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By MATTHEW HUTSON ANGER is a primal and destructive emotion, disrupting rational discourse and inflaming illogical passions — or so it often seems. Then again, anger also has its upsides. Expressing anger, for example, is known to be a useful tool in negotiations. Indeed, in the past few years, researchers have been learning more about when and how to deploy anger productively. Consider a forthcoming paper in the November issue of the Journal of Experimental Social Psychology. Researchers tested the effectiveness of expressing anger in three types of negotiations: those that are chiefly cooperative (say, starting a business with a partner), chiefly competitive (dissolving a shared business) or balanced between the two (selling a business to a buyer). In two experiments, negotiators made greater concessions to those who expressed anger — but only in balanced situations. When cooperating, hostility seems inappropriate, and when competing, additional heat only flares tempers. But in between, anger appears to send a strategically useful signal. What does that signal communicate? According to a 2009 paper in Proceedings of the National Academy of Sciences, anger evolved to help us express that we feel undervalued. Showing anger signals to others that if we don’t get our due, we’ll exert harm or withhold benefits. As they anticipated, the researchers found that strong men and attractive women — those who have historically had the most leverage in threatening harm and conferring benefits, respectively — were most prone to anger. The usefulness of anger in extracting better treatment from others seems to be something we all implicitly understand. A 2013 paper in the journal Cognition and Emotion found that when people were preparing to enter a confrontational negotiation, as opposed to a cooperative one, they took steps to induce anger in themselves (choosing to listen to aggressive versus happy music, for example). © 2015 The New York Times Company

Keyword: Emotions
Link ID: 21426 - Posted: 09.21.2015

William Sutcliffe Most epidemics are the result of a contagious disease. ADHD – Attention Deficit Hyperactivity Disorder – is not contagious, and it may not even be a genuine malady, but it has acquired the characteristics of an epidemic. New data has revealed that UK prescriptions for Ritalin and other similar ADHD medications have more than doubled in the last decade, from 359,100 in 2004 to 922,200 last year. In America, the disorder is now the second most frequent long-term diagnosis made in children, narrowly trailing asthma. It generates pharmaceutical sales worth $9bn (£5.7bn) per year. Yet clinical proof of ADHD as a genuine illness has never been found. Sami Timimi, consultant child psychiatrist at Lincolnshire NHS Trust and visiting professor of child psychiatry, is a vocal critic of the Ritalin-friendly orthodoxy within the NHS. While he is at pains to stress that he is “not saying those who have the diagnosis don’t have any problem”, he is adamant that “there is no robust evidence to demonstrate that what we call ADHD correlates with any known biological or neurological abnormality”. The hyperactivity, inattentiveness and lack of impulse control that are at the heart of an ADHD diagnosis are, according to Timimi, simply “a collection of behaviours”. Any psychiatrist who claims that a behaviour is being caused by ADHD is perpetrating a “philosophical tautology” – he is doing nothing more than telling you that hyperactivity is caused by an alternative name for hyperactivity. There is still no diagnostic test – no marker in the body – that can identify a person with ADHD. The results of more than 40 brain scan studies are described by Timimi as “consistently inconsistent”. No conclusive pattern in brain activity had been found to explain or identify ADHD. ©

Keyword: ADHD
Link ID: 21425 - Posted: 09.21.2015

By Michael Balter Are some animals smarter than others? It’s hard to say, because you can’t sit a chimpanzee or a mouse down at a table for an IQ test. But a new study, in which scientists tested wild robins on a variety of skills, concludes that they do differ in the kind of “general intelligence” that IQ tests are supposed to measure. General intelligence is usually defined as the ability to do well on multiple cognitive tasks, from math skills to problem solving. For years, researchers have questioned whether measurable differences exist in humans and nonhumans alike. In humans, factors like education and socioeconomic status can affect performance. When it comes to animals, the problem is compounded for two main reasons: First, it is very difficult to design and administer tests that pick up on overall smarts instead of specific skills, such as the keen memories of food-hoarding birds or the fine motor skills of chimpanzees that make tools for finding insects in trees. Second, differences in animal test scores can depend on how motivated they are to perform. Because most experiments award would-be test-takers with food, an empty (or a full) stomach might be all it takes to skew the results. Thus, even studies that suggest variations in intelligence among mice, birds, and apes all carry the caveat that alternative explanations could be at play. To get around some of these limitations, a team led by Rachael Shaw, an animal behavior researcher at Victoria University of Wellington, turned to a population of New Zealand North Island robins for a new round of experiments. The robins live at the Zealandia wildlife sanctuary, a 225-hectare nature paradise in Wellington where more than 700 of the birds live wild and protected from predators in the middle of the city. © 2015 American Association for the Advancement of Science.

