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by Clare Wilson Could a lopsided gap help set us apart from our primate cousins? Our brains and chimps' are built differently in the areas that give us our social skills and language. The human brain has a 4.5-centimetre-long groove running deeper along the right side than the left. Chimp brains lack this asymmetry, as François Leroy of the French National Institute of Health and Medical Research in Saclay, and colleagues, have discovered. The groove's function is unknown, but its location suggests it played a role in the evolution of our communication abilities. "One day this will help us understand what makes us tick," says Colin Renfrew of the University of Cambridge, who was not involved in the study. Although our brain is about three times the size of a chimp's, anatomical features that only the human brain possesses are surprisingly hard to find. One known difference is in a region called Broca's area, which is also involved in speech and is larger in humans than chimps. The asymmetrical groove in humans was also known, but the new study, in which 177 people and 73 chimps had brain scans, revealed it is almost completely absent in the other primates. In humans, the deeper groove in the right brain lies in the region that controls voice and face recognition and working out what other people are thinking – our so-called theory of mind. The shallower groove on the left is at the heart of the areas associated with language. The lack of symmetry could signify that tissue layers in the right brain have been reorganised, says Leroy. © Copyright Reed Business Information Ltd.
By Richard Leiby NEWPORT BEACH, Calif. — The headquarters of Oakley, a maker of recreational and military gear, looks as if it belongs in a war zone. It’s a massive bunker with exposed steel pipes, girders and blast walls. Even the dais in the auditorium is armored. But on a recent afternoon, the talk inside the building, set atop an arid, inland hillside in Orange County, is not about fighting wars but about caring for warriors. Doctors, scientists and veterans approach the podium at a conference to present some of the latest tools to help vets recover from wounds both mental and physical: bionics, virtual reality, magnetic waves. A session called “Healing the Warrior Brain” features a trim, bleach-blond former Army staff sergeant named Jonathan Warren, who recounts on video his struggle with post-traumatic stress disorder after combat in Iraq. His flashbacks, panic attacks and booze benders were well chronicled: For a year, the Los Angeles Times tracked Warren’s efforts to find peace, including via Department of Veterans Affairs therapy. It didn’t work, he says. But now a different Jon Warren is here to say that he is finally free of symptoms, one year after that 2013 story ran. No longer does his worst memory of the Iraq war — failing to rescue his best friend, who nearly burned to death after their Humvee hit a roadside bomb in 2006 — grasp his psyche and inflict guilt. That’s because of a revolutionary new treatment that retuned his brain, he says, and set “my frequencies right.” Now he’s able to proudly embrace his military service, “to keep the memory, to be able to go there,” Warren tells the audience, “and not be controlled by it.”
Link ID: 20474 - Posted: 01.13.2015
By KIRA PEIKOFF At a recent Seahawks football game in Seattle, Shy Sadis, 41, took a drag on a slim vapor pen that looked like a jet black Marlboro. The tip glowed red as he inhaled. But the pen contained no nicotine. Instead, it held 250 milligrams of cannabis oil loaded with THC, the psychoactive ingredient in marijuana. “Nobody noticed,” said Mr. Sadis, who owns several marijuana dispensaries in Washington State. “You pull it out of your pocket, take a hit like a cigarette, put it back, and you’re done. It’s so discreet.” The device, called a JuJu Joint, heralds a union that seems all but inevitable: marijuana and the e-cigarette, together at last in an e-joint. For years, people have been stuffing marijuana in various forms into portable vaporizers and into the cartridges of e-cigarettes. But the JuJu Joint is disposable, requires no charging of batteries or loading of cartridges, and comes filled with 150 hits. You take it out of the package and put it to your lips — that’s it. There is no smoke and no smell. Since their introduction in April, 75,000 JuJu Joints have been sold in Washington State, where marijuana is recreationally and medically legal. The maker says that 500,000 will be sold this year and that there are plans to expand to Colorado and Oregon, where recreational use is legal, and to Nevada, where it is decriminalized. “I wanted to eliminate every hassle that has to do with smoking marijuana,” said Rick Stevens, 62, the inventor and co-founder of JuJu Joints with Marcus Charles, a Seattle entrepreneur. “I wanted it to be discreet and easy for people to handle. There’s no odor, matches or mess.” © 2015 The New York Times Company
