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By Christian Jarrett Christmas is over and the start of the movie awards season is only weeks away! This is my excuse for a post about cinema and the brain. Over the years I’ve been keeping note of actors who studied neuroscience and other similar factoids and now I have the chance to share them with you. So here, in no particular order, are 10 surprising links between the worlds of Hollywood and brain research: 1. Actress Mayim Bialik is a neuroscientist. Bialik currently plays the character of neuroscientist Amy Fowler in the Big Bang Theory, which is neat because Bialik herself has a PhD in neuroscience. Her PhD thesis, completed at UCLA in 2007, has the title: “Hypothalamic regulation in relation to maladaptive, obsessive-compulsive, affiliative, and satiety behaviors in Prader-Willi syndrome.” “I don’t try and rub my neuroscience brain in people’s face[s],” Bialik says, “but when we have lab scenes … I have had to say that’s not where the tectum would be, we need it down here … or I’ve actually carved the fourth ventricle into slices … ’cause you know, why not have me do it.” Among her other acting roles, Bialik also featured in the short film for Michael Jackson’s Liberian Girl and she played the child version of Bette Midler’s character in Beaches (1988). 2. Natalie Portman is a neuroscientist. Perform a Google Scholar search on her name and you won’t get very far. But under her original name of Natalie Hershlag, the Oscar-winning actress co-authored a paper in 2002 on the role of the frontal lobes in infants’ understanding of “object permanence” – recognizing that things still exist even when you can’t see them. According to the Mind Hacks blog, Ms. Portman contributed to this research while working as a research assistant at Harvard University. Her paper has now been cited in the literature over 100 times. © 2013 Condé Nast.

Keyword: Miscellaneous
Link ID: 19079 - Posted: 12.31.2013

For tobacco hornworms, bad breath might be the key to surviving the night. As their name suggests, these desert-dwelling caterpillars (larvae of the Manduca sexta moth) regularly chomp on nicotine-laced tobacco leaves. Scientists observed that caterpillars feeding on genetically modified, nicotine-free tobacco plants were more likely to disappear during the night than those chowing down on regular tobacco, leading them to suspect that the hornworms might be repurposing the toxic chemical to defend themselves against nocturnal predators like wolf spiders (Camptocosa parallela, pictured above feasting on a larva). The researchers investigated a gene called CYP6B46, which is active in the hornworm’s gut. Turning the gene off resulted in higher nicotine levels in the hornworms’ poop, suggesting that the gene helps the larvae avoid excreting the chemical by pumping it out of their guts and into their blood. The caterpillars had to be exuding the toxic nicotine somehow, so the scientists gave them an insect version of a breathalyzer test and discovered that they breathe it out with every exhale, the team reports online today in the Proceedings of the National Academy of Sciences. This “toxic halitosis” repelled wolf spiders, which actually flee from caterpillars with nicotine on their breath, as you can see in this video. Still, bad breath is no guarantee of a long life: It didn’t deter some of the hornworms’ other predators, including big-eyed bugs and antlion larvae. © 2013 American Association for the Advancement of Science

Keyword: Neurotoxins
Link ID: 19078 - Posted: 12.31.2013

By John Horgan New Year’s Day is approaching, a time when we—by which I mean I–brood over past failures and vow to improve ourselves: I will be less judgmental with my kids and more romantic with my girlfriend. I will stop binging on cookies and bad TV. (Why, oh why, do I keep watching Blacklist?) I will not assume that people who disagree with me are stupid or evil. Every time you choose one path over another, you are exercising your free will. Humanity has more freedom of choice now--and hence more free will--than in any previous era. At this time of year, I like to hearten my fellow Resolutionaries by defending the concept of free will, which has been attacked by various scientific pundits (who are just misguided, not stupid or evil). After all, how can you believe in resolutions unless you believe in free will? Below is an edited version of an essay that I originally wrote for The Chronicle of Higher Education. I never really thought about free will—or rather, I just took it for granted—until 1991, when I interviewed the late, great Francis Crick, who had switched from cracking the genetic code to solving the riddle of consciousness. With unnerving cheerfulness, Crick informed me that brain research is contradicting the notion of free will. Picking up a pen from his desk, he noted that even this simple act is underpinned and preceded by complex biochemical processes taking place below the level of consciousness. “What you’re aware of is a decision, but you’re not aware of what makes you do the decision,” Crick said. “It seems free to you, but it’s the result of things you’re not aware of.” I frowned, and Crick chuckled at my distress. © 2013 Scientific American,