Keyword: Intelligence; Evolution
Link ID: 21424 - Posted: 09.20.2015

Mo Costandi The human brain is often said to be the most complex object in the known universe, and there’s good reason to believe that this old cliché is true. Even the apparently simple task of compiling a census of the different types of cells it contains has proven to be extremely difficult. Researchers still can’t agree on the best way to classify the numerous sub-types of neurons, and different methods produce different results, so estimates range from several hundred to over a thousand. Basket cells illustrate this neuronal identity crisis perfectly. They are currently sub-divided into multiple different types, according to their shape, electrical properties, and molecular profiles. After nearly ten years of detective work, researchers at King’s College London now reveal them to be masters of disguise. In a surprising new study, they show that these cells can dynamically switch from one identity to another in response to neuronal network activity. Basket cells are a type of interneuron, which are found scattered throughout the cerebral cortex, hippocampus, and cerebellum, and make up about 5% of the total number of cells in these brain regions. They form local circuits with each other and with pyramidal neurons, the much larger and more numerous cells that transmit information to distant parts of the brain, and synthesize the inhibitory neurotransmitter GABA, which dampens pyramidal cell activity when released. These enigmatic cells are thought to exist in more than twenty different types, the best known being the fast-spiking ones, which respond rapidly to incoming signals, and slower ones, which respond after a delay. During brain development, immature forms of all types of basket cells are created in a structure called the medial ganglionic eminence, along with various other types of brain cells. They then migrate into the developing cerebral cortex, before going on to form synaptic connections with other cells. © 2015 Guardian News and Media Limited

Keyword: Development of the Brain
Link ID: 21423 - Posted: 09.20.2015

By BENEDICT CAREY Fourteen years ago, a leading drug maker published a study showing that the antidepressant Paxil was safe and effective for teenagers. On Wednesday, a major medical journal posted a new analysis of the same data concluding that the opposite is true. That study — featured prominently by the journal BMJ — is a clear break from scientific custom and reflects a new era in scientific publishing, some experts said, opening the way for journals to post multiple interpretations of the same experiment. It comes at a time of self-examination across science — retractions are at an all-time high; recent cases of fraud have shaken fields as diverse as anesthesia and political science; and earlier this month researchers reported that less than half of a sample of psychology papers held up. “This paper is alarming, but its existence is a good thing,” said Brian Nosek, a professor of psychology at the University of Virginia, who was not involved in either the original study or the reanalysis. “It signals that the community is waking up, checking its work and doing what science is supposed to do — self-correct.” The authors of the reanalysis said that many clinical studies had some of the same issues as the original Paxil study, and that data should be made freely available across clinical medicine, so that multiple parties could analyze them. The dispute itself is a long-running one: Questions surrounding the 2001 study played a central role in the so-called antidepressant wars of the early 2000s, which led to strong warnings on the labels of Paxil and similar drugs citing the potential suicide risk for children, adolescents and young adults. The drugs are considered beneficial and less risky for many adults over 25 with depression. © 2015 The New York Times Company

Keyword: Depression; Development of the Brain
Link ID: 21422 - Posted: 09.20.2015

