Most Recent Links
Follow us on Facebook and Twitter, or subscribe to our mailing list, to receive news updates. Learn more.
Carl Zimmer Forcing male flies into monogamy has a startling effect: After a few dozen generations, the flies become worse at learning. This discovery, published on Wednesday in the Proceedings of the Royal Society, isn’t a biological excuse for men who have strayed from their significant other. Instead, it’s a tantalizing clue about why intelligence evolved. The new study was carried out by Brian Hollis and Tadeusz J. Kawecki, biologists at the University of Lausanne in Switzerland. They investigated a fly species called Drosophila melanogaster that normally has a very un-monogamous way of life. To find a mate, the male flies seek out females on rotting pieces of fruit. They often engage in battles to chase their rivals away, and then pick a female to court. “The males will do this wing song, where they use one wing or the other to generate a song,” said Dr. Hollis. This wing song may last from 10 minutes to an hour. Virgin females usually accept the overtures. But if a female has just mated, she will reject a new male’s advances. “If a male comes at her from behind and she’s not interested, she’ll kick at him with her rear legs,” said Dr. Hollis. If a couple of days have passed since her last mating, however, the female may choose to mate again. Seven years ago, while he was a graduate student at Florida State University, Dr. Hollis set out to study how the competition among males shapes their evolution. He began breeding two groups of flies — one polygamous, the other monogamous. In 2011, he took his flies to the University of Lausanne, where he met Dr. Kawecki, an expert on learning. The two scientists wondered if the different mating habits of Dr. Hollis’s flies had altered their brains. © 2014 The New York Times Company
Brian Owens The distinctive aroma of goats does more than just make barnyards extra fragrant. Male goats can use their heady scent to make female goats ovulate simply by being near them. Researchers had ascribed this 'male effect' to chemicals known as primer pheromones — a chemical signal that can cause long-lasting physiological responses in the recipient. Examples of primer pheromones are rare in mammals; the male effect in goats and sheep, and a similar effect in mice and rats, where the presence of males can speed up puberty in females, are the only known cases. But exactly what substances are at work and how has remained a mystery. Now, reproductive biologist Yukari Takeuchi from the University of Tokyo and her colleagues have identified a single molecule, known as 4-ethyloctanal, in the cocktail of male goat pheromones that activates the neural pathway that regulates reproduction in females1. ”It has long been thought that pheromones have pivotal roles in reproductive success in mammals, but the mechanisms are scarcely known,” says Takeuchi. The researchers found that male goat pheromones are generally synthesized in the animal's head skin, so they designed a hat containing a material that captured their odorous molecules and placed them on the goats for a week to collect the scent. Analysis of the gases collected identified a range of compounds, many of which were unknown and were not present in castrated males. When exposed to a cocktail of 18 of these chemicals, the brains of female goats showed a sudden increase in the activity of the gonadotropin-releasing hormone (GnRH) pulse generator — the neural regulator of reproduction. © 2014 Nature Publishing Group,
A brain-training video game that improved the vision of college baseball players by as much as two lines on an eye chart has been developed by U.S. researchers. "This is something which I think could help almost anybody," said Aaron Seitz, a neuroscientist at the University of California, Riverside, who the led the research. Players on the university's baseball team improved their visual acuity by 31 per cent after training with the app. And that translated into better performance on the baseball field, where better vision improves the odds of hitting a ball travelling well over 100 km/h. "What we found is they had fewer strikeouts, they were able to create more runs," Seitz told CBC's Quirks & Quarks in an interview that airs Saturday. The players had more runs than predicted even after taking into account the natural improvement that would be expected over the course of the season. Further calculations suggest the improved performance helped the team to win four or five additional games. Following 30 sessions of training with the app, players had better vision, fewer strikeouts, more runs and more wins. But Seitz thinks the app has even more potential to help people with eye conditions such as lazy eye, glaucoma, or age-related macular degeneration. There are 100 million people around the world who have such low vision that glasses don't help, he added. "All that they have to gain is the brain training element.… For these people, there's just really big real-world benefits that could be achieved if we're able to improve their vision."
