Chapter 16. None

Follow us on Facebook and Twitter, or subscribe to our mailing list, to receive news updates. Learn more.


Links 41 - 60 of 2131

By Esther Hsieh Strap on a headset, immerse yourself in an alternate reality and cure your pain—that's the idea of a recent study in Psychological Science. Most people think of pain as something that happens in the body—I twist my head too far, and my neck sends a “pain signal” to the brain to indicate that the twisting hurts. In reality, pain is simply the brain telling us we are in danger. Although certain nerve endings throughout the body can indeed detect bodily harm, their signals are only one factor that the brain uses to determine if we should experience pain. Many cases of chronic pain are thought to be the result of obsolete brain associations between movement and pain. To explore the mind's influence over pain, Daniel Harvie, a Ph.D. candidate at the University of South Australia, and his colleagues asked 24 participants who suffer from chronic neck pain to sit in a chair while wearing virtual-reality glasses and turn their head. The displays were manipulated to make the participants think that they were turning their head more or less than they actually were. Subjects could swivel their head 6 percent more than usual if the virtual reality made them think they were turning less, and they could rotate 7 percent less than usual when they thought they were turning more. The findings suggest that virtual-reality therapy has the potential to retrain the brain to understand that once painful movements are now safe, extinguishing the association with danger. © 2015 Scientific American

Keyword: Pain & Touch
Link ID: 21155 - Posted: 07.11.2015

Simon Copland Over the past decade the idea that we are “born this way” — or that our sexuality is genetic — has become increasingly important. The mantra has become a political strategy, in particular for gay and lesbian communities, who see it as a way to protect themselves from discrimination. The movement has spawned blogs where people show pictures of their childhood to highlight the innate nature of their sexuality, and attacks on those who have questioned the theory. But do the politics match the science? People have been searching for biological explanations for sexual desires for centuries — primarily as a way to try and find a “cure” for “perverted desires”. In the most horrible of examples, the Nazi regime in Germany invested significant resources in attempts to find the reasons for homosexuality in attempt to cure it. In recent decades the search for a “gay gene” has intensified. In 1991, for example, Simon LeVay released a study that suggested small differences in the size of certain cells in the brain could influence sexual orientation in men. In 1993 this research turned to genetics, when Dean Hamer claimed that markers on the X chromosome could influence the development of same-sex orientation in men. The issue hit the headlines again last year after the release of a study from Dr. Alan Sanders. Sanders studied the genes on 409 pairs of gay brothers, finding they may share genetic markers on the X chromosome and chromosome 8. © 2015 Guardian News and Media Limited

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 21154 - Posted: 07.11.2015

By David Grimm The number of federally regulated animals used in U.S. biomedical research dropped last year to its lowest level since data collection began in 1972, according to new statistics posted by the U.S. Department of Agriculture (USDA). Approximately 834,000 rabbits, nonhuman primates, and other regulated animals were used in research last year, compared with more than 1.5 million in the early 1970s. The use of these animals has been on a downward trend since 1993, with a 6% decrease from 2013 to 2014. Since USDA first started posting its numbers on its website in 2008, total use has dropped 17%. The figures do not include most mice, rats, birds, and fish, which make up 98% of lab animals but are not covered under the 1966 Animal Welfare Act (AWA). “It’s a continuation of a long-running trend that’s showing no sign of slowing down—in fact it’s speeding up,” says Tom Holder, the director of Speaking of Research, a U.K.-based organization that supports the use of animals in research. Animal rights activists are “very pleased,” says Alka Chandna, the senior laboratory oversight specialist at People for the Ethical Treatment of Animals (PETA), which opposes the use of animals in research. The use of nearly every kind of AWA-covered animal dropped from 2013 to 2014. Twelve percent fewer dogs were used from 2013 to 2014 (16% fewer since 2008), 11% fewer rabbits (36% fewer since 2008), 11% fewer Guinea pigs (26% fewer since 2008), and 10% fewer nonhuman primates (19% fewer since 2008). The only animals to see an increase were “all other covered species,” which includes ferrets, squirrels, and some rodents (such as sand rats and deer mice) that are not excluded from the AWA. © 2015 American Association for the Advancement of Science