Keyword: Consciousness
Link ID: 19077 - Posted: 12.28.2013

JoNel Aleccia NBC News Surgery to remove a brain tumor two years ago has left a 12-year-old Texas girl with a heartbreaking condition that makes her gain massive amounts of weight — even though her body thinks it’s starving. Doctors say a gastric bypass operation is the only thing that can help Alexis Shapiro, who is 4-foot-7 and weighs 198 pounds. But the U.S. military, which provides her family’s health insurance, says it won’t pay for the $50,000 weight-loss procedure because she’s too young. “Our reviewers have denied your request for Roux-En-Y Gastric Bypass,” reads the rejection notice sent this month. Alexis’ parents — and her doctor — are protesting the decision from insurer TRICARE, which they say sentences the child to a fate of dangerous health problems and social isolation caused by hypothalamic obesity, which is packing on at least 2 pounds every week. “It just keeps going up and up,” said her mother, Jenny Shapiro, 34, of Cibolo, Texas. “She desperately needs this. I feel like she will die if she does not get this surgery.” In just the past three months, Alexis was hospitalized for a kidney infection and developed Type 2 diabetes that requires nightly insulin injections, both related to her growing girth. Dr. Thomas H. Inge, a Cincinnati expert in pediatric obesity who is treating Alexis, acknowledged that there have been few cases like hers. But he said surgery may be the only way to stop weight gain that could top out at 400 pounds — and to cut the brain cravings that make Alexis want to eat an entire jar of peanut butter at one sitting.

Keyword: Obesity
Link ID: 19076 - Posted: 12.28.2013

Imagine this: Every day, you can feel people looking at you warily. They want to hurt you. Even the police are out to get you. You try to rid your mind of all the ill-intentioned people, but you can't ignore the other thing that is gnawing at you. Those bugs on your arm won't leave you alone, no matter how often you gouge at them. Such are the hallucinations and paranoia felt by those with a stimulant drug addiction. Sometimes the substance abuse is so severe it causes neurological damage and psychosis becomes a chronic condition. Combine untreated addiction with homelessness and physical health problems, and you get a health emergency. Vancouver police and the region's health authorities are desperately trying to figure out how to help the most vulnerable of mentally ill drug addicts. The province estimates that roughly 130,000 people in British Columbia suffer from a severe addiction and/or mental health illness. But police and emergency workers are increasingly dealing with a much smaller group of people whose brains have been damaged by their stimulant addiction and who appear to be responsible for random violent acts on Vancouver's streets. Dr. Nader Sharifi, addiction medicine lead with the Fraser Health Authority, said there are few good treatment options for those people. "It's a bit of a challenging question, because what we have available isn't necessarily structured for this patient sub-type. It's either structured for addiction, or structured for mental health illness, but not necessarily the two together." © CBC 2013

Keyword: Schizophrenia; Drug Abuse
Link ID: 19075 - Posted: 12.28.2013

By NICHOLAS BAKALAR Both acupuncture and sham acupuncture were effective in reducing menopausal symptoms in women being treated with aromatase inhibitors for breast cancer, a small randomized trial found. Joint and muscle pain, hot flashes and night sweats are common side effects of those estrogen-lowering drugs. The trial, published online in Cancer, randomized 47 breast cancer patients to eight weekly sessions of either real or sham acupuncture. Those assigned to real acupuncture received treatment with needles in recognized acupoints believed to be helpful in relieving menopausal symptoms. The controls got non-penetrating needles placed in sham acupuncture points. Patients and researchers did not know which patients had received which treatment. The patients kept daily diaries or filled out several questionnaires on the frequency and severity of hot flashes and other symptoms. Patient-reported symptoms, especially hot flashes, improved significantly after both sham and real treatment. There was no statistically significant difference between the two groups. The results may be attributable to a placebo effect, but the scientists suggest that the slight pricking of the skin could cause physiological changes. In any case, the lead author, Dr. Ting Bao, a medical oncologist at the University of Maryland, Baltimore, said there is no harm in trying acupuncture. “Acupuncture as a medical procedure has been practiced for thousands of years,” she said. “It has a minimal risk and potentially significant benefits.” Copyright 2013 The New York Times Company