Keyword: Drug Abuse
Link ID: 20473 - Posted: 01.13.2015
By James Gallagher Health editor, BBC News website The key to learning and memory in early life is a lengthy nap, say scientists. Trials with 216 babies up to 12 months old indicated they were unable to remember new tasks if they did not have a lengthy sleep soon afterwards. The University of Sheffield team suggested the best time to learn may be just before sleep and emphasised the importance of reading at bedtime. Experts said sleep may be much more important in early years than at other ages. People spend more of their time asleep as babies than at any other point in their lives. Yet the researchers, in Sheffield and Ruhr University Bochum, in Germany, say "strikingly little is known" about the role of sleep in the first year of life. Learn, sleep, repeat They taught six- to 12-month-olds three new tasks involving playing with hand puppets. Half the babies slept within four hours of learning, while the rest either had no sleep or napped for fewer than 30 minutes. The next day, the babies were encouraged to repeat what they had been taught. The results, published in Proceedings of the National Academy of Sciences, showed "sleeping like a baby" was vital for learning. On average one-and-a-half tasks could be repeated after having a substantial nap. Yet zero tasks could be repeated if there was little sleep time. Dr Jane Herbert, from the department of psychology at the University of Sheffield, told the BBC News website: "Those who sleep after learning learn well, those not sleeping don't learn at all." © 2015 BBC
By DOUGLAS QUENQUA A sparrow’s song may sound simple, consisting of little more than whistles and trills. But to the sparrows, those few noises can take on vastly different meanings depending on small variations in context and repetition, researchers have found. In humans, the ability to extract nearly endless meanings from a finite number of sounds, known as partial phonemic overlapping, was key to the development of language. To see whether sparrows shared this ability, researchers at Duke University recorded and analyzed the songs of more than 200 Pennsylvania swamp sparrows. They found that the sparrows’ whistles could be divided into three lengths: short, intermediate and long. The researchers then played the sparrows two versions of the songs — the original and a slightly altered one. They found that replacing a single short whistle with an intermediate one, for example, could significantly alter a bird’s reaction, but only if it came at the right moment in the song. “Identical sounds seemed to belong to a different category depending on the context,” said Robert F. Lachlan, a biologist now with Queen Mary University of London and the lead author of the study. The findings, which were published in Proceedings of the National Academy of Sciences, are part of a larger effort to better understand how human language evolved. If even birds rely on phonemic overlapping to communicate, Dr. Lachlan said, it could indicate that such features “developed independently of higher aspects of language.” © 2015 The New York Times Company
By GARETH COOK In 2005, Sebastian Seung suffered the academic equivalent of an existential crisis. More than a decade earlier, with a Ph.D. in theoretical physics from Harvard, Seung made a dramatic career switch into neuroscience, a gamble that seemed to be paying off. He had earned tenure from the Massachusetts Institute of Technology a year faster than the norm and was immediately named a full professor, an unusual move that reflected the sense that Seung was something of a superstar. His lab was underwritten with generous funding by the elite Howard Hughes Medical Institute. He was a popular teacher who traveled the world — Zurich; Seoul, South Korea; Palo Alto, Calif. — delivering lectures on his mathematical theories of how neurons might be wired together to form the engines of thought. And yet Seung, a man so naturally exuberant that he was known for staging ad hoc dance performances with Harvard Square’s street musicians, was growing increasingly depressed. He and his colleagues spent their days arguing over how the brain might function, but science offered no way to scan it for the answers. “It seemed like decades could go by,” Seung told me recently, “and you would never know one way or another whether any of the theories were correct.” That November, Seung sought the advice of David Tank, a mentor he met at Bell Laboratories who was attending the annual meeting of the Society for Neuroscience, in Washington. Over lunch in the dowdy dining room of a nearby hotel, Tank advised a radical cure. A former colleague in Heidelberg, Germany, had just built a device that imaged brain tissue with enough resolution to make out the connections between individual neurons. But drawing even a tiny wiring diagram required herculean efforts, as people traced the course of neurons through thousands of blurry black-and-white images. What the field needed, Tank said, was a computer program that could trace them automatically — a way to map the brain’s connections by the millions, opening a new area of scientific discovery. For Seung to tackle the problem, though, it would mean abandoning the work that had propelled him to the top of his discipline in favor of a highly speculative engineering project. © 2015 The New York Times Company