Keyword: Animal Rights
Link ID: 21153 - Posted: 07.11.2015

By Sarah Schwartz In a possible step toward treating genetic human deafness, scientists have used gene therapy to partially restore hearing in deaf mice. Some mice with genetic hearing loss could sense and respond to noises after receiving working copies of their faulty genes, researchers report July 8 in Science Translational Medicine. Because the mice’s mutated genes closely correspond to those responsible for some hereditary human deafness, the scientists hope the results will inform future human therapies. “I would call this a really exciting big step,” says otolaryngologist Lawrence Lustig of Columbia University Medical Center. The ear’s sound-sensing hair cells convert noises into information the brain can process. Hair cells need specific proteins to work properly, and alterations in the genetic blueprints for these proteins can cause deafness. To combat the effects of two such mutations, the scientists injected viruses containing healthy genes into the ears of deaf baby mice. The virus infected some hair cells, giving them working genes. The scientists tried this therapy on two different deafness-causing mutations. Within a month, around half the mice with one mutation showed brainwave activity consistent with hearing and jumped when exposed to loud noises. Treated mice with the other mutation didn’t respond to noises, but the gene therapy helped their hair cells — which normally die off quickly due to the mutation — survive. All of the untreated mice remained deaf. © Society for Science & the Public 2000 - 2015

Keyword: Hearing; Regeneration
Link ID: 21152 - Posted: 07.09.2015

By STEVE FEATHERSTONE One evening in April, Ethan Darbee, a 24-year-old paramedic in Syracuse, responded to a call on the city’s south side: unknown man down. Rolling up to the scene, he saw a figure lying motionless on the sidewalk. Darbee raked his knuckles across the man’s sternum to assess his level of consciousness. His eyelids fluttered. Inside the ambulance, Darbee hooked him up to a heart monitor, and he jerked involuntarily. The odd reaction puzzled Darbee. Why would the guy recoil from an electrode sticker but not a sternal rub? The driver started for the hospital. Darbee sat in the captain’s chair in the back of the rig, typing on a laptop. Then he heard a sound no paramedic ever wants to hear: the click of a patient’s shoulder harness unlatching. Swiveling around, he found himself eyeball to eyeball with his patient, who was now crouched on all fours on top of the stretcher, growling. That same evening, Heather Drake, a 29-year-old paramedic, responded to a call at an apartment complex on the west side. When she arrived, four firefighters were grappling with a 120-pound woman who was flailing and flinging vomit at anyone who came near her. A bystander shouted that the woman was high on ‘‘spike’’ — the prevailing local term for synthetic marijuana, which is more commonly known around the country as spice. But Drake didn’t believe it. Spike didn’t turn people into violent lunatics. Phencyclidine (PCP) or synthetic cathinones (‘‘bath salts’’) could do that, maybe even a joint soaked in formaldehyde — but not spike. Drake sprayed a sedative up the woman’s nose and loaded her into the ambulance. A mayday call from another crew came over the radio. In the background static of the transmission, Drake could hear Ethan Darbee yelling. Darbee’s patient had sprung off the stretcher and knocked him to the floor of the ambulance, punching him repeatedly in the face. Darbee grasped the side-door handle and tumbled into the street. Within moments, the police arrived and quickly subdued the man. Two days later, 19 more spike overdoses would swamp local emergency rooms, more in one day in Syracuse than the number of overdoses reported statewide in most states for all of April. © 2015 The New York Times Company

Keyword: Drug Abuse
Link ID: 21150 - Posted: 07.09.2015

By Christian Jarrett We all know a narcissist or two — the often-annoying colleagues, friends, and family members who seem to be constantly talking about themselves and touting their own achievements. In some ways, these characters are a paradox. They seem to be in love with themselves — and when they’re asked in questionnaires, they claim to have very high self-esteem — but their behavior poses an obvious question: If you were genuinely happy with yourself, why would you feel the need to constantly boast and seek admiration from others? A new study in Social Cognitive and Affective Neuroscience potentially solves the mystery: Narcissists may talk and act confident, but their brains don’t lie. At a neural level, narcissists are needy. A research team led by David Chester at the University of Kentucky at Lexington recruited 50 undergrad students and had them complete a standard measure of narcissism. Participants who agreed with statements like “I think I am a special person” were allocated high narcissism scores. Next, the researchers invited the students to lie in a special kind of brain scanner that uses diffusion tensor imaging, a technology that measures the amount of connectivity between different brain areas. Such scans produce beautiful “wiring diagrams” of the brain, in contrast to structural MRI scans that show the brain’s gray matter, and functional MRI scans that measure neural activity — this allows researchers to better understand how much “conversation” there is between the brain’s various functional hubs.