We all have our favourite movie moments, ones we love to watch again from time to time. Now it seems chimpanzees and bonobos, too, have the nous to recall thrilling scenes in movies they have previously seen and anticipate when they are about to come up. The results suggest apes can readily recall and anticipate significant recent events, just by watching those events once. Rather than use hidden food as a memory test, Japanese researchers made short movies and showed them to apes on two consecutive days. “We showed a movie instead, and asked whether they remember it when they only watch an event once, and an event totally new to them,” says Fumihiro Kano of Kyoto University in Japan. “Their anticipatory glances told us that they did.” Plot moment Kano and his colleague Satoshi Hirata made and starred in two short films. Another of the characters was a human dressed up as an ape in a King Kong costume who carried out attacks on people, providing the key plot moment in the first movie (see video). Both films were designed to contain memorable dramatic events, and the researchers deployed laser eye-tracking technology to see if the animals preferentially noticed and remembered these moments. © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory
Link ID: 21421 - Posted: 09.20.2015

Nathan Seppa For a historically mistrusted drink, coffee is proving to be a healthy addiction. Scientific findings in support of coffee’s nutritional attributes have been arriving at a steady drip since the 1980s, when Norwegian researchers reported that coffee seemed to fend off liver disease. Since then, the dark brown beverage has shown value against liver cancer, too, as well as type 2 diabetes, heart disease and stroke. Coffee even appears to protect against depression, Parkinson’s and Alzheimer’s diseases. Taken as a whole, these results might explain the most astonishing finding of all. People who drink two or more cups of coffee a day live longer than those who don’t, after accounting for behavioral differences, U.S. researchers reported in 2012. Studies in Japan, Scotland and Finland agree. Talk about a twofer. Coffee not only picks you up, it might put off the day they lower you down. Yet coffee has had trouble shaking its bad-for-you reputation. It may be one of the most widely consumed drinks in the world, but people have long assumed that, at least in its energizing caffeinated version, coffee comes with a catch. “People notice the caffeine,” says cardiologist Arthur Klatsky, who has researched coffee for decades at the Kaiser Permanente Northern California Division of Research in Oakland. “And there is this general feeling that anything that has some effect on the nervous system has to have something bad about it.” It doesn’t help that caffeine is mildly addictive.

Keyword: Drug Abuse; Parkinsons
Link ID: 21420 - Posted: 09.20.2015

By C. CLAIBORNE RAY A. Wild canines that rely on strenuous hunting to survive may sleep or rest as much as, or even more than, indolent human-created breeds that rely on a can or a bag of kibble. Domestic dogs, with their great range of body types and personalities, show a tremendous variety of sleep patterns, often including relatively brief periods of deep sleep spread out over several hours. A half-century-long study of wolves and their interaction with their prey on Isle Royale, a wilderness island in Lake Superior, found that in winter the wolves would feed for hours on a fresh kill, then sprawl out or curl up in the snow and rest or sleep about 30 percent of the time. “Wolves have plenty of reason to rest,” the study’s researchers wrote. “When wolves are active, they are really active. On a daily basis, wolves burn about 70 percent more calories compared to typical animals of similar size.” The researchers note that while hunting, wolves may burn calories at 10 to 20 times the rate they do while resting. “When food is plentiful, wolves spend a substantial amount of time simply resting, because they can,” the study said. “When food is scarce, wolves spend much time resting because they need to.” Wolves may eat only once every five to 10 days, the researchers said, losing as much as 8 to 10 percent of body weight, but regaining all the lost weight in just two days of eating and resting. © 2015 The New York Times Company

