Chapter 16. None

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James Gorman Deep in the mouse brain, scientists recently found that a very small network of cells, a few thousand at most, turns appetite on and off. They used the most sophisticated of modern techniques, but as has often happened in science — witness penicillin, Velcro and Viagra — the researchers discovered something they weren’t looking for. “This was an accidental discovery,” said David Anderson, of the California Institute of Technology, the senior scientist on the team that reported the finding, in Nature Neuroscience. The discovery may eventually lead to a better understanding and treatment of eating disorders. The surprise and drama of the finding are immediately clear, however, in lab videos. A mouse busily munches lab chow until a light signal is sent to its brain, and the mouse wanders off, no longer interested in food. His lab had previously studied this small group of neurons, in a part of the brain called the amygdala. That earlier research was on fear, an emotion strongly associated with the amygdala in both mice and humans. As a technique called optogenetics became more and more refined, he said, it seemed worth revisiting the neurons with this new tool. Optogenetics requires genetic manipulation of specific cells to make them sensitive to light in a certain wavelength, in this case blue light. Then fiber-optic cables are inserted into the brain, and when the light is turned on, neurons can be activated or turned off. Researchers in Dr. Anderson’s lab, including Haijiang Cai, a postdoctoral researcher and a co-author of the report, prepared the mice and conducted the experiment with the entirely unexpected result. © 2014 The New York Times Company

Keyword: Obesity
Link ID: 19945 - Posted: 08.12.2014

By Rachel Feltman Bioengineers have created the most realistic fake brain tissue ever – and it’s built like a jelly doughnut. The 3-D tissue, described in a paper published Monday in Proceedings of the National Academy of Sciences, is so structurally similar to a real rat brain (a common substitute for human brains in the lab) that it could help scientists answer longstanding questions about brain injuries and disease. Currently, the best way to study brain tissue is to grow neurons in a petri dish, but those neurons can only be grown flat. A real brain contains a complicated structure of 3-D tissue. Simply giving the neurons room to grow in three dimensions didn’t prove successful: While neurons will grow into more complicated structures in the right kind of gel, they don’t survive very long or mimic the structure of a real brain. Led by David Kaplan, the director of the Tissue Engineering Resource Center at Tufts University, researchers developed a new combination of materials to mimic the gray and white matter of the brain. The new model relies on a doughnut-shaped, spongy scaffold made of silk proteins with a collagen-based gel at the center. The outer scaffold layer, which is filled with rat neurons, acts as the grey matter of the brain. As the neurons grew networks throughout the scaffold, they sent branches out across the gel-filled center to connect with neurons on the other side. And that configuration is about as brain-like as lab-grown tissue can get. The basic structure can be reconfigured, too.

Keyword: Robotics; Aggression
Link ID: 19944 - Posted: 08.12.2014

By PAM BELLUCK The 40-year-old man showed up in Dr. Mary Malloy’s clinic with sadly disfiguring symptoms. His hands, elbows, ears and feet were blemished with protruding pustules and tuber-like welts, some so painful it was hard for him to walk. He suffered from a rare genetic condition called dysbetalipoproteinemia, which caused his cholesterol levels to soar so high that pools of fatty tissue seemed to bubble up under his skin. But there was something else about this patient. He was missing a gene that, when present in one form, greatly increases the risk of developing Alzheimer’s disease. Dr. Malloy, who co-directs the Adult Lipid Clinic at the University of California, San Francisco, and her colleagues saw an opportunity to answer an important neurological riddle: Does the absence of the gene — named apolipoprotein E, or APOE, after the protein it encodes — hurt the brain? If a person with this rare condition were found to be functioning normally, that would suggest support for a new direction in Alzheimer’s treatment. It would mean that efforts — already being explored by dementia experts — to prevent Alzheimer’s by reducing, eliminating or neutralizing the effects of the most dangerous version of APOE might succeed without causing other problems in the brain. The researchers, who reported their findings on Monday in the journal JAMA Neurology, discovered exactly that. They ran a battery of tests, including cognitive assessments, brain imaging and cerebrospinal fluid analyses. The man’s levels of beta-amyloid and tau proteins, which are markers of Alzheimer’s, gave no indication of neurological disease. His brain size was unaffected, and the white matter was healthy. His thinking and memory skills were generally normal. “This particular case tells us you can actually live without any APOE in the brain,” said Dr. Joachim Herz, a neuroscientist and molecular geneticist at University of Texas Southwestern Medical Center, who was not involved in the research. “So if they were to develop anti-APOE therapies for Alzheimer’s, we would not have to worry about serious neurological side effects.” © 2014 The New York Times Company