Keyword: Emotions
Link ID: 21148 - Posted: 07.09.2015

by Bob Holmes Bonobos can be just as handy as chimpanzees. In fact, bonobos' tool-using abilities look a lot like those of early humans, suggesting that observing them could teach anthropologists about how our own ancestors evolved such skills. Until now, bonobos have been more renowned for their free and easy sex lives than their abilities with tools. They have never been seen to forage using tools in the wild, although only a handful of wild populations have been studied because of political instability in the Democratic Republic of the Congo, where they live. As for those in captivity, Itai Roffman of Haifa University in Israel and his colleagues previously observed one captive bonobo, called Kanzi, using stone tools to crack a log and extract food. However, it was possible that Kanzi was a lone genius, raised by humans and taught sign language, as well as once being shown how to use tools. To find out if other captive bonobos shared Kanzi's aptitude, Roffman's team looked to animals at a zoo in Germany and a bonobo sanctuary in Iowa. The team gave them a series of problems that required tools to solve – for example, showing the bonobos that food was buried under rocks, then leaving a tray of potential aids such as sticks and antlers nearby. Two of eight zoo animals and four of seven in the sanctuary made use of the tools – in some cases almost immediately. The bonobos used sticks, rocks and antlers to dig, and also used long sticks as levers to move larger rocks out of the way (see video above). Some used different tools in sequence. © Copyright Reed Business Information Ltd

Keyword: Evolution
Link ID: 21147 - Posted: 07.08.2015

By Lenny Bernstein Primed by widespread use of prescription opioid pain-killers, heroin addiction and the rate of fatal overdoses have increased rapidly over the past decade, touching parts of society that previously were relatively unscathed, the Centers for Disease Control and Prevention reported Tuesday. The death rate from overdoses nearly quadrupled to 2.7 per 100,000 people between 2002 and 2013, CDC Director Tom Frieden said during a telephone news conference Tuesday. In 60 percent of those cases, the cause of death was attributed to heroin and at least one other drug, often cocaine, according to Chris Jones, lead author of the report and a member of the Food and Drug Administration's Office of Public Health Strategy and Analysis. But it is the highly addictive pain-killing opioids, prescribed and sometimes over-prescribed by physicians who are not highly trained in pain management, that concerns officials most, Frieden said. "A few doses and someone can have a life of addiction, a few too many and someone can die of an overdose," Frieden said. With heroin an estimated five times less expensive than prescription drugs and widely available on the street, people with opioid addictions are turning to the drug in large numbers, he said. The annual rate of heroin use rose from 1.6 per 1,000 people between 2002 and 2004 to 2.6 per 1,000 between 2011 and 2013, according to the report. That includes a doubling among women, a 114 percent increase for whites and a 109 percent rise among people ages 18 to 25, the report shows.

Keyword: Drug Abuse
Link ID: 21146 - Posted: 07.08.2015

By David Shultz Like many arthropods, spiders don’t have penises. Instead they rely on a set of modified appendages—termed pedipalps—to transfer sperm during reproduction. Previous studies had concluded that the pedipalps, which are basically modified arms emanating from the arachnid’s head, were lacking any sort of neurons that might convey a sense of touch. But new research, published online today in Biology Letters, suggests that the spider’s sex life isn’t an entirely numb deal. Using a combination of histological and computer-based techniques, scientists have identified neurons in the pedipalps of the Tasmanian cave spider (Hickmania troglodytes, seen above). Two main groups of nervous tissue were present: a nerve running to the tip of the sex organ, and two clusters of neurons in the palpal bulb—the region of the pedipalps used for transferring sperm. Though further research is needed to confirm the hypothesis, the team suspects that the sense of touch may enable the males to stimulate the females and even provide feedback about the quality of their mate. The latter hypothesis is especially intriguing because the analyses also revealed that one of the glands in the spider’s sex organ was directly innervated. The team believes this might mean the spiders can control the quality and volume of their ejaculate—reserving the best secretions for the choicest mates. © 2015 American Association for the Advancement of Science