Keyword: Brain imaging
Link ID: 20470 - Posted: 01.10.2015
by Michael Hotchkiss Forget about it. Your brain is a memory powerhouse, constantly recording experiences in long-term memory. Those memories help you find your way through the world: Who works the counter each morning at your favorite coffee shop? How do you turn on the headlights of your car? What color is your best friend's house? But then your barista leaves for law school, you finally buy a new car and your buddy spends the summer with a paint brush in hand. Suddenly, your memories are out of date. What happens next? An experiment conducted by researchers from Princeton University and the University of Texas-Austin shows that the human brain uses memories to make predictions about what it expects to find in familiar contexts. When those subconscious predictions are shown to be wrong, the related memories are weakened and are more likely to be forgotten. And the greater the error, the more likely you are to forget the memory. "This has the benefit ultimately of reducing or eliminating noisy or inaccurate memories and prioritizing those things that are more reliable and that are more accurate in terms of the current state of the world," said Nicholas Turk-Browne, an associate professor of psychology at Princeton and one of the researchers. The research was featured in an article, "Pruning of memories by context-based prediction error," that appeared in 2014 in the Proceedings of the National Academy of Sciences. The other co-authors are Ghootae Kim, a Princeton graduate student; Jarrod Lewis-Peacock, an assistant professor of psychology at the University of Texas-Austin; and Kenneth Norman, a Princeton professor of psychology and the Princeton Neuroscience Institute. © Medical Xpress 2011-2014,
Keyword: Learning & Memory
Link ID: 20469 - Posted: 01.10.2015
By Richard A. Friedman, M.D. You’re feeling down, and your doctor or therapist has confirmed it: You have depression. Now what? Until recently, many experts thought that your clinician could literally pick any antidepressant or type of psychotherapy at random because, with a few clinical exceptions, there was little evidence to favor one treatment over another for a given patient. In fact, I used to delight in tormenting the drug company representatives when they asked me how I picked an antidepressant. I would take a quarter out of my pocket, flip the coin and say I’d let chance decide because their drug was no better or worse than their competitors’. Although the holy grail of personalized therapy — be it with psychotropic drugs or psychotherapy — has proved elusive, we’ve learned a lot recently about individual factors that might predict a better response to one type of treatment over another. Dr. Helen Mayberg, a professor of psychiatry at Emory University, recently published a study in JAMA Psychiatry that identified a potential biomarker in the brain that could predict whether a depressed patient would respond better to psychotherapy or antidepressant medication. Using PET scans, she randomized a group of depressed patients to either 12 weeks of treatment with the S.S.R.I. antidepressant Lexapro or to cognitive behavior therapy, which teaches patients to correct their negative and distorted thinking. Over all, about 40 percent of the depressed subjects responded to either treatment. But Dr. Mayberg found striking brain differences between patients who did well with Lexapro compared with cognitive behavior therapy, and vice versa. Patients who had low activity in a brain region called the anterior insula measured before treatment responded quite well to C.B.T. but poorly to Lexapro; conversely, those with high activity in this region had an excellent response to Lexapro, but did poorly with C.B.T. © 2015 The New York Times Company
Link ID: 20468 - Posted: 01.10.2015