Brendan Borrell Scientists can now take snapshots of where and how thousands of genes are expressed in intact tissue samples, ranging from a slice of a human brain to the embryo of a fly. The technique, reported today in Science1, can turn a microscope slide into a tool for creating data-rich, three-dimensional maps of how cells interact with one another — a key to understanding the origins of diseases such as cancer. The methodology also has broader applications, enabling researchers to create, for instance, unique molecular ‘barcodes’ to trace connections between cells in the brain, a stated goal of the US National Institutes of Health's Human Connectome Project. Previously, molecular biologists had a limited spatial view of gene expression, the process by which a stretch of double-stranded DNA is turned into single-stranded RNAs, which can in turn be translated into protein products. Researchers could either grind up a hunk of tissue and catalogue all the RNAs they found there, or use fluorescent markers to track the expression of up to 30 RNAs inside each cell of a tissue sample. The latest technique maps up to thousands of RNAs. Mapping the matrix In a proof-of-principle study, molecular biologist George Church of Harvard Medical School in Boston, Massachusetts, and his colleagues scratched a layer of cultured connective-tissue cells and sequenced the RNA of cells that migrated to the wound during the healing process. Out of 6,880 genes sequenced, the researchers identified 12 that showed changes in gene expression, including eight that were known to be involved in cell migration but had not been studied in wound healing, the researchers say. “This verifies that the technique could be used to do rapidly what has taken scientists years of looking at gene products one by one,” says Robert Singer, a molecular cell biologist at Albert Einstein College of Medicine in New York, who was not involved in the study. © 2014 Nature Publishing Group,
Linda Carroll TODAY contributor Insomnia isn’t something that just happens at night. Researchers have now shown that insomniacs have more active brains than sound sleepers, according to a report published Friday in the journal Sleep. That means sleeplessness may, in fact, have its roots in brain wiring that affects the way our minds work, no matter what time of day it is. “We see insomnia now as more of a 24/7 disorder,” said Dr. Rachel Salas, an assistant professor of neurology at the Johns Hopkins University School of Medicine and lead author of the new study. “It’s like a light switch is continually on. So their brains are always running.” Salas originally thought that sound sleepers would be the ones with more alert and plastic brains. (Brain plasticity basically means how neural pathways can be modified by experience or that it is able to adapt or grow.) To prove the theory, Salas set up an experiment that compared 18 chronic insomniacs to 10 sound sleepers. All of the study volunteers were hooked up to a device that sends magnetic waves through the skull and into the brain. Because transcranial magnetic stimulation (TMS) can be aimed a specific site, the researchers were able to target a point in the motor cortex that controls movements of the thumb. Each magnetic pulse sparked an involuntary twitching of the digit. After 65 run-throughs with the TMS, study volunteers were asked to practice moving their thumbs on their own in a manner opposite to the one that was sparked by the TMS. So, for example, if the TMS sent volunteers’ thumbs flicking up and left, they would be asked to wiggle their digits down and right.
Link ID: 19305 - Posted: 03.01.2014
By STEPHEN P. HINSHAW and RICHARD M. SCHEFFLER BERKELEY, Calif. — THE writing is on the chalkboard. Over the next few years, America can count on a major expansion of early childhood education. We embrace this trend, but as health policy researchers, we want to raise a major caveat: Unless we’re careful, today’s preschool bandwagon could lead straight to an epidemic of 4- and 5-year-olds wrongfully being told that they have attention deficit hyperactivity disorder. Introducing millions of 3- to 5-year-olds to classrooms and preacademic demands means that many more distracted kids will undoubtedly catch the attention of their teachers. Sure, many children this age are already in preschool, but making the movement universal and embedding transitional-K programs in public schools is bound to increase the pressure. We’re all for high standards, but danger lurks. The American Academy of Pediatrics now endorses the idea that the diagnosis of A.D.H.D. can and should begin at age 4, before problems accumulate. In fact, Adderall and other stimulants are approved for treatment of attentional issues in children as young as 3. Early intervention for children with A.D.H.D. could provide great relief. Children who go untreated have major difficulties in school and with their peers, and they have higher-than-normal rates of accidents and physical injuries. The problem is that millions of American children have been labeled with A.D.H.D. when they don’t truly have it. Our research has revealed a worrisome parallel between our nation’s increasing push for academic achievement and increased school accountability — and skyrocketing A.D.H.D. diagnoses, particularly for the nation’s poorest children. © 2014 The New York Times Company