Keyword: Alzheimers
Link ID: 19943 - Posted: 08.12.2014

By ZACH SCHONBRUN EAST RUTHERFORD, N.J. — Victor Cruz dumped a bucket of ice water on his head at home on Sunday and then stepped out on thin ice himself — challenging the Giants’ co-owners to do the same. Taking part in the Ice Bucket Challenge — a social media craze that raises awareness for Lou Gehrig’s disease (amyotrophic lateral sclerosis) — Cruz, a wide receiver, posted the video on his Twitter feed. “That water was cold, man,” Cruz said Monday. The Ice Bucket Challenge was started by friends and family members of Pete Frates, a 29-year-old from Beverly, Mass., who played baseball at Boston College and was found to have A.L.S., a neurodegenerative condition, in 2012. As a reward for withstanding the icy punishment, the participant gets to nominate another person, who has 24 hours to complete the task. Cruz aimed high, calling out the co-owners John Mara and Steve Tisch to step under the bucket themselves. Just before practice on Monday, the 59-year-old Mara, wearing a white Giants T-shirt and black shorts, allowed Cruz to dump a Gatorade tub filled with ice water over his head. Before doing so, Mara nominated the Jets’ owner, Woody Johnson; the Patriots’ owner, Robert K. Kraft; and Patriots Coach Bill Belichick to do the same. “Feels good,” a smiling Mara said in a video posted on the Giants’ team website. It is unclear if Tisch will follow suit. Those who fail to complete the task within 24 hours are asked to donate to A.L.S. research. © 2014 The New York Times Company

Keyword: ALS-Lou Gehrig's Disease
Link ID: 19937 - Posted: 08.12.2014

|By William Skaggs One of the most frustrating and mysterious medical conditions affecting the mind is impaired consciousness, as can occur with brain damage. Patients in a coma or a vegetative or minimally conscious state sometimes spontaneously recover to varying degrees, but in most cases there is little that doctors can do to help. Now a rigorous study by a group at Liège University Hospital Center in Belgium has found that a simple treatment called transcranial direct-current stimulation (tDCS) can temporarily raise awareness in minimally conscious patients. In tDCS, electrodes are glued to the scalp, and a weak electric current is passed through them to stimulate the underlying brain tissue. Scientists led by neurologist Steven Laureys applied the electric current for 20 minutes to patients' left prefrontal cortex, an area known to be involved in attentiveness and working memory. Afterward, the effects on consciousness were measured by doctors who did not know whether the patient had received real tDCS or a sham treatment, in which the apparatus ran, but no current was delivered. For patients in a vegetative state, who display no communication or purposeful behavior, the stimulation might have led to improvement in two patients, but no statistically compelling evidence emerged. Yet 13 of 30 patients in a minimally conscious state—defined by occasional moments of low-level awareness—showed measurable gains in their responses to questions and sensory stimuli. Some had only recently been injured, but others had been minimally conscious for months. © 2014 Scientific American

Keyword: Consciousness
Link ID: 19934 - Posted: 08.11.2014

By SERGE F. KOVALESKI Nearly four years ago, Dr. Sue Sisley, a psychiatrist at the University of Arizona, sought federal approval to study marijuana’s effectiveness in treating military veterans with post-traumatic stress disorder. She had no idea how difficult it would be. The proposal, which has the support of veterans groups, was hung up at several regulatory stages, requiring the research’s private sponsor to resubmit multiple times. After the proposed study received final approval in March from federal health officials, the lone federal supplier of research marijuana said it did not have the strains the study needed and would have to grow more — potentially delaying the project until at least early next year. Then, in June, the university fired Dr. Sisley, later citing funding and reorganization issues. But Dr. Sisley is convinced the real reason was her outspoken support for marijuana research. “They could never get comfortable with the idea of this controversial, high-profile research happening on campus,” she said. Dr. Sisley’s case is an extreme example of the obstacles and frustrations scientists face in trying to study the medical uses of marijuana. Dating back to 1999, the Department of Health and Human Services has indicated it does not see much potential for developing marijuana in smoked form into an approved prescription drug. In guidelines issued that year for research on medical marijuana, the agency quoted from an accompanying report that stated, “If there is any future for marijuana as a medicine, it lies in its isolated components, the cannabinoids and their synthetic derivatives.” Scientists say this position has had a chilling effect on marijuana research. © 2014 The New York Times Company