Keyword: Sexual Behavior
Link ID: 21145 - Posted: 07.08.2015

By Michael T. Ullman and Mariel Y. Pullman The human brain possesses an incredible capacity to adapt to new conditions. This plasticity enables us not only to constantly learn but also to overcome brain injury and loss of function. Take away one capability, and little by little we often compensate for these deficits. Our brain may be especially well suited to overcome limitations in the case of psychiatric or neurological conditions that originate early in life, what clinicians call neurodevelopmental disorders. Given the brain's considerable plasticity during early years, children with these disorders may have particular advantages in learning compensatory strategies. It now appears that a single brain system—declarative memory—can pick up slack for many kinds of problems across multiple neurodevelopmental disorders. This system, rooted in the brain's hippocampus, is what we typically refer to when we think of learning and memory. It allows us to memorize facts and names or recall a first grade teacher or a shopping list. Whereas other memory systems are more specialized—helping us learn movements or recall emotional events, for instance—declarative memory absorbs and retains a much broader range of knowledge. In fact, it may allow us to learn just about anything. Given declarative memory's powerful role in learning, one might expect it to help individuals acquire all kinds of compensatory strategies—as long as it remains functional. Indeed, research suggests that it not only remains largely intact but also compensates for diverse impairments in five common conditions that are rarely studied in conjunction: autism spectrum disorder, obsessive-compulsive disorder (OCD), Tourette's syndrome, dyslexia and developmental language disorder (which is often referred to as specific language impairment, or SLI). © 2015 Scientific American

Keyword: Learning & Memory
Link ID: 21143 - Posted: 07.07.2015

By JAMES GORMAN Call it the case of the homing lizards. It’s a small mystery. No one of any species is murdered. But the central question is one that has prompted plenty of scientific research: How do animals find their way home? The lizards in this case are anoles — abundant, mostly small reptiles that thrive in the Caribbean. The species is Anolis gundlachi. The lead detective is Manuel Leal, a biologist at the University of Missouri. He has been studying the behavior of anoles for more than 20 years. For about three years, Dr. Leal has been trying to understand how the anole finds its way back to its own territory after being carried into the rain forest. And as he told an audience in June at the annual meeting of the Animal Behavior Society in Anchorage, the case is far from closed. First, a bit of background. Anoles are particularly abundant in the dense vegetation of the rain forests in Puerto Rico, where Dr. Leal studies them. Each species is tied to a very specific environment. For instance, many live on tree trunks, but only a particular part of the trunk. Trunk-ground anoles live only in the space from the ground up to six feet or so. Trunk-crown anoles live above them, up to the crown of the tree. Twig anoles live way up high. Several years ago, Dr. Leal was studying competition between two species. If he removed all of the trunk-ground anoles, he wondered, would the trunk-crown lizards extend their territory farther down the tree? He ran into a problem, however. He would take the trunk-ground lizards far from their home territory to make room for their upstairs neighbors, and then release them. But in a reptilian version of the children’s song, “The Cat Came Back,” the lizards wouldn’t stay away. “Lizards kept showing up in the territory that had just been scoured for lizards,” he said. Dr. Leal wondered whether new anoles were appearing in empty territory or the old ones were returning. But how could a lizard that had never left home find its way back through 25 yards or so of dense rain forest? © 2015 The New York Times Company

Keyword: Animal Migration
Link ID: 21141 - Posted: 07.07.2015

By Sabrina Imbler To our knowledge, there’s no correlation between a man’s singing ability and his care and attentiveness as a father. But any Pavarotti among the nightingales will serenade his mate while she sits on her eggs. And after they hatch he will visit the nest about 16 times each hour to feed their offspring. Because, among nightingales at least, the best singers also make the best fathers. So finds a study in the journal BMC Evolutionary Biology. [Conny Bartsch, Michael Weiss and Silke Kipper, Multiple song features are related to paternal effort in common nightingales] Some 80 percent of birds practice biparental care, meaning both the male and female rear their offspring together. So it’s crucial for a female bird to pick as a mate the most promising father—both genetically and behaviorally. Female birds look for signs of fitness that range from the flamboyant plumage of the peacock to the bizarre dances of birds of paradise. And for nightingales, it’s the most elaborate song that apparently wins the day. The average male has some 180 tunes in his repertoire. These avian Sinatras vocalize highly variable song types including buzzes, whistles and trills. And such virtuoso singing seems to signal the female that this is a guy she can count on. That is, when it’s time to help raise the kids, he’s not a flight risk. © 2015 Scientific American