Ian Sample, science correspondent Children born to fathers over the age of 45 are at greater risk of developing psychiatric problems and more likely to struggle at school, according to the findings of a large-scale study. The research found that children with older fathers were more often diagnosed with disorders such as autism, psychosis, attention deficit hyperactivity disorder (ADHD), schizophrenia and bipolar disorder. They also reported more drug abuse and suicide attempts, researchers said. The children's difficulties seemed to affect school performance, leading to worse grades at the age of 15 and fewer years in education overall. "We were shocked when we saw the comparisons," said Brian D'Onofrio, the first author of the study at Indiana University in the US. But he added that it was impossible to be sure that older age was to blame for the problems. Scientists have reported links between fathers' age and children's cognitive performance and health before but this study suggests the risks may be more serious than previously thought. The increased risks might be caused by genetic mutations that build up in sperm as men age. Researchers at Indiana University and the Karolinska Institute in Stockholm studied medical and educational records of more than 2.6 million babies born to 1.4 million men. The group amounted to nearly 90% of births in Sweden from 1973 and 2001. Using the records, the scientists added up diagnoses for psychiatric disorders and educational achievements and compared the figures for children born to fathers of different ages. © 2014 Guardian News and Media Limited
By MICHAEL HEDRICK I still remember the first group therapy session I went to after I got out of the hospital. I was 20 and had been diagnosed as schizophrenic after a road trip that took me from Colorado to the United Nations building in New York City, my mind riddled with notions of good and evil, demons and angels, and a determination to save the world. Now I was in something of a state of shock, having come to understand that amid the delusions and paranoia that swarmed through my head I was, in reality, insane. A constant need to move felt like ants crawling over my skin, a side effect of the antipsychotic medications I had been prescribed. Every second of every day, I felt like clawing out my eyes and tearing out my hair because I just couldn’t sit still. I held up my front, though. I smiled when I thought I had to and tried to be nice to people. Laughter, however, was not something that was possible, and wouldn’t be for a long time. The group was a dual-functioning therapy technique to address both mental health issues and drug abuse. I had been assigned to it after disclosing that I had a marijuana habit. The doctors had told me that therapy groups were an integral part of my getting better. I agreed to go only to get out of the hospital prison and back home to my warm bed. I sat in a circle with a melting pot of people. There was the construction worker still wearing dusty boots and clothes splattered with mud, and the depressed sorority girl, makeup and hair still impeccable. The two had formed a friendship over their history with methamphetamine. There was the quiet bipolar Hispanic man who spoke only in short staccato sentences, and the rotund marketing guy who introduced himself by saying his drugs of choice were food, cocaine and marijuana. © 2014 The New York Times Company
Link ID: 19302 - Posted: 02.27.2014
by Helen Thomson People in a vegetative state showed signs of awareness after electric brain stimulation – and minimally conscious people were able to communicate again TALK about an awakening. People who have been in a minimally conscious state for weeks or years have been temporarily roused using mild electrical stimulation. Soon after it was applied to their brains, 15 people with severe brain damage showed signs of consciousness, including moving their hands or following instructions using their eyes. Two people were even able to answer questions for 2 hours before drifting back into their previous uncommunicative state. "I don't want to give people false hope – these people weren't getting up and walking around – but it shows there is potential for the brain to recover functionality, even several years after damage," says Steven Laureys at the University of Liège in Belgium, who led the research. People with severe brain trauma often fall into a coma. If they "awaken", by showing signs of arousal but not awareness, they are said to be in a vegetative state. This can improve to a state of minimal consciousness, where they might show fluctuating signs of awareness, which come and go, but have no ability to communicate. External stimulation of the brain has been shown to increase arousal, awareness and aspects of cognition in healthy people. So Laureys and his colleagues wondered if it would do the same in people with severe brain damage. They used transcranial direct current stimulation (tDCS), which doesn't directly excite the brain, but uses low-level electrical stimulation to make neurons more or less likely to fire. © Copyright Reed Business Information Ltd.