Keyword: Pain & Touch
Link ID: 19074 - Posted: 12.28.2013

By Susana Martinez-Conde If you’re a bit lax with your post-holiday brushing, this little-known illusion may give you the incentive you need to keep those candy canes in check, or at least brush and floss afterwards. Vision scientist Robert O’Shea and his colleagues published a recent study in PLoS One showing that dentists can fall prey to a visual illusion of size and make larger holes in teeth than needed. The illusion fooling the dentists is a variant of a classical perceptual phenomenon known as the Delboeuf illusion, named after its creator, the Belgian natural philosopher, experimentalist, mathematician and hypnotist Joseph Remi Leopold Delboeuf. The scientists supplied 8 specialist dentists and endodontists, who served as experimental subjects, with a large pool of extracted teeth. The teeth contained holes, and the task of the dentists was to cut cavities in preparation for filling. Unknown to the dentists, each tooth presented a more or less powerful version of the Delboeuf illusion, making the holes appear smaller than their actual size. The results showed that the smaller the holes looked, the larger the cavities that the dentists made for later filling. The researchers recommend that dentists and other health practitioners receive training in “illusion awareness” (my words, not theirs), so that they may counteract these and related perceptual effects. © 2013 Scientific American,

Keyword: Vision
Link ID: 19073 - Posted: 12.28.2013

By CARL ZIMMER There are many things that make humans a unique species, but a couple stand out. One is our mind, the other our brain. The human mind can carry out cognitive tasks that other animals cannot, like using language, envisioning the distant future and inferring what other people are thinking. The human brain is exceptional, too. At three pounds, it is gigantic relative to our body size. Our closest living relatives, chimpanzees, have brains that are only a third as big. Scientists have long suspected that our big brain and powerful mind are intimately connected. Starting about three million years ago, fossils of our ancient relatives record a huge increase in brain size. Once that cranial growth was underway, our forerunners started leaving behind signs of increasingly sophisticated minds, like stone tools and cave paintings. But scientists have long struggled to understand how a simple increase in size could lead to the evolution of those faculties. Now, two Harvard neuroscientists, Randy L. Buckner and Fenna M. Krienen, have offered a powerful yet simple explanation. In our smaller-brained ancestors, the researchers argue, neurons were tightly tethered in a relatively simple pattern of connections. When our ancestors’ brains expanded, those tethers ripped apart, enabling our neurons to form new circuits. Dr. Buckner and Dr. Krienen call their idea the tether hypothesis, and present it in a paper in the December issue of the journal Trends in Cognitive Sciences. “I think it presents some pretty exciting ideas,” said Chet C. Sherwood, an expert on human brain evolution at George Washington University who was not involved in the research. Dr. Buckner and Dr. Krienen developed their hypothesis after making detailed maps of the connections in the human brain using f.M.R.I. scanners. When they compared their maps with those of other species’ brains, they saw some striking differences. © 2013 The New York Times Company

Keyword: Development of the Brain; Evolution
Link ID: 19072 - Posted: 12.27.2013

By JULIE CRESWELL RALEIGH, N.C. — As darkness fell on a Friday evening over downtown Raleigh, N.C., Michael Lyons, a paramedic supervisor for Wake County Emergency Medical Services, slowly approached the tall, lanky man who was swaying back and forth in a gentle rhythm. In answer to Mr. Lyons’s questions, the man, wearing a red shirt that dwarfed his thin frame, said he was bipolar, schizophrenic and homeless. He was looking for help because he did not think his prescribed medication was working. In the past, paramedics would have taken the man to the closest hospital emergency room — most likely the nearby WakeMed Health and Hospitals, one of the largest centers in the region. But instead, under a pilot program, paramedics ushered him through the doors of Holly Hill Hospital, a commercial psychiatric facility. “He doesn’t have a medical complaint, he’s just a mental health patient living on the street who is looking for some help,” said Mr. Lyons, pulling his van back into traffic. “The good news is that he’s not going to an E.R. That’s saving the hospital money and getting the patient to the most appropriate place for him,” he added. The experiment in Raleigh is being closely watched by other cities desperate to find a way to help mentally ill patients without admitting them to emergency rooms, where the cost of treatment is high — and unnecessary. While there is evidence that other types of health care costs might be declining slightly, the cost of emergency room care for the mentally ill shows no sign of ebbing. Nationally, more than 6.4 million visits to emergency rooms in 2010, or about 5 percent of total visits, involved patients whose primary diagnosis was a mental health condition or substance abuse. That is up 28 percent from just four years earlier, according to the latest figures available from the Agency for Healthcare Research and Quality in Rockville, Md. By one federal estimate, spending by general hospitals to care for these patients is expected to nearly double to $38.5 billion in 2014, from $20.3 billion in 2003. © 2013 The New York Times Company

