporate profits, is unethical and illegal,” the attorney general, Eric T. Schneiderman, said in a statement. A spokesman for Actavis said the company did not comment on pending litigation as a matter of policy. The company said that the once-a-day drug had “significant advantages” for patients and their caregivers. The lawsuit argues that the benefit of switching is not very great. It says the company decided to force the switch because it feared that not enough patients would switch voluntarily. © 2014 The New York Times Company

Keyword: Alzheimers
Link ID: 20078 - Posted: 09.16.2014

By ANNA FELS THE idea of putting a mind-altering drug in the drinking water is the stuff of sci-fi, terrorist plots and totalitarian governments. Considering the outcry that occurred when putting fluoride in the water was first proposed, one can only imagine the furor that would ensue if such a thing were ever suggested. The debate, however, is moot. It’s a done deal. Mother Nature has already put a psychotropic drug in the drinking water, and that drug is lithium. Although this fact has been largely ignored for over half a century, it appears to have important medical implications. Lithium is a naturally occurring element, not a molecule like most medications, and it is present in the United States, depending on the geographic area, at concentrations that can range widely, from undetectable to around .170 milligrams per liter. This amount is less than a thousandth of the minimum daily dose given for bipolar disorders and for depression that doesn’t respond to antidepressants. Although it seems strange that the microscopic amounts of lithium found in groundwater could have any substantial medical impact, the more scientists look for such effects, the more they seem to discover. Evidence is slowly accumulating that relatively tiny doses of lithium can have beneficial effects. They appear to decrease suicide rates significantly and may even promote brain health and improve mood. Yet despite the studies demonstrating the benefits of relatively high natural lithium levels present in the drinking water of certain communities, few seem to be aware of its potential. Intermittently, stories appear in the scientific journals and media, but they seem to have little traction in the medical community or with the general public. The New York Times Company

Keyword: Depression
Link ID: 20077 - Posted: 09.15.2014

By Abby Phillip Most long-time, pack-a-day smokers who took part in a small study were able to quit smoking after six months, and researchers believe the hallucinogenic substance found in "magic mushrooms" could be the reason why. The study of the 15 participants, published this week in the Journal of Psychopharmacology, is the first to look at the feasibility of using the psychedelic drug psilocybin to aid in a smoking cessation treatment program. Existing treatments, from quitting cold turkey to prescription medications like Varenicline (Chantix), work for some people, but not the majority of smokers. With Varenicline, which mimics the effect of nicotine in the body, only about 35 percent of participants in a clinical trial were still abstaining from smoking six months later. Nearly half of all adult smokers reported that they tried to quit in 2010, according to the Centers for Disease Control and Prevention, yet 480,000 deaths are attributed to the addiction every year. Researchers at Johns Hopkins University recruited a group of long-time, heavy smokers — an average of 19 cigarettes a day for an average of 31 years — to participate in the study. They were treated with cognitive behavioral therapy for 15 weeks, and they were given a dose of the hallucinogen psilocybin at the five-week mark, when they had agreed to stop smoking. Although it was a small study, the results were promising. Twelve of the participants had quit smoking six months after being treated with the drug.

Keyword: Drug Abuse
Link ID: 20076 - Posted: 09.15.2014

by Michael Slezak It's one of the biggest mysteries of Alzheimer's. The disease is associated with the formation of protein plaques in the brain, but why is it that some people with plaques seem not to have the disease? Research suggests that some people's brains are able to reorganise during the early stages of Alzheimer's, delaying the appearance of initial symptoms. The plaques in question are small mounds of a protein called beta-amyloid, and are found in the brains of people with Alzheimer's disease. Whether these plaques are a cause of the disease has been hotly debated. One reason for doubt is the appearance of plaques in many older people who have no symptoms Movie Cameraof dementia at all. Using fMRI to measure changes in blood flow around the brain, William Jagust from the University of California in Berkley and colleagues compared brain function in three groups of people without symptoms of dementia: 22 young people, 16 older people with beta-amyloid plaques and 33 older people without the plaques. He asked each of them to memorise a photographed scene while inside the machine. Jagust found that older people with plaques had increased blood flow – which means stronger activation of that brain area – in the regions of the brain that are usually activated during memory formation, compared with the older people who did not have plaques. The team then analysed whether this extra brain activation might be helping to compensate for the plaques. © Copyright Reed Business Information Ltd.