Link ID: 19301 - Posted: 02.27.2014
By JOHN BRANCH Chronic traumatic encephalopathy, the degenerative brain disease linked to repeated blows to the head, has been found posthumously in a 29-year-old former soccer player, the strongest indication yet that the condition is not limited to athletes who played sports known for violent collisions, like football and boxing. Researchers at Boston University and the VA Boston Healthcare System, who have diagnosed scores of cases of C.T.E., said the player, Patrick Grange of Albuquerque, was the first named soccer player found to have C.T.E. On a four-point scale of severity, his disease was considered Stage 2. Soccer is a physical game but rarely a violent one. Players sometimes collide or fall to the ground, but the most repeated blows to the head may come from the act of heading an airborne ball — to redirect it purposely — in games and practices. Grange, who died in April after being found to have amyotrophic lateral sclerosis, was especially proud of his ability to head the ball, said his parents, Mike and Michele. They recalled him as a 3-year-old, endlessly tossing a soccer ball into the air and heading it into a net, a skill that he continued to practice and display in college and in top-level amateur and semiprofessional leagues in his quest to play Major League Soccer. Grange sustained a few memorable concussions, his parents said — falling hard as a toddler, being knocked unconscious in a high school game and once receiving 17 stitches in his head after an on-field collision in college. “He had very extensive frontal lobe damage,” said Dr. Ann McKee, the neuropathologist who performed the brain examination on Grange. “We have seen other athletes in their 20s with this level of pathology, but they’ve usually been football players.” © 2014 The New York Times Company
Keyword: Brain Injury/Concussion
Link ID: 19300 - Posted: 02.27.2014
by Tom Siegfried If freedom is just another word for nothing left to lose, then “free will” is just another phrase for ability to choose. Bad, wasn’t it? But if free will is an illusion, as many scientists and philosophers have argued, then you shouldn’t blame me. On the other hand, I do blame myself. Because like most bloggers, and possibly even the several dozen humans who don’t blog, I think I decided for myself what to write. Besides, as many investigators of this issue have pointed out, it’s not so obvious that free will is illusory now that quantum mechanics has inserted some randomness into nature. Sadly, though, that reasoning doesn’t get you very far. There’s randomness in the quantum world, all right, just like the unpredictable sequence of winning numbers on a roulette wheel. But in the long run all the numbers turn up about equally often. Free will isn’t worth much if you can’t use it to beat a casino. And as MIT physicist Scott Aaronson points out, quantum math is similar: It gives the odds about what various possible things will happen, and those odds are always predicted precisely. The probability distribution of results is always just what the quantum math says it will be. Aaronson doesn’t see any free will there. Still, the free will question has elicited some sophisticated musing from quantum physicists who like to contemplate the interface of mentality and physical reality. It seems reasonable enough to reexamine such an old question in the light of the latest understanding of the universe. It may be that modern physics can offer a perspective giving hope for those who like to make up their own mind. © Society for Science & the Public 2000 - 2013.
Link ID: 19299 - Posted: 02.27.2014
by Emily Sohn Immediately after birth on many dairy farms, baby cows are separated from their mothers and housed in their own pens to protect them from getting sick. Two months later, they join the herd. But early-life isolation may be depriving baby cows of the opportunity to reach their full potential, found a new study. Compared to calves raised in pairs, isolated calves were much slower to learn new things and had a harder time adapting to changes in their environment. Aside from animal welfare concerns, the new findings suggest that dairy farmers have long been overlooking the brain development of their cows by depriving them of social interaction in their early weeks. “Imagine I said that instead of sending your child to kindergarten, I could put him in the classroom one-on-one with the teacher and all the same resources,” said Daniel Weary, a professor of animal welfare and dairy science at the University of British Columbia in Vancouver. “But at the end of the day, if we found that individuals in this system were showing cognitive deficits in relation to other individuals, we would feel bad about that.” For cows, he said, “it means we’re not keeping these animals in an environment that allows them to be what they can be and should be.” © 2014 Discovery Communications, LLC
Keyword: Development of the Brain
Link ID: 19298 - Posted: 02.27.2014