Keyword: Schizophrenia
Link ID: 19071 - Posted: 12.27.2013

By KEN BELSON Revelations in recent years that thousands of former football players might have severe brain trauma from injuries sustained on the field have set off a rush in the medical community to seize the potentially lucrative market for assessing brain damage. But experts say claims regarding the validity of these assessments are premature and perhaps unfounded. Most researchers believe that C.T.E., or chronic traumatic encephalopathy, the degenerative brain disease found in dozens of former N.F.L. players, can be diagnosed only posthumously by analyzing brain tissue. Researchers at U.C.L.A. have developed a test they assert might identify the condition in a living person by injecting a compound that clings to proteins in the brain and later appears in a PET scan. But some are skeptical. “There has really been so much hype surrounding C.T.E., so there is a real need for making sure the public knows that this type of science moves slowly and must move very carefully,” said Robert Stern, a professor of neurology and neurosurgery at Boston University School of Medicine and a founder of the Center for the Study of Traumatic Encephalopathy. He is part of a group that is developing a different biomarker to identify tau, the protein that is a hallmark of C.T.E. “My fear is the people out there who are so much in need, scared for their lives and desperate for information, it might give them false hope,” he said. The debate over the scientific validity of such brain exams was highlighted recently when Tony Dorsett, a Hall of Fame running back for the Dallas Cowboys, and several other prominent former players said they were found to have C.T.E. after taking the experimental test developed by U.C.L.A. Dorsett, 59, told CNN that “they came to find out I have C.T.E.” and that his memory lapses, short temper and moodiness were “all because of C.T.E.” Despite what was widely reported as a diagnosis, the experimental test is perhaps years from gaining federal approval. An antidote is even more remote because C.T.E. is a degenerative condition with no known cure. That is why neurologists, researchers and bioethicists question whether the doctors at U.C.L.A. and at TauMark, the company with the exclusive license to commercialize the test, may leave some former players and their families with false hopes or undue worry. © 2013 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 19070 - Posted: 12.27.2013

By Sandra G. Boodman, Bebe Bahnsen remembers the night, alone in her small cottage on the Alabama coast, that she felt a strong urge to drink a can of drain cleaner. For years, antidepressants combined with talk therapy had enabled Bahnsen, whose first name is Beatrice, to function well, establishing a thriving public relations business in Washington followed by a career as a newspaper reporter. But those days had been supplanted by a prolonged suicidal depression that had proved impervious to electroshock treatments, periodic hospitalizations and a raft of psychiatric drugs. The phone call in which Bahnsen confided her desire to drink poison seemed to confirm the worst fears of one of her closest friends. “I figured, well, she was one of those people who just was not ever going to get better,” said Paddy Bowman, a folklore specialist who lives in Alexandria. Bahnsen, now 73, traces the beginning of her psychological slide to the mid-1990s, when she decided that, after two decades, she’d had enough of Washington. She moved back to her home state of Georgia and her life slowly began to unravel. She felt estranged from her large and devoted circle of friends, began having problems at work, and grew restless and increasingly depressed. “I felt as though I was on a large island and everyone was slowly moving away and I was there by myself,” Bahnsen recalled. For the first time in her life, she said, she was intermittently psychotic. Periodic suicide attempts, some involving overdoses of prescribed sleeping pills, landed her in a series of mental hospitals. In November 2006 she was hospitalized in Las Vegas, where she was then living with one of her sons. Doctors, baffled by her longstanding failure to improve, decided to take a closer look at her case. What they found resulted in an entirely different treatment, one that had a rapid and dramatic effect on her mental state. © 1996-2013 The Washington Post