Keyword: Sleep
Link ID: 21419 - Posted: 09.20.2015

By David Grimm The journal Nature is revising its policy on publishing animal experiments after a study it ran in 2011 received criticism because the authors allowed tumors to grow excessively large in mice. The paper reported that a compound isolated from a pepper plant killed cancer cells without harming healthy cells. Yesterday, the journal published a correction to the study (the paper’s second), which noted that “some tumors on some of the animals exceeded the maximum size … permitted by the Institutional Animal Care and Use Committee.” The tumors were only supposed to grow to a maximum of 1.5 cubic centimeters, but some reached 7 cubic centimeters, according to David Vaux, a cell biologist at the Walter and Eliza Hall Institute of Medical Research in Melbourne, Australia, who first raised concerns about the paper in 2012. (Vaux spoke to Retraction Watch, which first reported the correction.) In an editorial published yesterday, Nature calls the large tumors “a breach of experimental protocol,” one that could have caused the mice to “have experienced more pain and suffering than originally allowed for.” The journal also noted the lapse could have implications beyond the one study, saying that “cases such as this could provoke a justifiable backlash against animal research.” Nature says it will now require authors to include the maximum tumor size allowed by its institutional animal-use committee, and to state that this size was not exceeded during the experiments. The journal does say, however, that it is not retracting the paper, and that the study remains “valid and useful.”

Keyword: Animal Rights
Link ID: 21418 - Posted: 09.20.2015

Helen Shen Neuroscientists have used ultrasound to stimulate individual brain cells in a worm, and hope that the technique — which they call ‘sonogenetics’ — might be adapted to switch on neurons in mice and larger animals. The technique relies on touch-sensitive ‘channel’ proteins, which can be added to particular brain cells through genetic engineering. The channels open when hit by an ultrasonic pulse, which allows ions to flood into a neuron and so causes it to turn on. Ultrasound could be a less-invasive way for researchers to stimulate specific cell types or individual neurons, rather than using implanted electrodes or fibre-optic cables, says neurobiologist Sreekanth Chalasani, at the Salk Institute for Biological Studies in La Jolla, California, who led the study reported today in Nature Communications1. “Our hope is to create a toolbox of different channels that would each respond to different intensities of ultrasound,” he says. "It's a cool new idea, and they show that this could really be feasible," says Jon Pierce-Shimomura, a neuroscientist who studies the nematode Caenorhabditis elegans at the University of Texas at Austin. “This could open a whole new way for manipulating the nervous system non-invasively through genetically encodable tools.” © 2015 Nature Publishing Group,

Keyword: Brain imaging
Link ID: 21417 - Posted: 09.16.2015

By JAMES GORMAN Among the deep and intriguing phenomena that attract intense scientific interest are the birth and death of the universe, the intricacies of the human brain and the way dogs look at humans. That gaze — interpreted as loving or slavish, inquisitive or dumb — can cause dog lovers to melt, cat lovers to snicker, and researchers in animal cognition to put sausage into containers and see what wolves and dogs will do to get at it. More than one experiment has made some things pretty clear. Dogs look at humans much more than wolves do. Wolves tend to put their nose to the Tupperware and keep at it. This evidence has led to the unsurprising conclusion that dogs are more socially connected to humans and wolves more self-reliant. Once you get beyond the basics, however, agreement is elusive. In order to assess the latest bit of research, published in Biology Letters Tuesday by Monique Udell at Oregon State University, some context can be drawn from an earlier experiment that got a lot of attention more than a decade ago. In a much publicized paper in 2003, Adam Miklosi, now director of the Family Dog Project, at Eotvos Lorand University in Budapest, described work in which dogs and wolves who were raised by humans learned to open a container to get food. Then they were presented with the same container, modified so that it could not be opened. Wolves persisted, trying to solve the unsolvable problem, while dogs looked back at nearby humans. At first glance it might seem to a dog lover that the dogs were brilliant, saying, in essence, “Can I get some help here? You closed it; you open it.” But Dr. Miklosi didn’t say that. He concluded that dogs have a genetic predisposition to look at humans, which could have been the basis for the intense but often imperfect communication that dogs and people engage in. © 2015 The New York Times Company