Sara Reardon Two monkeys sit at computer screens, eyeing one another as they wait for a promised reward: apple juice. Each has a choice — it can either select a symbol that results in juice being shared equally, or pick one that delivers most of the juice to itself. But being selfish is risky. If its partner also chooses not to share, neither gets much juice. This game, the ‘prisoner’s dilemma’, is a classic test of strategy that involves the simultaneous evaluation of an opponent’s thinking. Researchers have now discovered — and manipulated — specific brain circuits in rhesus macaques (Macaca mulatta) that seem to be involved in the animals’ choices, and in their assessments of their partners’ choices. Investigating the connections could shed light on how social context affects decision-making in humans, and how disorders that affect social skills, such as autism spectrum disorder, disrupt brain circuitry. “Once we have identified that there are particular neural signals necessary to drive the processes, we can begin to tinker,” says Michael Platt, a neurobiologist at Duke University in Durham, North Carolina. Neurobiologists Keren Haroush and Ziv Williams of Harvard Medical School in Boston, Massachusetts, zoomed in on neural circuits in rhesus macaques by implanting electrode arrays into a brain area called the dorsal anterior cingulate cortex (dACC), which is associated with rewards and decision-making. The arrays recorded the activity of hundreds of individual neurons. When the monkeys played the prisoner’s dilemma (see ‘A juicy experiment’) against a computer program, they rarely chose to cooperate. But when they played with another monkey that they could see, they were several times more likely to choose to share the juice. © 2014 Nature Publishing Group
On 24 February, Uganda’s president, Yoweri Museveni, signed a draconian Anti-Homosexuality Bill into law, after 2 months of declining to do so. Science, he says, changed his mind—in particular, the findings of a special scientific committee his Health Ministry had appointed earlier in the month. “Their unanimous conclusion was that homosexuality, contrary to my earlier thinking, was behavioural and not genetic,” Museveni wrote to President Barack Obama on 18 February, in response to Obama’s pleas that he not sign the bill. “It was learnt and could be unlearnt.” But some scientists on the committee are crying foul, saying that Museveni and his ruling party—Uganda’s National Resistance Movement (NRM)—misrepresented their findings. “They misquoted our report,” says Paul Bangirana, a clinical psychologist at Makerere University in Kampala. “The report does not state anywhere that homosexuality is not genetic, and we did not say that it could be unlearnt.” Two other committee members have now resigned to protest the use of their report to justify the harsh legislation, which mandates life imprisonment for “aggravated homosexuality,” such as sexual acts with a minor, and prison terms of 7 to 14 years for attempted and actual homosexual acts, respectively. The law was first introduced into Uganda’s Parliament in 2009, but withdrawn after widespread objections to provisions that could have included the death penalty. As he signed the new version, passed by Parliament last 20 December, Museveni claimed that “mercenaries” were recruiting young people into gay activities. © 2014 American Association for the Advancement of Science
|By Lila Stanners Beauty seems mysterious and subjective. Scientists have long attempted to explain why the same object can strike some individuals as breathtaking and others as repulsive. Now a study finds that applying stimulation to a certain brain area enhances people's aesthetic appreciation of visual images. First, participants viewed 70 abstract paintings and sketches and 80 representational (realistic) paintings and photographs and rated how much they liked each one. Then they rated a similar set of images after receiving transcranial direct-current stimulation or sham stimulation. Transcranial direct-current stimulation sends small electrical impulses to the brain through electrodes attached to the head. The technique is noninvasive and cannot be felt, so subjects in the trials were not aware when they received real stimulation. The researchers aimed the impulses at the left dorsolateral prefrontal cortex, an area just behind the brow that is known to be a region critical for emotional processing. They found that the stimulation increased participants' appreciation of representational images, according to the study published online in October 2013 inSocial Cognitive and Affective Neuroscience. The scientists believe the stimulation facilitated a shift from object recognition to aesthetic appraisal for the figurative images; the abstract art was probably being processed by a different area of the brain. This study is one of many recent successful attempts at subtly altering cognition with noninvasive brain stimulation. Some experiments have found that stimulating certain areas allows people to solve math problems or puzzles that formerly had them stumped. Other work suggests these techniques can enhance motor learning, helping athletes or musicians improve at a new sport or a new instrument more rapidly. Experts are quick to point out, however, that these effects are modest enhancements at best—thought induction remains firmly in the realm of science fiction. © 2014 Scientific American