Keyword: Depression; Alzheimers
Link ID: 19069 - Posted: 12.24.2013

By RICHARD A. FRIEDMAN, M.D. When will we ever get depression under control? Of all the major illnesses, mental or physical, depression has been one of the toughest to subdue. Despite the ubiquity of antidepressant drugs — there are now 26 to choose from — only a third of patients with major depression will experience a full remission after the first round of treatment, and successive treatments with different drugs will give some relief to just 20 to 25 percent more. About 30 percent of people with depression have some degree of treatment resistance. And the greater the degree of resistance, the more likely a future relapse, even if the patient continues taking the drug. Although we have learned much about depression — for example, the recent research showing that the successful treatment of insomnia in depressed patients essentially doubles their response to a drug like Prozac — we still don’t understand its fundamental cause. The old idea that the disease results from a deficiency of a single neurotransmitter like serotonin or dopamine is clearly simplistic and wrong. Maybe psychiatrists and neuroscientists have something to learn from the successful hunt for the Higgs boson. Of course a debilitating disease has nothing in common with a subatomic particle, except that both are mysterious and elusive. But it was those very qualities that inspired international teams of physicists to work together for years until they finally identified the boson last year. Among biomedical scientists, who compete for the same research dollars and want to be first across the finish line with an important finding, such cooperation is hardly the norm. But there are signs that this is changing. Not long ago, I sat in at a meeting of the Hope for Depression Research Foundation. Audrey Gruss, the knowledgeable and energetic philanthropist who started the foundation, has corralled a group of senior basic and clinical neuroscientists to look for solutions. (It is not the first to try a collaborative approach; others are being sponsored by the MacArthur Foundation and the Pritzker Consortium.) Copyright 2013 The New York Times Company

Keyword: Depression
Link ID: 19068 - Posted: 12.24.2013

By Regina Harrell and Pulse, I am a primary-care doctor who makes house calls in and around Tuscaloosa, Ala. Today my rounds start at a house located down a dirt road a few miles outside town. Gingerly, I cross the front walk; Mrs. Edgars told me that she killed a rattlesnake in her flowerbed last year. She is at the door, expecting my visit. Mr. Edgars sits on the couch, unable to recall that I am his doctor, or even that I am a doctor, but happy to see me nonetheless. We chat about the spring garden and the rain, then we move on to Mr. Edgars’s arthritis. Earlier on in his dementia, he wandered the woods, and his wife was afraid he would get lost and die, although the entire family agreed that this was how he would want it. Now, in a strange twist, his knee arthritis has worsened enough that it has curtailed his wanderings. I suspect that Mrs. Edgars is undertreating the pain to decrease the chance that he’ll wander off again. We talk about how anxious he grows whenever she’s out of his sight and how one of his children comes to sit with him so that she can run errands. She shows me a quilt remnant found in a log cabin on their property; it likely belonged to her husband’s grandfather, making the rough-edged fabric about a century old. I leave carrying a parting gift from her — a jar of homegrown pickled okra. When I get back to the office, I turn on the computer to write a progress note in Mr. Edgars’s electronic health record, or EHR. In addition to recording the details of our visit, I must try to meet the new federal criteria for “meaningful use,” criteria that have been adopted by my office with threats that I won’t get paid for my work if I don’t. © 1996-2013 The Washington Post

Keyword: Alzheimers
Link ID: 19067 - Posted: 12.24.2013

By Melissa Hogenboom Science reporter, BBC News An analysis of a Neanderthal's fossilised hyoid bone - a horseshoe-shaped structure in the neck - suggests the species had the ability to speak. This has been suspected since the 1989 discovery of a Neanderthal hyoid that looks just like a modern human's. But now computer modelling of how it works has shown this bone was also used in a very similar way. Writing in journal Plos One, scientists say its study is "highly suggestive" of complex speech in Neanderthals. The hyoid bone is crucial for speaking as it supports the root of the tongue. In non-human primates, it is not placed in the right position to vocalise like humans. An international team of researchers analysed a fossil Neanderthal throat bone using 3D x-ray imaging and mechanical modelling. This model allowed the group to see how the hyoid behaved in relation to the other surrounding bones. Stephen Wroe, from the University of New England, Armidale, NSW, Australia, said: "We would argue that this is a very significant step forward. It shows that the Kebara 2 hyoid doesn't just look like those of modern humans - it was used in a very similar way." He told BBC News that it not only changed our understanding of Neanderthals, but also of ourselves. "Many would argue that our capacity for speech and language is among the most fundamental of characteristics that make us human. If Neanderthals also had language then they were truly human, too." BBC © 2013