Keyword: Animal Communication; Language
Link ID: 21416 - Posted: 09.16.2015

By Sarah C. P. Williams Immune cells are usually described as soldiers fighting invading viruses and bacteria. But they may also be waging another battle: the war against fat. When mice lack a specific type of immune cell, researchers have discovered, they become obese and show signs of high blood pressure, high cholesterol, and diabetes. The findings have yet to be replicated in humans, but they are already helping scientists understand the triggers of metabolic syndrome, a cluster of conditions associated with obesity. The new study “definitely moves the field forward,” says immunologist Vishwa Deep Dixit of the Yale School of Medicine, who was not involved in the work. “The data seem really solid.” Scientists already know that there is a correlation between inflammation—a heightened immune response—and obesity. But because fat cells themselves can produce inflammatory molecules, distinguishing whether the inflammation causes weight gain or is just a side effect has been tricky. When he stumbled on this new cellular link between obesity and the immune system, immunologist Yair Reisner of the Weizmann Institute of Science in Rehovot, Israel, was studying something completely different: autoimmune diseases. An immune molecule called perforin had already been shown to kill diseased cells by boring a hole in their outer membrane. Reisner’s group suspected that dendritic cells containing perforin might also be destroying the body’s own cells in some autoimmune diseases. To test the idea, Reisner and his colleagues engineered mice to lack perforin-wielding dendritic cells, and then waited to see whether they developed any autoimmune conditions. © 2015 American Association for the Advancement of Science

Keyword: Obesity; Neuroimmunology
Link ID: 21415 - Posted: 09.16.2015

Nancy Shute There have been suggestions that low levels of vitamin D might be a factor in cognitive decline and Alzheimer's disease, but there's no proof that the lack of D is actually causing the problems. A study published Monday doesn't prove that link, but it does find that people with low levels of vitamin D lost key thinking skills more quickly than people with enough. The study is notable because of the diversity of the participants: 62 percent were women, 30 percent were African-American, 25 percent Hispanic and 41 percent white. Most earlier studies looking at cognitive decline and vitamin D were in white people. The participants lived in California's Sacramento Valley and were mostly in their 70s when they entered the study. The researchers followed up with them for about five years, having them take annual neurological exams and neuropsychological testing at the University of California, Davis, Alzheimer's Disease Center. Most of the 382 people in the study were low on vitamin D, tested by measuring 25-hydroxyvitamin D in the blood. One-quarter of the participants were deficient in vitamin D, and 35 percent had levels deemed insufficient. That's not a surprise — most older people are below the "adequate" level of 20 to less than 50 ng/ml, often because they're not outside much. And most of the people in the study weren't getting the recommended three servings of dairy foods daily that could help. © 2015 NPR

Keyword: Alzheimers; Hormones & Behavior
Link ID: 21414 - Posted: 09.16.2015

For primary school children in China, spending an extra 45 minutes per day outside in a school activity class may reduce the risk of nearsightedness, or "myopia," according to a new study. In some parts of China, 90 per cent of high school graduates have nearsightedness, and rates are lower but increasing in Europe and the Middle East, the authors write. "There were some studies suggesting the protective effect of outdoor time in the development of myopia, but most of this evidence is from cross-sectional studies [survey] data that suggest 'association' instead of causality," said lead author Dr. Mingguang He of Sun Yat-sen University in Guangzhou. "Our study, as a randomized trial, is able to prove causality and also provide the high level of evidence to inform public policy." Intense levels of schooling and little time spent outdoors may have contributed to the epidemic rise of nearsightedness in China, he told Reuters Health by email. The researchers divided 12 primary schools in China into two groups: six schools continued their existing class schedule, while six were assigned to include an additional 40 minutes of outdoor activity at the end of each school day. Parents of children in the second group were also encouraged to engage their children in outdoor activities on the weekends. In total, almost 2,000 first-graders, with an average age of almost seven years old, were included. After three years, 30 per cent of the outdoor activity group had developed nearsightedness, compared to almost 40 per cent of kids in the control group, according to the results in JAMA. ©2015 CBC/Radio-Canada.