Keyword: Sexual Behavior; Evolution
Link ID: 21140 - Posted: 07.07.2015

By DACHER KELTNER and PAUL EKMAN FIVE years ago, the writer and director Pete Docter of Pixar reached out to us to talk over an idea for a film, one that would portray how emotions work inside a person’s head and at the same time shape a person’s outer life with other people. He wanted to do this all in the mind of an 11-year-old girl as she navigated a few difficult days in her life. As scientists who have studied emotion for decades, we were delighted to be asked. We ended up serving as scientific consultants for the movie, “Inside Out,” which was recently released. Our conversations with Mr. Docter and his team were generally about the science related to questions at the heart of the film: How do emotions govern the stream of consciousness? How do emotions color our memories of the past? What is the emotional life of an 11-year-old girl like? (Studies find that the experience of positive emotions begins to drop precipitously in frequency and intensity at that age.) “Inside Out” is about how five emotions — personified as the characters Anger, Disgust, Fear, Sadness and Joy — grapple for control of the mind of an 11-year-old girl named Riley during the tumult of a move from Minnesota to San Francisco. (One of us suggested that the film include the full array of emotions now studied in science, but Mr. Docter rejected this idea for the simple reason that the story could handle only five or six characters.) Riley’s personality is principally defined by Joy, and this is fitting with what we know scientifically. Studies find that our identities are defined by specific emotions, which shape how we perceive the world, how we express ourselves and the responses we evoke in others. © 2015 The New York Times Company

Keyword: Emotions
Link ID: 21139 - Posted: 07.07.2015

By VIRGINIA HUGHES An extraterrestrial dropping into a modern-day hospital might be forgiven for thinking it was run by machines. Against a techno soundtrack of whirs and beeps, sleep-deprived doctors file in and out of exam rooms. They ask patients a series of standard questions, and make a few clicks on a computer to order a blood test or chest X-ray or pain meds. Then they hustle out the door to repeat the protocol on the impossibly large number of other patients under their watch. When their shifts end, some 12 or 18 or even 28 hours later, these zombies in blue scrubs are replaced by others, while the unflappable computers ease the handoff. The tech-centric approach to medicine has its benefits, to be sure. Imaging machines and genetic screening give doctors biological clues otherwise hidden. Computers can make hospitals more efficient, and prevent dumb mistakes. But the practice of medicine cannot be reduced to algorithms, pixels and protocols, as the neurologist Dr. Allan H. Ropper subtly argues in his entertaining book, “Reaching Down the Rabbit Hole.” (Read excerpt.) To Dr. Ropper, medicine is a craft — an art — that depends on the human interaction between doctor and patient. Like an episode of the popular television series “House,” the book presents mysterious medical cases from the behemoth Brigham and Women’s Hospital in Boston. The 10th floor holds the neurology inpatient ward, a place where, as Dr. Ropper and his co-author, Brian David Burrell, put it, “the strangest and most challenging cases are sent to be sorted out.” © 2015 The New York Times Company

Keyword: Miscellaneous
Link ID: 21138 - Posted: 07.07.2015

Gretchen Cuda Kroen When Kate Klein began working as a nurse in the Cleveland Clinic's Neurointensive Care Unit, one of the first things she noticed was that her patients spent a lot of time in bed. She knew patients with other injuries benefitted from getting up and moving early on, and she wondered why not patients with brain injuries. "I asked myself that question. I asked my colleagues that question," Klein says. "Why aren't these patients getting out of bed? Is there something unique about patients with neurologic injury?" Doctors have long encouraged their surgical patients to get out of bed as soon as it's safe to do so. Movement increases circulation, reduces swelling, inflammation and the risk of blood clots, and it speeds healing. But that wasn't the thinking with brain injuries, explains Edward Manno, director of the Neurointensive Care Unit at the Cleveland Clinic and one of the neurologists who works with Klein. "The predominant thinking was that rest was better suited for the brain," Manno says. Often the damaged brain is susceptible to lack of blood flow. Increased activity may make things worse if initiated too quickly, Manno says. "So many of us thought for quite some time that we needed to put the brain to rest after the initial insult of stroke or other neurologic injury." © 2015 NPR