Keyword: Drug Abuse
Link ID: 19933 - Posted: 08.11.2014

by Aviva Rutkin What can the human brain do for a computer? There's at least one team of researchers that thinks it might have the answer. Working at IBM Research–Almaden in San Jose, California, they have just released more details of TrueNorth, a computer chip composed of one million digital "neurons". Under way for several years, the project abandons traditional computer architecture for one inspired by biological synapses and axons. The latest results, published in Science, provide a timely reminder of the promise of brain-inspired computing. The human brain still crushes any modern machines when it comes to tasks like vision or voice recognition. What's more, it manages to do so with less energy than it takes to power a light bulb. Building those qualities into a computer is an alluring prospect to many researchers, like Kwabena Boahen of Stanford University in California. "The first time I learned how computers worked, I thought it was ridiculous," he says. "I basically felt there had to be a better way." Aping the brain's structure could help us build computers that are far more powerful and efficient than today's, says TrueNorth team leader Dharmendra Modha. "We want to approximate the anatomy and physiology, the structure and dynamics of the brain, within today's silicon technology," he says. "I think that the chip and the associated ecosystem have the potential to transform science, technology, business, government and society." But how best to go about building a proper artificial brain is a matter of debate. © Copyright Reed Business Information Ltd

Keyword: Robotics
Link ID: 19932 - Posted: 08.09.2014

Posted by Ewen Callaway More than 130 leading population geneticists have condemned a book arguing that genetic variation between human populations could underlie global economic, political and social differences. “A Troublesome Inheritance“, by science journalist Nicholas Wade, was published in June by Penguin Press in New York. The 278-page work garnered widespread criticism, much of it from scientists, for suggesting that genetic differences (rather than culture) explain, for instance, why Western governments are more stable than those in African countries. Wade is former staff reporter and editor at the New York Times, Science and Nature. But the letter — signed by a who’s who of population genetics and human evolution researchers, and to be published in the 10 August New York Times — represents a rare unified statement from scientists in the field and includes many whose work was cited by Wade. “It’s just a measure of how unified people are in their disdain for what was done with the field,” says Michael Eisen, a geneticist at the University of California, Berkeley, who co-drafted the letter. “Wade juxtaposes an incomplete and inaccurate explanation of our research on human genetic differences with speculation that recent natural selection has led to worldwide differences in I.Q. test results, political institutions and economic development. We reject Wade’s implication that our findings substantiate his guesswork. They do not,” states the letter, which is a response to a critical review of the book published in the New York Times. “This letter is driven by politics, not science,” Wade said in a statement. “I am confident that most of the signatories have not read my book and are responding to a slanted summary devised by the organizers.” © 2014 Macmillan Publishers Limited

Keyword: Genes & Behavior
Link ID: 19931 - Posted: 08.09.2014

Simon Makin Fish that have been exposed to a common anti-anxiety drug are more active and have better chances of survival than unexposed fish, researchers report in Environmental Research Letters1. The results suggest that standard methods for assessing the environmental impact of pharmaceuticals in waterways might miss some of the drugs' effects because they focus exclusively on harms, according to the authors. In the study, researchers led by Jonatan Klaminder at Umeå University in Sweden exposed Eurasian perch (Perca fluviatilis) to oxazepam, one of a widely used class of anti-anxiety drugs called benzodiazepines. Standard ecotoxicology experiments use unstressed, healthy fish that have been bred in labs. Control groups are designed to have 100% survival rates so that decreases in survival in the test group are easy to detect by comparison. But it is difficult to detect any increase in survival rates when the control group already has nearly complete survival. So Klaminder and his colleagues used the opposite approach. They exposed fish to the drug at two sensitive life stages: two-year-old wild fish taken from a Swedish lake that had only recently thawed after winter, and strings of roes — fish eggs that contain embryos undergoing development. These are more realistic conditions, the researchers say, as animals in the wild often experience high mortality. The researchers used oxazepam at a high concentration of 1,000 micrograms per litre and at a low concentration of 1 μg l−1. The low dose is relevant to aquatic environments in urban areas, because oxazepam concentrations of 1.9 μg l−1 have been measured in effluents from wastewater treatment plants. © 2014 Nature Publishing Group,