Keyword: Vision
Link ID: 21413 - Posted: 09.16.2015

By Emily DeMarco When it comes to finding a mate in the animal kingdom, females tend to gravitate toward males who appear strong and healthy. But a new study in zebra finches reveals that the small, gray-striped birds prefer mates with similar interests, such as a penchant for exploring the world. The drive for this compatibility is so strong that when scientists forced the females to mate up with males not of their choosing, the birds were more likely to cheat and shirk their parental duties, leading to more deaths among their chicks. The research “suggests that having a mate you’re behaviorally compatible with is very important from an evolutionary perspective for zebra finches,” says behavioral ecologist Sasha Dall of the University of Exeter, Cornwall, in the United Kingdom, who wasn’t involved in the study. Scientists have long been puzzled by female zebra finches. As opposed to females of other bird species, which tend to prefer males with brighter plumage or longer tails (traits that suggest that the males have good, healthy genes), female zebra finches seem to choose mates for some mysterious reason known only to each lady bird. Sometimes one will go for the guy with the bright red beak, sometimes the male with the thrilling song, sometimes neither. So what’s really driving this mate choice? In the past, scientists have speculated that a desire for compatibility might be the answer. But they have disagreed over whether the birds are on the lookout for males with the right genes (genetic compatibility between the partners might help lower the high rates of embryonic mortality seen in the species) or the right behaviors. © 2015 American Association for the Advancement of Science

Keyword: Sexual Behavior
Link ID: 21412 - Posted: 09.15.2015

By Larry Greenemeier Advanced prosthetics have for the past few years begun tapping into brain signals to provide amputees with impressive new levels of control. Patients think, and a limb moves. But getting a robotic arm or hand to sense what it’s touching, and send that feeling back to the brain, has been a harder task. The U.S. Defense Department’s research division last week claimed a breakthrough in this area, issuing a press release touting a 28-year-old paralyzed person’s ability to “feel” physical sensations through a prosthetic hand. Researchers have directly connected the artificial appendage to his brain, giving him the ability to even identify which mechanical finger is being gently touched, according to the Defense Advanced Research Projects Agency (DARPA). In 2013, other scientists at Case Western Reserve University also gave touch to amputees, giving patients precise-enough feeling of pressure in their fingertips to allow them to twist the stems off cherries. The government isn’t providing much detail at this time about its achievement other than to say that researchers ran wires from arrays connected to the volunteer’s sensory and motor cortices—which identify tactile sensations and control body movements, respectively—to a mechanical hand developed by the Applied Physics Laboratory (APL) at Johns Hopkins University. The APL hand’s torque sensors can convert pressure applied to any of its fingers into electrical signals routed back to the volunteer’s brain. © 2015 Scientific American

Keyword: Pain & Touch; Robotics
Link ID: 21411 - Posted: 09.15.2015

A choir of Canadians with Parkinson's disease is helping researchers test how well the performers regain facial movement to express emotions. Tremors and difficulty walking are often the most noticeable symptoms of Parkinson's disease, which affects about one in 500 people in Canada. Those with the disease may also have limited facial movement, which hampers the ability to express themselves. For people with Parkinson's who have "masked face syndrome," it can be difficult for others to decipher how they're feeling. That's because we unknowingly mimic or mirror each other during interaction to connect. "Within a hundred milliseconds of seeing someone else smile or frown, we are smiling or frowning," said Frank Russo, a psychology professor at Ryerson University in Toronto. "We're mirroring what the other person is doing. And that's one of the things that is absent in Parkinson's. It's the absence of mirroring that is leading to some of the deficit in understanding other people's emotions." Having a static face can leave people with Parkinson's seem cold and aloof as they also show deficits in understanding other people's emotions. The patient can then become emotionally disconnected from others. Studying the 28 members of the Parkinson's choir has bolstered Russo's thinking that singing, facial expressions and social communications are interconnected. So far Russo has found that mirroring effect or mimicry was restored among choir participants who sang for 13 weeks. ©2015 CBC/Radio-Canada.