Keyword: Evolution; Language
Link ID: 19066 - Posted: 12.24.2013

Helen Shen The ability to erase memory may jump from the realm of film fantasy (such as Eternal Sunshine of the Spotless Mind, shown here) to reality. In the film Eternal Sunshine of the Spotless Mind, unhappy lovers undergo an experimental brain treatment to erase all memories of each other from their minds. No such fix exists for real-life couples, but researchers report today in Nature Neuroscience that a targeted medical intervention helps to reduce specific negative memories in patients who are depressed1. "This is one time I would say that science is better than art," says Karim Nader, a neuroscientist at McGill University in Montreal, Canada, who was not involved in the research. "It's a very clever study." The technique, called electroconvulsive (ECT) or electroshock therapy, induces seizures by passing current into the brain through electrode pads placed on the scalp. Despite its sometimes negative reputation, ECT is an effective last-resort treatment for severe depression, and is used today in combination with anaesthesia and muscle relaxants. Marijn Kroes, a neuroscientist at Radboud University Nijmegen in the Netherlands, and his colleagues found that by strategically timing ECT bursts, they could target and disrupt patients' memory of a disturbing episode. A matter of time The strategy relies on a theory called memory reconsolidation, which proposes that memories are taken out of 'mental storage' each time they are accessed and 're-written' over time back onto the brain's circuits. Results from animal studies and limited evidence in humans suggest that during reconsolidation, memories are vulnerable to alteration or even erasure2–4. © 2013 Nature Publishing Group

Keyword: Learning & Memory; Stress
Link ID: 19065 - Posted: 12.23.2013

By MICHAEL LUO and MIKE McINTIRE Last April, workers at Middlesex Hospital in Connecticut called the police to report that a psychiatric patient named Mark Russo had threatened to shoot his mother if officers tried to take the 18 rifles and shotguns he kept at her house. Mr. Russo, who was off his medication for paranoid schizophrenia, also talked about the recent elementary school massacre in Newtown and told a nurse that he “could take a chair and kill you or bash your head in between the eyes,” court records show. The police seized the firearms, as well as seven high-capacity magazines, but Mr. Russo, 55, was eventually allowed to return to the trailer in Middletown where he lives alone. In an interview there recently, he denied that he had schizophrenia but said he was taking his medication now — though only “the smallest dose,” because he is forced to. His hospitalization, he explained, stemmed from a misunderstanding: Seeking a message from God on whether to dissociate himself from his family, he had stabbed a basketball and waited for it to reinflate itself. When it did, he told relatives they would not be seeing him again, prompting them to call the police. As for his guns, Mr. Russo is scheduled to get them back in the spring, as mandated by Connecticut law. “I don’t think they ever should have been taken out of my house,” he said. “I plan to get all my guns and ammo and knives back in April.” The Russo case highlights a central, unresolved issue in the debate over balancing public safety and the Second Amendment right to bear arms: just how powerless law enforcement can be when it comes to keeping firearms out of the hands of people who are mentally ill. Connecticut’s law giving the police broad leeway to seize and hold guns for up to a year is actually relatively strict. Most states simply adhere to the federal standard, banning gun possession only after someone is involuntarily committed to a psychiatric facility or designated as mentally ill or incompetent after a court proceeding or other formal legal process. Relatively few with mental health issues, even serious ones, reach this point. © 2013 The New York Times Company

Keyword: Aggression; Schizophrenia
Link ID: 19064 - Posted: 12.23.2013

By Elijah Wolfson Of the many ills that can befall the human body, brain damage is one of the most devastating – and confusing. When a person suffers from a traumatic brain injury that leaves him or her in an uncommunicative state, doctors and loved ones face one of medical science’s most confounding questions: How do we know when a person is still there? When is a body just a body? Those question only get more complicated with the startling news that the brains of some patients in a vegetative state appear to recognize familiar faces. The implications are mind-boggling. Brain death – when there is zero brain function – is both a medical and legal term, and it is, quite literally, death. But when there is some brain function left, the lines blur rather quickly. A brain-damaged patient may live for months and even years, in limbo: her eyes may open and she may sleep and wake up in what appears to be a normal cycle, but she has no meaningful interactions and shows no awareness of her surroundings – or herself. She is in what the medical community calls a “persistent vegetative state,” awake but unaware. It’s unlikely that she will ever recover, and if she does, she will probably face severe physical and neurological impairments. Not what most of us call living. Someone in a vegetative state raises an essential moral and ethical question and an often bitter debate: How much should we do to keep a body on autopilot going? The debate has intensified in recent years, as a few studies have found striking examples of vegetative patients who seem to be able, on some level, to communicate. “With changing paradigms of imaging and other techniques,” Dr. Karen Hirsch, a neurologist and neurosurgeon at the Stanford University Medical Center, told Newsweek, “we are learning that maybe some of these people do have some awareness.” © 2013 IBT MEDIA INC