Keyword: Stress
Link ID: 19928 - Posted: 08.09.2014

By Emily Underwood The early signs of Creutzfeldt-Jakob disease (CJD)—a rare, incurable brain disorder caused by infectious, misshapen proteins called prions—are difficult to interpret. At first, people may simply feel depressed and can undergo personality changes or bouts of psychosis. By the time memory failure, blindness, and coma set in, typically within a year of infection, death is usually imminent. Now, researchers report that a simple nasal swab may help physicians detect the disease far more accurately and earlier than current methods. Finding simple, noninvasive diagnostic tests is “one of the holy grails” for CJD and other prion diseases, says biochemist Byron Caughey of the National Institute of Allergy and Infectious Diseases’ Rocky Mountain Laboratories in Hamilton, Montana, who helped lead the new work. Although there’s no cure for CJD, early diagnosis is important because it can help rule out other, treatable disorders, and it allows medical personnel to take precautions that prevent the disease from spreading to others through exposure to brain tissue or spinal fluid, he says. Researchers made a major stride toward better diagnostic methods in 2010, when Caughey and other researchers first described a new technique called the RT-QuIC test. The test requires removing cerebrospinal fluid (CSF) from patients by means of a spinal tap, putting samples into a bath of normally shaped prion proteins, and agitating the solution to encourage any abnormal prion “seeds” in the tissue to latch onto the regular proteins. If even trace amounts of pathogenic protein are present, they rapidly use the normal proteins to create millions of insoluble, fibrous amyloid strands. Researchers believe that these amyloid aggregates, also seen in other neurodegenerative diseases such as Alzheimer’s disease, ultimately cause CJD by interfering with or killing off neurons en masse. After death, the brains of people affected by CJD are so badly damaged that they often resemble Swiss cheese or sponges. © 2014 American Association for the Advancement of Science.

Keyword: Prions
Link ID: 19926 - Posted: 08.07.2014

Ian Sample, science correspondent The human brain can judge the apparent trustworthiness of a face from a glimpse so fleeting, the person has no idea they have seen it, scientists claim. Researchers in the US found that brain activity changed in response to how trustworthy a face appeared to be when the face in question had not been consciously perceived. Scientists made the surprise discovery during a series of experiments that were designed to shed light on the the neural processes that underpin the snap judgments people make about others. The findings suggest that parts of our brains are doing more complex subconscious processing of the outside world than many researchers thought. Jonathan Freeman at New York University said the results built on previous work that shows "we form spontaneous judgments of other people that can be largely outside awareness." The study focused on the activity of the amygdala, a small almond-shaped region deep inside the brain. The amygdala is intimately involved with processing strong emotions, such as fear. Its central nucleus sends out the signals responsible for the famous and evolutionarily crucial "fight-or-flight" response. Prior to the study, Freeman asked a group of volunteers to rate the trustworthiness of a series of faces. People tend to agree when they rank trustworthiness – faces with several key features, such as more furrowed brows and shallower cheekbones, are consistently rated as less trustworthy. Freeman then invited a different group of people to take part in the experiments. Each lay in an MRI scanner while images of faces flashed up on a screen before them. Each trustworthy or untrustworthy face flashed up for a matter of milliseconds. Though their eyes had glimpsed the images, the participants were not aware they had seen the faces. © 2014 Guardian News and Media Limited

Keyword: Attention
Link ID: 19924 - Posted: 08.07.2014

The gurgles made by a hungry belly are familiar to us all, but they are not just the side effect of an empty stomach. Brain cells not normally associated with communication send out a signal when they detect blood glucose levels are running low, and this triggers the stomach contractions. Richard Rogers of the Pennington Biomedical Research Center at Louisiana State University and colleagues used a drug called fluorocitrate to knock out the function of certain astrocytes and neurons in the brains of rats, blocking the sensation of hunger. Only when astrocyte function was restored did the gastric grumbles return, showing that it is these cells that respond to low glucose levels (Journal of Neuroscience, DOI: 10.1523/JNEUROSCI.1406-14.2014). The feeling of discomfort you get when hungry is called "hypoglycaemia awareness". "For most people this is only slightly unpleasant, but for diabetics whose glucose levels can drop significantly, [being hungry] can be dangerous," says Rogers. "It's important to understand how this mechanism works." © Copyright Reed Business Information Ltd.