Keyword: Parkinsons; Emotions
Link ID: 21410 - Posted: 09.15.2015

By Barbara S. Moffet It’s 1 in the morning and I’ve been in bed for a few hours now. Maybe it’s the few drops of caffeine I mistakenly drank earlier in the day. Or perhaps it’s the 26 wires that are attached to my scalp, face, finger and legs and the strap pulled taut around my waist. All I know is I’m not doing what you’re supposed to do in a sleep lab, and if I don’t fall asleep soon, it’ll be time to take off my pajamas and go home. I’m here because my doctor thought it was time to find out what was causing a cluster of possibly sleep-related health issues: snoring, frequent middle-of-the-night waking and some problems with concentrating that I’ve had most of my 63 years. I also have a genetic condition, Ehler-Danlos syndrome, that can cause airways to partially close during sleep. I’ve landed at Sleep Centers of Northern Virginia in Alexandria, one of at least two dozen sleep labs in the area. According to the National Institutes of Health, some 70 million Americans are “poor sleepers,” and the ramifications of inadequate shut-eye can range from grumpiness and lack of focus to heart disease, diabetes, high blood pressure and even a diminished life expectancy. Research published this year in the journal Neurology concluded that people with sleep apnea — a disorder that causes a person to repeatedly stop breathing during the night, rousing them from sleep — developed problems with cognition about 10 years earlier than other people.

Keyword: Sleep
Link ID: 21409 - Posted: 09.15.2015

John Peever, and Brian J. Murray, The function of sleep has mystified scientists for thousands of years, but modern research is providing new clues about what it does for both the mind and body. Sleep serves to reenergize the body's cells, clear waste from the brain, and support learning and memory. It even plays vital roles in regulating mood, appetite and libido. Sleeping is an integral part of our life, and as research shows, it is incredibly complex. The brain generates two distinct types of sleep—slow-wave sleep (SWS), known as deep sleep, and rapid eye movement (REM), also called dreaming sleep. Most of the sleeping we do is of the SWS variety, characterized by large, slow brain waves, relaxed muscles and slow, deep breathing, which may help the brain and body to recuperate after a long day. When we fall asleep, the brain does not merely go offline, as implied by the common phrase “out like a light.” Instead a series of highly orchestrated events puts the brain to sleep in stages. Technically sleep starts in the brain areas that produce SWS. Scientists now have concrete evidence that two groups of cells—the ventrolateral preoptic nucleus in the hypothalamus and the parafacial zone in the brain stem—are involved in prompting SWS. When these cells switch on, it triggers a loss of consciousness. After SWS, REM sleep begins. This mode is bizarre: a dreamer's brain becomes highly active while the body's muscles are paralyzed, and breathing and heart rate become erratic. The purpose of REM sleep remains a biological mystery, despite our growing understanding of its biochemistry and neurobiology. © 2015 Scientific American

Keyword: Sleep
Link ID: 21408 - Posted: 09.15.2015

By AMY HARMON Some neuroscientists believe it may be possible, within a century or so, for our minds to continue to function after death — in a computer or some other kind of simulation. Others say it’s theoretically impossible, or impossibly far off in the future. A lot of pieces have to fall into place before we can even begin to start thinking about testing the idea. But new high-tech efforts to understand the brain are also generating methods that make those pieces seem, if not exactly imminent, then at least a bit more plausible. Here’s a look at how close, and far, we are to some requirements for this version of “mind uploading.” The hope of mind uploading rests on the premise that much of the key information about who we are is stored in the unique pattern of connections between our neurons, the cells that carry electrical and chemical signals through living brains. You wouldn't know it from the outside, but there are more of those connections — individually called synapses, collectively known as the connectome — in a cubic centimeter of the human brain than there are stars in the Milky Way galaxy. The basic blueprint is dictated by our genes, but everything we do and experience alters it, creating a physical record of all the things that make us US — our habits, tastes, memories, and so on. It is exceedingly tricky to transition that pattern of connections, known as the connectome, into a state where it is both safe from decay and can be verified as intact. But in recent months, two sets of scientists said they had devised separate ways to do that for the brains of smaller mammals. If either is scaled up to work for human brains — still a big if — then theoretically your brain could sit on a shelf or in a freezer for centuries while scientists work on the rest of these steps. © 2015 The New York Times Company

Keyword: Learning & Memory; Consciousness
Link ID: 21407 - Posted: 09.14.2015