Ewen Callaway The ability to recognize oneself in a mirror has been touted as a hallmark of higher cognition — present in humans and only the most intelligent of animals — and the basis for empathy. A study published this week in Current Biology controversially reports that macaques can be trained to pay attention to themselves in a mirror, the first such observation in any monkey species1. Yet the finding raises as many questions as it answers — not only about the cognitive capacity of monkeys, but also about mirror self-recognition as a measure of animal intelligence. “Simply because you’re acting as if you recognize yourself in a mirror doesn’t necessarily mean you’ve achieved self-recognition,” says Gordon Gallup, an evolutionary psychologist at the State University of New York in Albany, who in 1970 was the first to demonstrate mirror self-recognition in captive chimpanzees2. When most animals encounter their reflections in a mirror, they act as if they have seen another creature. They lash out aggressively, belt out loud calls and display other social behaviours. This is how chimps first acted when Gallup placed a full-length mirror next to their cages. But after a couple of days, their attitudes changed and they started examining themselves, says Gallup. “They’d look at the inside of their mouths; they’d watch their tongue move.” This convinced him that the chimps recognized themselves in the mirror. He knew other scientists would be sceptical, so he developed a test of mirror self-recognition. After chimps started acting as if they saw themselves in the mirror, after about 10 days, he anaesthetized them and applied an odour-free red mark to a location on their faces they could not see, such as above the brow ridge. © 2015 Nature Publishing Group
Link ID: 20467 - Posted: 01.10.2015
By ANDREW POLLACK Driving to a meeting in 2008, Jay Lichter, a venture capitalist, suddenly became so dizzy he had to pull over and call a friend to take him to the emergency room. The diagnosis: Ménière’s disease, a disorder of the inner ear characterized by debilitating vertigo, hearing loss and tinnitus, or ringing in the ears. But from adversity can spring opportunity. When Mr. Lichter learned there were no drugs approved to treat Ménière’s, tinnitus or hearing loss, he started a company, Otonomy. It is one of a growing cadre of start-ups pursuing drugs for the ear, an organ once largely neglected by the pharmaceutical industry. Two such companies, Otonomy and Auris Medical, went public in 2014. Big pharmaceutical companies like Pfizer and Roche are also exploring the new frontier. A clinical trial recently began of a gene therapy being developed by Novartis that is aimed at restoring lost hearing. The sudden flurry of activity has not yet produced a drug that improves hearing or silences ringing in the ears, but some companies are reporting hints of promise in early clinical trials. There is a huge need, some experts say. About 48 million Americans have a meaningful hearing loss in at least one ear; 30 million of them have it in both ears, said Dr. Frank R. Lin, an associate professor of otolaryngology and geriatric medicine at Johns Hopkins University. That figure is expected to increase as baby boomers grow older. © 2015 The New York Times Company
Link ID: 20466 - Posted: 01.10.2015
By James Gallagher Health editor, BBC News website An elastic implant that moves with the spinal cord can restore the ability to walk in paralysed rats, say scientists. Implants are an exciting field of research in spinal cord injury, but rigid designs damage surrounding tissue and ultimately fail. A team at Ecole Polytechnique Federale de Lausanne (EPFL) has developed flexible implants that work for months. It was described by experts as a "groundbreaking achievement of technology". The spinal cord is like a motorway with electrical signals rushing up and down it instead of cars. Injury to the spinal cord leads to paralysis when the electrical signals are stuck in a jam and can no longer get from the brain to the legs. The same group of researchers showed that chemically and electrically stimulating the spinal cord after injury meant rats could "sprint over ground, climb stairs and even pass obstacles". Rat walks up stairs Previous work by the same researchers But that required wired electrodes going directly to the spinal cord and was not a long-term option. Implants are the next step, but if they are inflexible they will rub, causing inflammation, and will not work properly. The latest innovation, described in the journal Science, is an implant that moves with the body and provides both chemical and electrical stimulation. When it was tested on paralysed rats, they moved again. One of the scientists, Prof Stephanie Lacour, told the BBC: "The implant is soft but also fully elastic to accommodate the movement of the nervous system. "The brain pulsates with blood so it moves a lot, the spinal cord expands and retracts many times a day, think about bending over to tie your shoelaces. "In terms of using the implant in people, it's not going to be tomorrow, we've developed dedicated materials which need approval, which will take time. © 2015 BBC.