Keyword: Alzheimers; Aggression
Link ID: 20075 - Posted: 09.15.2014

By Tara Parker-Pope The most reliable workers are those who get seven to eight hours of sleep each night, a new study shows. Researchers from Finland analyzed the sleep habits and missed work days among 3,760 men and women over about seven years. The workers ranged in age from 30 to 64 at the start of the study. The researchers found that the use of sick days was associated with the worker’s sleep habits. Not surprisingly, they found that people who did not get enough sleep because of insomnia or other sleep problems were more likely to miss work. But notably, getting a lot of extra sleep was also associated with missed work. The workers who were most likely to take extra sick days were those who slept five hours or less or 10 hours or more. Short sleepers and long sleepers missed about five to nine more days of work than so-called optimal sleepers, workers who managed seven to eight hours of sleep each night. The workers who used the fewest number of sick days were women who slept an average of 7 hours 38 minutes a night and men who slept an average of 7:46. The study results were published in the September issue of the medical journal Sleep. © 2014 The New York Times Company

Keyword: Sleep
Link ID: 20074 - Posted: 09.15.2014

By KEN BELSON The National Football League, which for years disputed evidence that its players had a high rate of severe brain damage, has stated in federal court documents that it expects nearly a third of retired players to develop long-term cognitive problems and that the conditions are likely to emerge at “notably younger ages” than in the general population. The findings are a result of data prepared by actuaries hired by the league and provided to the United States District Court judge presiding over the settlement between the N.F.L. and 5,000 former players who sued the league, alleging that it had hidden the dangers of concussions from them. “Thus, our assumptions result in prevalence rates by age group that are materially higher than those expected in the general population,” said the report, prepared by the Segal Group for the N.F.L. “Furthermore, the model forecasts that players will develop these diagnoses at notably younger ages than the generation population.” The statements are the league’s most unvarnished admission yet that the sport’s professional participants sustain severe brain injuries at far higher rates than the general population. They also appear to confirm what scientists have said for years: that playing football increases the risk of developing neurological conditions like chronic traumatic encephalopathy, a degenerative brain disease that can be identified only in an autopsy. “This statement clears up all the confusion and doubt manufactured over the years questioning the link between brain trauma and long-term neurological impairment,” said Chris Nowinski, the executive director of the Sports Legacy Institute, who has for many years pressured the league to acknowledge the connection between football and brain diseases. © 2014 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 20073 - Posted: 09.13.2014

by Bethany Brookshire Post-traumatic stress disorder, or PTSD, has many different symptoms. Patients may suffer from anxiety, flashbacks, memory problems and a host of other reactions to a traumatic event. But one symptom is especially common: 70 percent of civilian patients and 90 percent of combat veterans with PTSD just can’t get a decent night’s sleep. Problems with sleep, including rapid-eye movement — or REM — sleep, have long been associated with PTSD. “We know that sleep difficulties in the weeks following trauma predict the development of PTSD, and we know that bad sleep makes PTSD symptoms worse,” says Sean Drummond, a clinical psychologist who studies sleep at the University of California at San Diego. Studies in rats show that exposing the animals to traumatic, fearful experiences such as foot shocks disrupts their REM sleep. Drummond and his research assistant Anisa Marshall wanted to connect those findings to humans. But he soon found out that in humans, it’s not fear that predicts REM sleep. Instead, it’s safety. The scientists tested this in 42 people without PTSD using a measure called fear-potentiated startle. Subjects sit in a comfortable chair with an electrode on their wrists. A screen shows blue squares or yellow squares. If participants see blue squares, they run a high risk of receiving an annoying shock to the wrist. If they see yellow squares, they can relax; no shocks are headed their way. During this time, they will also hear random, loud bursts of white noise. The scientists measure how much the subjects startle in response to the noise by measuring the strength of their eyeblinks in response to the noise. In the presence of the blue squares, the blinks become much stronger, an effect called fear-potentiated startle. With yellow squares, the blinks weaken. © Society for Science & the Public 2000 - 2014.

Keyword: Stress; Aggression
Link ID: 20072 - Posted: 09.13.2014

by Michael Slezak "Cannabis catastrophic for young brains" screamed the headline on an Australian medical news website this week. The article, and others like it, were reporting on a study linking teenage cannabis use with school dropouts, addiction and suicide, published in the The Lancet Psychiatry. Echoing the research findings, the articles declared that if teenagers smoke cannabis daily, it makes them seven times more likely to commit suicide compared with non-users. Indeed, "there is no safe level of use", most reported. They also urged caution to legislators around the world that are gingerly taking steps towards weakening prohibition of cannabis, lest young people get easier access to it. So does smoking pot cause suicide? The Lancet authors say it probably does. Their study combined data from three previous longitudinal studies which together tracked cannabis use in more than 3000 people in Australia and New Zealand over many years. The authors looked for associations between the frequency of cannabis use before the age of 17 and outcomes, such as high school completion, until the people reached the age of 30. They found that those who smoked cannabis daily before they were 17 had lower odds of finishing high school and getting a degree than people who had never used cannabis. Larger increased odds were associated with cannabis dependence later in life, trying other illicit drugs and suicide attempts. But longitudinal studies only show correlation, not causation. The difficulty is that people take drugs for a reason, and that reason could be what's causing the outcome. In the case of school dropout, suicide and daily pot smoking, it is not hard to imagine what else could be going on in someone's life to engender these behaviours. © Copyright Reed Business Information Ltd