Keyword: Obesity; Aggression
Link ID: 19922 - Posted: 08.07.2014

Sarah C. P. Williams Every fall, grizzly bears pack on the pounds in preparation for their winter hibernation. In humans, such extreme weight gain would likely lead to diabetes or other metabolic diseases, but the bears manage to stay healthy year after year. Their ability to remain diabetes-free, researchers have now discovered, can be chalked up to the shutting down of a protein found in fat cells. The discovery could lead to new diabetes drugs that turn off the same pathway in humans. The findings are “provocative and interesting,” says biologist Sandy Martin of the University of Colorado, Denver, who was not involved in the new work. “They found a natural solution to a problem that we haven’t been able to solve.” As people gain weight, fat, liver, and muscle cells typically become less sensitive to the hormone insulin—which normally helps control blood sugar levels—and insulin levels rise. In turn, that increased insulin prevents the breakdown of fat cells, causing a vicious cycle that can lead to full-blown insulin resistance, or diabetes. Developing new diabetes drugs has been hampered by the fact that findings from many mouse models of diabetes have not translated to humans. So Kevin Corbit, a senior scientist at Thousand Oaks, California–based drug company Amgen, decided to start looking at obesity and metabolic disease in other animals. “When I was thinking about things that are quite fat, one of the first things I thought of was bears, and what they do to prepare to go into hibernation,” he says. “But of course you don’t see bears running around with diabetes and heart disease.” © 2014 American Association for the Advancement of Science

Keyword: Obesity
Link ID: 19919 - Posted: 08.06.2014

Claudia M. Gold In the course of working on my new book about listening to parents and children, I have had the pleasure of immersing myself in the writing of D.W. Winnicott, pediatrician turned psychoanalyst. Winnicott's professional life included both caring for countless young children and families as a pediatrician, and psychoanalytic practice, where his adult patients "regressed to dependence," giving him an opportunity to interact with their infantile qualities, but with adult capacities for communication. This combination of experiences gave him a unique vantage point from which to make his many brilliant observations about children and the nature of the parent-child relationship. A recent New York Times Magazine article on autism prompted me to share his words of wisdom on the subject, which, though written in 1966, still have relevance today. The following is from a collection of papers, Thinking About Children: From my point of view the invention of the term autism was a mixed blessing...I would like to say that once this term has been invented and applied, the stage was set for something which is slightly false, i.e. the discovery of a disease…Pediatricians and physically minded doctors as a whole like to think in terms of diseases which gives a tidy look to the textbooks... The unfortunate thing is that in matters psychological things are not like that. Winnicott implores the reader to instead understand the child in relational and developmental context. He writes: The subject quickly becomes one not of autism and not of the early roots of a disorder that might develop in to autism, but rather one of the whole story of human emotional development and the relationship of the process in the individual child to the environmental provision which may or may not in any one particular case facilitate the maturational process. ©2014 Boston Globe Media Partners, LLC

Keyword: Autism
Link ID: 19915 - Posted: 08.05.2014

By Victoria Gill Science reporter, BBC News Very mobile ears help many animals direct their attention to the rustle of a possible predator. But a study in horses suggests they also pay close attention to the direction another's ears are pointing in order to work out what they are thinking. Researchers from the University of Sussex say these swivelling ears have become a useful communication tool. Their findings are published in the journal Current Biology. The research team studies animal behaviour to build up a picture of how communication and social skills evolved. "We're interested in how [they] communicate," said lead researcher Jennifer Wathan. "And being sensitive to what another individual is thinking is a fundamental skill from which other [more complex] skills develop." Ms Wathan and her colleague Prof Karen McComb set up a behavioural experiment where 72 individual horses had to use visual cues from another horse in order to choose where to feed. They led each horse to a point where it had to select one of two buckets. On a wall behind this decision-making spot was a life-sized photograph of a horse's head facing either to left or right. In some of the trials, the horses ears or eyes were covered. Horse images used in a study of horse communication The ears have it: Horses in the test followed the gaze of another horse, and the direction its ears pointed If the ears and eyes of the horse in the picture were visible, the horses being tested would choose the bucket towards which its gaze - and its ears - were directed. If the horse in the picture had either its eyes or its ears covered, the horse being tested would just choose a feed bucket at random. Like many mammals that are hunted by predators, horses can rotate their ears through almost 180 degrees - but Ms Wathan said that in our "human-centric" view of the world, we had overlooked the importance of these very mobile ears in animal communication. BBC © 2014