Keyword: Consciousness
Link ID: 19063 - Posted: 12.23.2013

By Alexandra Sifferlin It’s always been conventional wisdom that girls reach maturity more quickly than boys, but now scientists have provided some proof. In new research published in the journal Cerebral Cortex, an international group of researchers led by a team from Newcastle University in England found that girls’ brains march through the reorganization and pruning typical of normal brain development earlier than boys’ brains. In the study, in which 121 people between ages 4 to 40 were scanned using MRIs, the scientists documented the ebb and flow of new neural connections, and found that some brain fibers that bridged far-flung regions of the brain tended to remain stable, while shorter connections, many of which were redundant, were edited away. And the entire reorganization seemed to occur sooner in girls’ brains than in boys’ brains. Females also tended to have more connections across the two hemispheres of the brain. The researchers believe that the earlier reorganization in girls makes the brain work more efficiently, and therefore reach a more mature state for processing the environment. What drives the gender-based difference in timing isn’t clear from the current study, but the results suggest that may be a question worth investigating. © 2013 Time Inc.

Keyword: Development of the Brain; Sexual Behavior
Link ID: 19062 - Posted: 12.23.2013

By Gary Stix Is sleep good for everything? Scientists hate giving unqualified answers. But the more sleep researchers look, the more the answer seems to be tending toward a resounding affirmative. The slumbering brain plays an essential role in learning and memory, one of the findings that sleep researchers have reinforced repeatedly in recent years. But that’s not all. There’s a growing recognition that sleep appears to be involved in regulating basic metabolic processes and even in mental health. Robert Stickgold, a leading sleep researcher based at Harvard Medical School, gives a précis here of the current state of sommeil as it relates to memory, schizophrenia, depression, diabetes—and he even explains what naps are good for. How far have we come in understanding sleep? Although we understood the function of every other basic drive 2,000 years ago, we are still struggling to figure out what the biological functions of sleep are. One of the clearest messages now is that for every two hours humans spend awake during the day, the brain needs an hour offline to process the information it takes in and figure out what to save and what to dump and how to file and what it all means. So what is sleep for? Memories are processed during sleep. But sleep doesn’t have just one function. It’s a little bit like listening to tongue researchers arguing about whether the function of the tongue has to do with taste or speech. And you want to say: ‘Guys, c’mon, it’s both.’ There’s very good evidence now that sleep, besides helping memory, has a role in immune and endocrine functions. There’s a lot of talk about to what extent the obesity epidemic is actually a consequence of too little sleep. © 2013 Scientific American

Keyword: Sleep; Obesity
Link ID: 19061 - Posted: 12.21.2013

Don’t worry about watching all those cat videos on the Internet. You’re not wasting time when you are at your computer—you’re honing your fine-motor skills. A study of people’s ability to translate training that involves clicking and twiddling a computer mouse reveals that the brain can apply that expertise to other fine-motor tasks requiring the hands. We know that computers are altering the way that people think. For example, using the Internet changes the way that you remember information. But what about use of the computer itself? You probably got to this story by using a computer mouse, for example, and that is a bizarre task compared with the activities that we’ve encountered in our evolutionary history. You made tiny movements of your hand in a horizontal plane to cause tiny movements of a cursor in a completely disconnected vertical plane. But with daily practice—the average computer user makes more than 1000 mouse clicks per day—you have become such an expert that you don’t even think about this amazing feat of dexterity. Scientists would love to know if that practice affects other aspects of your brain’s control of your body. The problem is finding people with no computer experience. So Konrad Kording, a psychologist at Northwestern University’s Rehabilitation Institute of Chicago in Illinois, and his former postdoc Kunlin Wei, now at Peking University in Beijing, turned to migrant Chinese workers. The country’s vast population covers the whole socioeconomic spectrum, from elite computer hackers to agricultural laborers whose lifestyles have changed little over the past century. The country’s economic boom is bringing people in waves from the countryside to cities in search of employment. © 2013 American Association for the Advancement of Science

Keyword: Learning & Memory
Link ID: 19060 - Posted: 12.21.2013