Keyword: Drug Abuse; Aggression
Link ID: 20071 - Posted: 09.13.2014

By Smitha Mundasad Health reporter, BBC News Giving young people Botox treatment may restrict their emotional growth, experts warn. Writing in the Journal of Aesthetic Nursing, clinicians say there is a growing trend for under-25s to seek the wrinkle-smoothing injections. But the research suggests "frozen faces" could stop young people from learning how to express emotions fully. A leading body of UK plastic surgeons says injecting teenagers for cosmetic reasons is "morally wrong". Botox and other versions of the toxin work by temporarily paralysing muscles in the upper face to reduce wrinkling when people frown. Nurse practitioner Helen Collier, who carried out the research, says reality TV shows and celebrity culture are driving young people to idealise the "inexpressive frozen face." But she points to a well-known psychological theory, the facial feedback hypothesis, that suggests adolescents learn how best to relate to people by mimicking their facial expressions. She says: "As a human being our ability to demonstrate a wide range of emotions is very dependent on facial expressions. "Emotions such as empathy and sympathy help us to survive and grow into confident and communicative adults." But she warns that a "growing generation of blank-faced" young people could be harming their ability to correctly convey their feelings. "If you wipe those expressions out, this might stunt their emotional and social development," she says. The research calls for practitioners to use assessment tools to decide whether there are clear clinical reasons for Botox treatment. BBC © 2014

Keyword: Emotions
Link ID: 20070 - Posted: 09.13.2014

By Jennifer Balmer Each summer, leatherback sea turtles (Dermochelys coriacea) migrate thousands of kilometers from their tropical breeding grounds to feed in cooler waters. Yet how the animals know when to begin their long journey back south at the end of the season has mostly remained a mystery. New findings, to be published in an upcoming issue of the Journal of Experimental Marine Biology and Ecology, suggest that leatherback sea turtles may be able to sense seasonal changes in sunlight by means of an unpigmented spot on the crown of their head—known as the pink spot (pictured). Researchers conducted an examination of the anatomical structures beneath the pink spot and found that the layers of bone and cartilage were remarkably thinner than in other areas of the skull. This thin region of the skull allows the passage of light through to an area of the brain, called the pineal gland, that acts as biological clock, regulating night-day cycles and seasonal patterns of behavior. The authors suggest that the lack of pigment in the crowning pink spot and thin skull region underlying it act as a “skylight,” allowing the turtles to sense the subtle changes in sunlight that accompany changing seasons, signaling them to return south when autumn approaches. © 2014 American Association for the Advancement of Science

Keyword: Animal Migration; Aggression
Link ID: 20069 - Posted: 09.13.2014

by Helen Thomson DON'T mind the gap. A woman has reached the age of 24 without anyone realising she was missing a large part of her brain. The case highlights just how adaptable the organ is. The discovery was made when the woman was admitted to the Chinese PLA General Hospital of Jinan Military Area Command in Shandong Province complaining of dizziness and nausea. She told doctors she'd had problems walking steadily for most of her life, and her mother reported that she hadn't walked until she was 7 and that her speech only became intelligible at the age of 6. Doctors did a CAT scan and immediately identified the source of the problem – her entire cerebellum was missing (see scan, below left). The space where it should be was empty of tissue. Instead it was filled with cerebrospinal fluid, which cushions the brain and provides defence against disease. The cerebellum – sometimes known as the "little brain" – is located underneath the two hemispheres. It looks different from the rest of the brain because it consists of much smaller and more compact folds of tissue. It represents about 10 per cent of the brain's total volume but contains 50 per cent of its neurons. Although it is not unheard of to have part of your brain missing, either congenitally or from surgery, the woman joins an elite club of just nine people who are known to have lived without their entire cerebellum. A detailed description of how the disorder affects a living adult is almost non-existent, say doctors from the Chinese hospital, because most people with the condition die at a young age and the problem is only discovered on autopsy (Brain, doi.org/vh7). © Copyright Reed Business Information Ltd.

Keyword: Brain imaging; Aggression
Link ID: 20068 - Posted: 09.12.2014

By Glendon Mellow University and scientific research center programs are increasingly finding it useful to employ artists and illustrators to help them see things in a new way. Few works of art from the Renaissance have been studied and pored over as meticulously as Michelangelo’s frescoes in the Sistine Chapel. Yet, the Master may still have some surprises hidden for an illustrator-scientist. Biomedical Illustrator Ian Suk (BSc, BMC) and Neurological Surgeon Rafael Tamargo (MD, FACS), both of Johns Hopkins proposed in a 2010 article in the journal Neurosurgery, that the panel above, Dividing Light from the Darkness by Michelangelo actually depicts the brain stem of God. Using a series of comparisons of the unusual shadows and contours on God’s neck to photos of actual brain stems, the evidence seems completely overwhelming that Michelangelo used his own limited anatomical studies to depict the brain stem. It’s unlikely even the educated members of Michelangelo’s audience would recognize it. I encourage you to look over the paper here, and enlarge the images in the slideshow: Suk and Tamargo are utterly convincing. Unlike R. Douglas Fields in this previous blog post from 2010 on Scientific American, I don’t think there’s room to believe this is a case of pareidolia. I imagine the thrill of feeling Michelangelo communicating directly with the authors across the centuries was immense. © 2014 Scientific American,

Keyword: Brain imaging
Link ID: 20067 - Posted: 09.12.2014