Keyword: Language; Aggression
Link ID: 19914 - Posted: 08.05.2014

By RUTH PADAWER At first, everything about L.'s baby boy seemed normal. He met every developmental milestone and delighted in every discovery. But at around 12 months, B. seemed to regress, and by age 2, he had fully retreated into his own world. He no longer made eye contact, no longer seemed to hear, no longer seemed to understand the random words he sometimes spoke. His easygoing manner gave way to tantrums and head-banging. “He had been this happy, happy little guy,” L. said. “All of a sudden, he was just fading away, falling apart. I can’t even describe my sadness. It was unbearable.” More than anything in the world, L. wanted her warm and exuberant boy back. A few months later, B. received a diagnosis of autism. His parents were devastated. Soon after, L. attended a conference in Newport, R.I., filled with autism clinicians, researchers and a few desperate parents. At lunch, L. (who asked me to use initials to protect her son’s privacy) sat across from a woman named Jackie, who recounted the disappearance of her own boy. She said the speech therapist had waved it off, blaming ear infections and predicting that Jackie’s son, Matthew, would be fine. She was wrong. Within months, Matthew acknowledged no one, not even his parents. The last word he had was “Mama,” and by the time Jackie met L., even that was gone. In the months and years that followed, the two women spent hours on the phone and at each other’s homes on the East Coast, sharing their fears and frustrations and swapping treatment ideas, comforted to be going through each step with someone who experienced the same terror and confusion. When I met with them in February, they told me about all the treatments they had tried in the 1990s: sensory integration, megadose vitamins, therapeutic horseback riding, a vile-tasting powder from a psychologist who claimed that supplements treated autism. None of it helped either boy. Together the women considered applied behavior analysis, or A.B.A. — a therapy, much debated at the time, that broke down every quotidian action into tiny, learnable steps, acquired through memorization and endless repetition; they rejected it, afraid it would turn their sons into robots. But just before B. turned 3, L. and her husband read a new book by a mother claiming that she used A.B.A. on her two children and that they “recovered” from autism. © 2014 The New York Times Company

Keyword: Autism
Link ID: 19913 - Posted: 08.02.2014

David Robson It’s not often that you look at your meal to find it staring back at you. But when Diane Duyser picked up her cheese toastie, she was in for a shock. “I went to take a bite out of it, and then I saw this lady looking back at me,” she told the Chicago Tribune. “It scared me at first.” As word got around, it soon began to spark more attention, and eventually a casino paid Duyser $28,000 to exhibit the toasted sandwich. For many, the woman’s soft, full features and serene expression recalls famous depictions of the Virgin Mary. But I’ve always thought the curled hair, parted lips and heavy eyelids evoke a more modern idol. Whichever Madonna you think you can see, she joins good company; Jesus has also been seen in toast, as well as a taco, a pancake and a banana peel, while Buzzfeed recently ran photos of peppers that look like British politicians. “If someone reports seeing Jesus in a piece of toast, you’d think they must be nuts,” says Kang Lee, at the University of Toronto, Canada. “But it’s very pervasive... We are primed to see faces in every corner of the visual world.” Lee has shown that rather than being a result of divine intervention, these experiences reflect the powerful influence of our imagination over our perception. Indeed, his explanation may mean that you never trust your eyes again. Pareidolia, as this experience is known, is by no means a recent phenomenon. Leonardo da Vinci described seeing characters in natural markings on stone walls, which he believed could help inspire his artworks. In the 1950s, the Bank of Canada had to withdraw a series of banknotes because a grinning devil leapt from the random curls of the Queen’s hair (although I can’t, for the life of me, see the merest hint of a horn in Her Majesty’s locks). The Viking I spacecraft, meanwhile, appeared to photograph a carved face in the rocky landscape of Mars. BBC © 2014