Link ID: 20465 - Posted: 01.10.2015
Ewen Callaway Microscopes make living cells and tissues appear bigger. But what if we could actually make the things bigger? It might sound like the fantasy of a scientist who has read Alice’s Adventures in Wonderland too many times, but the concept is the basis for a new method that could enable biologists to image an entire brain in exquisite molecular detail using an ordinary microscope, and to resolve features that would normally be beyond the limits of optics. The technique, called expansion microscopy, involves physically inflating biological tissues using a material more commonly found in baby nappies (diapers). Edward Boyden, a neuroengineer at the Massachusetts Institute of Technology (MIT) in Cambridge, discussed the technique, which he developed with his MIT colleagues Fei Chen and Paul Tillberg, at a conference last month. Prizewinning roots Expansion microscopy is a twist on super-resolution microscopy, which earned three scientists the 2014 Nobel Prize in Chemistry. Both techniques attempt to circumvent a limitation posed by the laws of physics. In 1873, German physicist Ernst Abbe deduced that conventional optical microscopes cannot distinguish objects that are closer together than about 200 nanometres — roughly half the shortest wavelength of visible light. Anything closer than this 'diffraction limit' appears as a blur. © 2015 Nature Publishing Group
Keyword: Brain imaging
Link ID: 20464 - Posted: 01.10.2015
Rose Eveleth Ranking pain isn’t a simple thing. The standard scale that goes from one to 10, often accompanied by smiley faces that become increasingly distressed, has been lampooned by many as being difficult to use. What does it mean to be a five? Or a three? What is that mildly sad frowny face saying? Do you have to be crying for it to really be a 10? And for some people, it’s even harder to put a number to a subjective experience. Patients with autism, for example, often struggle to express the pain they’re feeling. “We do see many members of our community who either experience altered pain perception, or who have difficulties communicating about and reporting pain,” Julia Bascom, the director of programs at the Autistic Self Advocacy Network, told me in an email. “So someone might experience acid reflux not as burning pain, but as pressure in their throat, and then struggle to interpret a numerical pain scale, or not realize they should bring the issue to the attention of those around them—or what words to use to be taken seriously.” Autism can also mean a difficulty interpreting facial expressions, so the happy and sad faces wouldn't be the most helpful visual cues. And some autistic patients aren’t verbal at all. In fact, for a long time, people thought that kids with autism didn’t feel pain at all, because they often didn’t show reactions to it the same way other people do. “They might not understand the words other people use to describe pain, even if they are feeling the exact same sensation, and their outward reactions might seem to indicate much more pain than they are actually feeling,” Bascom said. © 2015 by The Atlantic Monthly Group.