Keyword: Brain Injury/Concussion
Link ID: 21136 - Posted: 07.06.2015

CONCORD, N.H. — Can an algorithm pass for an author? Can a robot rock the house? A series of contests at Dartmouth College is about to find out. Dartmouth is seeking artificial intelligence algorithms that create "human-quality" short stories, sonnets and dance music sets that will be pitted against human-produced literature, poetry and music selections. The judges won't know which is which. The goal is to determine whether people can distinguish between the two, and whether they might even prefer the computer-generated creativity. "Historically, often when we have advances in artificial intelligence, people will always say, 'Well, a computer couldn't paint a sunset,' or 'a computer couldn't write a beautiful love sonnet,' but could they? That's the question," said Dan Rockmore, director of the Neukom Institute for Computational Science at Dartmouth. Rockmore, a mathematics and computer science professor, spun off the idea for the contests from his experience riding a stationary bike. He started thinking about how the music being played during his spin class helped him pedal at the right the pace, and he was surprised when the instructor told him he selected the songs without the help of computer software. "I left there thinking, 'I wonder if I could write a program that did that, or somebody could?'" he said. "Because that is a creative act — a good spin instructor is a total artist. It sort of opened my mind to thinking about whether a computer or algorithm could produce something that was indistinguishable from or even perhaps preferred over what the human does." The competitions are variations of the "Turing Test," named for British computer scientist Alan Turing, who in 1950 proposed an experiment to determine if a computer could have humanlike intelligence. The classic Turing test involves intelligent computer programs that can fool a person carrying on a conversation with it, and there have been many competitions over the years, said Manuela Veloso, professor of computer science and robotics at Carnegie Mellon University and past president of the Association for the Advancement of Artificial Intelligence. © 2015 The New York Times Company

Keyword: Robotics
Link ID: 21135 - Posted: 07.06.2015

Taunya English What do we know about the power of food to rev up sex drive? Not much. "Really, science has not figured out what determines sexual motivation and sexual attraction. If we knew the answer to that, we'd probably be richer than Pfizer after they invented Viagra," says Dolores Lamb, director of the Center for Reproductive Medicine at Baylor College of Medicine. She hasn't seen any compelling evidence that any particular food can intensify desire. Lamb is a men's health researcher and knows a lot about the intricacies of male plumbing, but she says desire is largely psychological. Even medicines that treat erectile dysfunction can't create enthusiasm. "So the trigger still has to be up in the brain," Lamb says. Still, the idea persists that ginger stirs up lust, or that hot peppers make you hot. "Probably for some folks they do, and it's certainly fun to try," Lamb says. Some legendary aphrodisiacs do have a chemical here or a nutrient there that might support sexual health, but not enough of it to make an immediate difference in the bedroom. Red, juicy watermelon, for example, contains the amino acid citrulline, and that plant nutrient is healthy for erectile tissue in both men and women. But most of the amino acid is found in the rind of the fruit. Consider chili peppers. Capsaicin, which is what provides the heat in a jalapeno, also raises your metabolism and releases feel-good endorphins. "You get kind of a chill down the back of your neck and kind of a tingly, good sensation," Lamb says. "Gets blood flowing better." © 2015 NPR

Keyword: Sexual Behavior
Link ID: 21134 - Posted: 07.06.2015

By Adrian Cho Whether they're from humans, whales, or elephants, the brains of many mammals are covered with elaborate folds. Now, a new study shows that the degree of this folding follows a simple mathematical relationship—called a scaling law—that also explains the crumpling of paper. That observation suggests that the myriad forms of mammalian brains arise not from subtle developmental processes that vary from species to species, but rather from the same simple physical process. In biology, it rare to find a mathematical relationship that so tightly fits all the data, say Georg Striedter, a neuroscientist at the University of California, Irvine. "They've captured something," he says. Still, Striedter argues that the scaling law describes a pattern among fully developed brains and doesn't explain how the folding in a developing brain happens. The folding in the mammalian brain serves to increase the total area of the cortex, the outer layer of gray matter where the neurons reside. Not all mammals have folded cortices. For example, mice and rats have smooth-surfaced brains and are "lissencephalic." In contrast, primates, whales, dogs, and cats have folded brains and are "gyrencephalic." For decades, scientists have struggled to relate the amount of folding in a species' brain to some other characteristic. For example, although animals with tiny brains tend to have smooth ones, there is no clean relationship between the amount of folding—measured by the ratio of the total area of the cortex to the exposed outer surface of the brain—and brain mass. Make a plot of folding versus brain mass for various species and the data points fall all over and not on a unified curve. Similarly, there is no clean relationship between the amount of folding and the number of neurons, the total area of the cortex, or the thickness of the cortex. © 2015 American Association for the Advancement of Science