Keyword: Attention
Link ID: 19912 - Posted: 08.02.2014

By PHILIP M. BOFFEY For Michele Leonhart, the administrator of the Drug Enforcement Administration, there is no difference between the health effects of marijuana and those of any other illegal drug. “All illegal drugs are bad for people,” she told Congress in 2012, refusing to say whether crack, methamphetamines or prescription painkillers are more addictive or physically harmful than marijuana. Her testimony neatly illustrates the vast gap between antiquated federal law enforcement policies and the clear consensus of science that marijuana is far less harmful to human health than most other banned drugs and is less dangerous than the highly addictive but perfectly legal substances known as alcohol and tobacco. Marijuana cannot lead to a fatal overdose. There is little evidence that it causes cancer. Its addictive properties, while present, are low, and the myth that it leads users to more powerful drugs has long since been disproved. That doesn’t mean marijuana is harmless; in fact, the potency of current strains may shock those who haven’t tried it for decades, particularly when ingested as food. It can produce a serious dependency, and constant use would interfere with job and school performance. It needs to be kept out of the hands of minors. But, on balance, its downsides are not reasons to impose criminal penalties on its possession, particularly not in a society that permits nicotine use and celebrates drinking. Marijuana’s negative health effects are arguments for the same strong regulation that has been effective in curbing abuse of legal substances. Science and government have learned a great deal, for example, about how to keep alcohol out of the hands of minors. Mandatory underage drinking laws and effective marketing campaigns have reduced underage alcohol use to 24.8 percent in 2011, compared with 33.4 percent in 1991. Cigarette use among high school students is at its lowest point ever, largely thanks to tobacco taxes and growing municipal smoking limits. There is already some early evidence that regulation would also help combat teen marijuana use, which fell after Colorado began broadly regulating medical marijuana in 2010. © 2014 The New York Times Company

Keyword: Drug Abuse
Link ID: 19909 - Posted: 08.02.2014

By Emily Underwood Scientists don’t need superpowers to see through solid objects. For organs such as the brain, they have CLARITY, a technique for rendering tissue transparent by perfusing it with gel, then washing out the fatty molecules that make tissues opaque. Now, researchers have sped up the process, clearing whole rodent bodies within 2 weeks to create the transparent mice pictured above. Previously, it took that amount of time to clear a single mouse brain by soaking it in a bath of clearing chemicals. To accelerate the process, scientists delivered the gel and clearing agents directly into the bloodstreams of dead mice, clearing their kidneys, hearts, lungs, and intestines within days and their entire brains and bodies within weeks. Of what use is a see-through mouse corpse once completed? In a paper published online today in Cell, researchers say their new technique will allow them to map anatomical connections between the brain and body in unprecedented detail. © 2014 American Association for the Advancement of Science

Keyword: Brain imaging
Link ID: 19908 - Posted: 08.02.2014

Nishad Karim African penguins communicate feelings such as hunger, anger and loneliness through six distinctive vocal calls, according to scientists who have observed the birds' behaviour in captivity. The calls of the "jackass" penguin were identified by researchers at the University of Turin, Italy. Four are exclusive to adults and two are exclusive to juveniles and chicks. The study, led by Dr Livio Favaro, found that adult penguins produce distinctive short calls to express their isolation from groups or their mates, known as "contact" calls, or to show aggression during fights or confrontations, known as "agonistic" calls. They also observed an "ecstatic display song", sung by single birds during the mating season and the "mutual display song", a custom duet sung by nesting partners to each other. Juveniles and chicks produce calls relating to hunger. "There are two begging calls; the first one is where chicks utter 'begging peeps', short cheeps when they want food from adults, and the second one we've called 'begging moan', which is uttered by juveniles when they're out of the nest, but still need food from adults," said Favaro. The team made simultaneous video and audio recordings of 48 captive African penguins at the zoo Zoom Torino, over a 104 non-consecutive days. They then compared the audio recordings with the video footage of the birds' behaviour. Additional techniques, including visual inspection of spectrographs, produced statistical and quantifiable results. The research is published in the journal PLOS One. © 2014 Guardian News and Media Limited

Keyword: Language; Aggression
Link ID: 19905 - Posted: 07.31.2014