By Nicholas Weiler A friend can make even the shiest creature bold. Rats usually fear strange open spaces, but having a companion by their side makes the rodents more intrepid, scientists report in the current issue of Animal Cognition. Researchers tracked rats’ exploration of a large, unfamiliar room, first alone, then again 2 days later either alone or paired with a familiar cagemate. On their own, rats made short, hesitant forays into the open space before darting back to huddle by the door. Solitary rats’ anxiety in the room didn’t improve on their second visit. But adding a friend, even one who’d never seen the room before, gave the pair the confidence to actively explore, covering 50% more ground and running significantly faster than the control rats. And exploring with company seemed to boost the rats’ sense of security permanently. Placed in the room a third time, once more alone, the socialized rats boldly explored more new places than ever, while solo rats continued to cower. This illustrates that for communal animals like rats—and perhaps humans—friendship can be the best antidote to fear. © 2015 American Association for the Advancement of Scienc
Link ID: 20462 - Posted: 01.10.2015
Sara Reardon Ketamine, a psychoactive ‘party drug’ better known as Special K, has pharmaceutical companies riding high. Used clinically as an anaesthetic in animals and humans, it has proved an extremely effective treatment for depression, bipolar disorder and suicidal behaviour. It also works incredibly fast. Unlike conventional antidepressants, which generally take weeks to start working, ketamine lifts depression in as little as two hours. “It blew the doors off what we thought we knew about depression treatment,” says psychiatrist James Murrough at Mount Sinai Hospital in New York City. Companies are racing to develop patentable forms of the drug, and researchers are battling to understand how it affects the brain. An increasing number of clinicians are prescribing ketamine off-label for their patients, even as some of their colleagues worry that too little is known about its long-term effects. The excitement over ketamine shows how badly new depression drugs are needed, says Thomas Insel, director of the US National Institute of Mental Health (NIMH) in Bethesda, Maryland. Many drug companies have closed their mental-health divisions in the past five years, and there have been no significant advances in medication for depression in decades. Today’s most common antidepressants target the brain’s serotonin or noradrenaline pathways (some target both). Ketamine blocks the signalling molecule NMDA, a component of the glutamate pathway, which is involved in memory and cognition. Before ketamine was studied, no one even knew that the pathway was involved in depression, Murrough says. © 2015 Nature Publishing Group
|By Tori Rodriguez Coffee and tea may do more than just jolt you awake—they could also help keep your brain healthy, according to a slew of recent studies. Researchers have linked these beverages with protection from depression, Alzheimer's disease and Parkinson's disease. One large study investigated the link between depression and the intake of coffee, tea and sweet drinks [see box below]by following more than a quarter of a million older adults for 10 years. Researchers at the National Institutes of Health recorded consumption of each type of beverage in 1995 and 1996 and then compared those figures with participants' self-reported diagnoses of depression after 2000. Results showed that coffee intake was associated with a slightly lower risk for depression, according to a paper published last April in PLOS ONE. The paper found little effect from tea, but other work has shown tea to be protective. A study reported in November 2013 found older Chinese adults who regularly drank any kind of tea had a significantly smaller risk for depression: 21 percent for those who drank tea between one and five days a week and 41 percent for daily drinkers. The researchers also asked about the participants' leisure activities to ensure that the tea, and not teatime socializing, provided the protective effect. Some studies suggest that coffee and tea drinkers have lower rates of cognitive decline, too, but the evidence is mixed. Research in rodents that has focused on specific compounds in coffee and tea supports the idea that some of these chemicals reduce the risk for Alzheimer's and Parkinson's. In one such study, published online last June in Neurobiology of Aging, supplementing rats' diets with a component of coffee called eicosanoyl-5-hydroxytryptamide shielded the animals' brains against the pathological changes typical of Alzheimer's. © 2015 Scientific American,
|William Mullen, Tribune reporter Researchers at Northwestern University say they have discovered a common cause behind the mysterious and deadly affliction of amyotrophic lateral sclerosis, or Lou Gehrig's disease, that could open the door to an effective treatment. Dr. Teepu Siddique, a neuroscientist with Northwestern's Feinberg School of Medicine whose pioneering work on ALS over more than a quarter-century fueled the research team's work, said the key to the breakthrough is the discovery of an underlying disease process for all types of ALS. The discovery provides an opening to finding treatments for ALS and could also pay dividends by showing the way to treatments for other, more common neurodegenerative diseases such as Alzheimer's, dementia and Parkinson's, Siddique said. The Northwestern team identified the breakdown of cellular recycling systems in the neurons of the spinal cord and brain of ALS patients that results in the nervous system slowly losing its ability to carry brain signals to the body's muscular system. Without those signals, patients gradually are deprived of the ability to move, talk, swallow and breathe. "This is the first time we could connect (ALS) to a clear-cut biomedical mechanism," Siddique said. "It has really made the direction we have to take very clear and sharp. We can now test for drugs that would regulate this protein pathway or optimize it, so it functions as it should in a normal state."