Keyword: Development of the Brain; Evolution
Link ID: 21133 - Posted: 07.04.2015

By BARRY MEIER and DANIELLE IVORY In a small brick building across the street from a Taco Bell in Marrero, La., patients enter a clear plastic capsule and breathe pure oxygen. The procedure, known as hyperbaric oxygen therapy, uses a pressurized chamber to help scuba divers overcome the bends and to aid people sickened by toxic gases. But Dr. Paul G. Harch, who operates the clinic there on the outskirts of New Orleans, offers it as a concussion treatment. One patient, Rashada Parks, said that she had struggled with neck pain, mood swings and concentration problems ever since she fell and hit her head more than three years ago. Narcotic painkillers hadn’t helped her, nor had antidepressants. But after 40 hourlong treatments, or dives, in a hyperbaric chamber, her symptoms have subsided. “I have hope now,” Ms. Parks said. “It’s amazing.” Three studies run at a taxpayer cost of about $70 million have all come to a far different conclusion. They found that the benefits of hyperbaric oxygen reported by patients like Ms. Parks may have resulted from a placebolike effect, not the therapy’s supposed ability to repair and regenerate brain cells. But undeterred, advocates of the treatment recently persuaded lawmakers to spend even more public money investigating whether the three studies were flawed. A growing industry has developed around concussions, with entrepreneurs, academic institutions and doctors scrambling to find ways to detect, prevent and treat head injuries. An estimated 1.7 million Americans are treated every year after suffering concussions from falls, car accidents, sports injuries and other causes. While the vast majority quickly recover with rest, a small percentage of patients experience lingering effects a year or longer afterward. Along with memory issues, symptoms can include headaches, dizziness and vision and balance problems. © 2015 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 21132 - Posted: 07.04.2015

By Kelly Servick How many times would you give your neighbor an electric shock to earn a few extra bucks? Your answer could be more malleable than you think. A new study finds that two common drugs—an antidepressant and a treatment for Parkinson’s disease—can influence moral decisions, a discovery that could help unravel specific mechanisms behind aggression and eventually help researchers design treatments for antisocial behavior. Previous research has linked two neurotransmitters, the brain’s signaling molecules, to our willingness to inflict harm. Serotonin appears to help keep us civil; it’s reduced in the brains of violent offenders, for example. Dopamine, meanwhile, has been shown to prompt aggression in animals, and it’s elevated in a certain part of the brain in people with psychopathic behavior. But measuring how these neurotransmitters contribute to moral decision-making is hard to do in the lab. Many studies rely on theoretical questions like the so-called trolley dilemma, which asks a person whether they would redirect an oncoming train to kill someone if it would save the lives of several others in its path. A person’s answer might not always reflect how they would behave in real life, however. So neuroscientist Molly Crockett of the University of Oxford in the United Kingdom and her colleagues developed a lab test with real consequences. They asked subjects to make a series of decisions about how many moderately painful electric shocks to deliver to themselves or to others. Half the questions gave volunteers a chance to earn money by inflicting self-harm. (For example: “Would you rather endure seven shocks to earn $10 or 10 shocks to earn $15?”) The other half offered the same type of decision, except that someone else stood to be shocked. At the end of the experiment, one of these choices was randomly selected and carried out: The decision-maker got paid, and either they or another person—waiting in a different room—got a series of painful zings on the wrist. Any answer could be the one with real consequences, so “people have to sort of put their money where their mouth is,” Crockett says. © 2015 American Association for the Advancement of Science

Keyword: Emotions
Link ID: 21131 - Posted: 07.04.2015