Keyword: ALS-Lou Gehrig's Disease
Link ID: 20459 - Posted: 01.08.2015
|By Karen Hopkin Sometimes it’s hard to see the light. Especially if it lies outside the visible spectrum, like x-rays or ultraviolet radiation. But if you long to see the unseeable, you might be interested to hear that under certain conditions people can catch a glimpse of usually invisible infrared light. That’s according to a study in the Proceedings of the National Academy of Sciences. [Grazyna Palczewska et al, Human infrared vision is triggered by two-photon chromophore isomerization] Our eyes are sensitive to elementary particles called photons that have sufficient energy to excite light-sensitive receptor proteins in our retinas. But the photons in infrared radiation don’t have enough oomph. We can detect these lower energy photons using what are sometimes called night-vision goggles or cameras. But the naked eye is usually blind to infrared radiation. But recently researchers in a laser lab noticed that they sometimes saw flashes of light while working with devices that emitted brief infrared pulses. So they filled a test tube with retinal cells and zapped it with their lasers. When the light pulses rapidly enough, the receptors can get hit with two photons at the same time—which supplies enough energy to excite the receptor. This double dose makes the infrared visible. One application of the finding is that it could give doctors a new tool to diagnose diseases of the retina. So they could eyeball trouble before it might otherwise be seen.
Link ID: 20458 - Posted: 01.08.2015
By Virginia Morell Animals that live in larger societies tend to have larger brains. But why? Is it because a larger group size requires members to divide up the labor on tasks, thus causing some individuals to develop specialized brains and neural anatomy? (Compared with most humans, for instance, taxicab drivers have brains that have larger areas that are involved with spatial memory.) Or is it because the challenges of group living—needing to know all the foibles of your neighbors—cause the brains of all members to grow larger? Scientists tested the two hypotheses with wild colonies of acacia ants (Pseudomyrmex spinicola), which make their nests in the hollow spines of acacia trees in Panama. Ant workers at the base of the tree wait to attack intruders, while workers foraging on the leaves (as in the photo above), aren’t as aggressive but are faster at managing the colony’s brood. This division of labor is most marked in larger colonies (those found on larger trees), while workers in smaller colonies do both jobs. The scientists studied 17 colonies of ants and measured the brain volumes of 29 of the leaf ants and 34 of the trunk ants. As the colony size increased, the leaf ants showed a marked increase in the regions of the brain concerned with learning and memory, the scientists report today in the Proceedings of the Royal Society B. But the same neural areas decreased in the trunk ants. Thus, larger societies’ need for specialized workers, some strictly for defense, others for foraging and brood tending—rather than for social masters—seems to be the key to the expanding brain, at least in ants.
Link ID: 20457 - Posted: 01.08.2015
John Markoff MENLO PARK, CALIF. — Ann Lam delicately places a laboratory slide holding a slice of brain from a living human onto a small platform in a room the size of a walk-in refrigerator. She closes a heavy door and turns to a row of computers to monitor her experiments. She is using one of the world’s most sophisticated and powerful microscopes, the Stanford Synchrotron Radiation Lightsource, to learn about the distribution of metals in the brains of epilepsy patients. But she has another reason for being here as well. Traditional techniques for staining brain tissue produce byproducts and waste that are hazardous to the environment. And often, this sort of research is performed on animals, something Dr. Lam insists on avoiding. The radiation that illuminates the Stanford microscope was once a waste product produced by the particle accelerators. Now that it has been harnessed — recycled, in a sense — she is able to use it to examine tissue removed from living human patients, not animals. For Dr. Lam, those are important considerations. Indeed, scientists like her worry that neuroscience has become a dirty business. Too often, they say, labs are stocked with toxic chemicals, dangerous instruments and hapless animal subjects. Funding often comes from the military, and some neuroscientists fear their findings may soon be applied in ways that they never intended, raising moral questions that are seldom addressed. In 2012, Dr. Lam and Dr. Elan Ohayon, her husband, founded the Green Neuroscience Laboratory in a former industrial building in the Convoy District, an up-and-coming San Diego neighborhood. Solar panels rest on the roof, and a garden is lovingly tended on the second floor. © 2015 The New York Times Company