Daniel Cressey Researchers have called for a common method of killing zebrafish used in laboratories to be abandoned amid growing evidence that it causes unnecessary suffering. The anaesthetic MS-222, which can be added to tanks to cause overdose, seems to distress the fish, two separate studies have shown. The studies’ authors propose that alternative anaesthetics or methods should be used instead. “These two studies — carried out independently — use different methodologies to reach the same conclusion: zebrafish detect and avoid MS-222 in the water,” says Stewart Owen, a senior environmental scientist at AstraZeneca’s Brixham Environmental Laboratory in Brixham, UK, and a co-author of one of the studies. “As this is a clear aversive response, as a humane choice, one would no longer use this agent for routine zebrafish anaesthesia.” The use of zebrafish (Danio rerio) in research has skyrocketed in recent years as scientists have sought alternatives to more controversial animal models, such as mammals. The fish are cheap and easy to keep, and although no firm data on numbers have been collected, millions are known to be housed in laboratories around the world. Nearly all will eventually be killed. MS-222 (ethyl 3-aminobenzoate methanesulphate, also known as TMS) is one of the agents most frequently used to kill the creatures. It is listed as an acceptable method of euthanasia by many institutions, and also by societies such as the American Veterinary Medical Association. But the study by Owen and his co-authors, published last year (G. D. Readman et al. PLoS ONE 8, e73773; 2013), and the second study, published earlier this month by Daniel Weary and his colleagues at the University of British Columbia in Vancouver, Canada (D. Wong et al. PLoS ONE 9, e88030; 2014), show that zebrafish seem to find the chemical distressing. The research should fundamentally change the practice, say the authors of both papers. © 2014 Nature Publishing Group
Keyword: Pain & Touch
Link ID: 19294 - Posted: 02.26.2014
By Michelle Roberts Health editor, BBC News online Doctors have devised a new way to treat amputees with phantom limb pain. Using computer-generated augmented reality, the patient can see and move a virtual arm controlled by their stump. Electric signals from the muscles in the amputated limb "talk" to the computer, allowing real-time movement. Amputee Ture Johanson says his pain has reduced dramatically thanks to the new computer program, which he now uses regularly in his home. He now has periods when he is free of pain and he is no longer woken at night by intense periods of pain. Mr Johanson, who is 73 and lives in Sweden, lost half of his right arm in a car accident 48 years ago. After a below-elbow amputation he faced daily pain and discomfort emanating from his now missing arm and hand. Over the decades he has tried numerous therapies, including hypnosis, to no avail. Within weeks of starting on the augmented reality treatment in Max Ortiz Catalan's clinic at Chalmers University of Technology, his pain has now eased. "The pain is much less now. I still have it often but it is shorter, for only a few seconds where before it was for minutes. BBC © 2014
By Deborah Kotz / Globe Staff Obesity rates plummeted among preschool children in the past decade, from nearly 14 percent to just over 8 percent in 2011-12, according to a new federal government analysis that was hailed by one researcher as a “glimmer of hope.” But the campaign to combat the nation’s obesity epidemic has had no success with adults and older children: Americans remain just as overweight as ever, with two out of three adults at an unhealthy weight and more than one out of three obese in 2011-12, the latest years for which statistics were available. The study, published Tuesday in the Journal of the American Medical Association, examined annual government health and nutrition surveys that sampled more than 9,000 Americans of all ages. Despite the gains for toddlers, the study found that overall among children under age 20, 17 percent were at the extreme obese end of the weight spectrum. Nearly one-third of kids remain either overweight or obese—nearly triple the rate of 50 years ago—which pediatricians blame for the sharp rise in type 2 diabetes, high blood pressure, and high cholesterol levels in children. Rates actually increased in one group: Women over age 60 experienced a rise in obesity from just under 32 percent 10 years ago to over 38 percent in 2011-2012. “Obesity rates haven’t changed for most Americans, but there was a glimmer of hope in preschoolers,” said study leader Cynthia Ogden, an epidemiologist at the federal Centers for Disease Control and Prevention’s National Center for Health Statistics. © 2014 Boston Globe Media Partners, LLC
Link ID: 19292 - Posted: 02.26.2014
By JAMES GORMAN SEATTLE — When Clay Reid decided to leave his job as a professor at Harvard Medical School to become a senior investigator at the Allen Institute for Brain Science in Seattle in 2012, some of his colleagues congratulated him warmly and understood right away why he was making the move. Others shook their heads. He was, after all, leaving one of the world’s great universities to go to the academic equivalent of an Internet start-up, albeit an extremely well- financed, very ambitious one, created in 2003 by Paul Allen, a founder of Microsoft. Still, “it wasn’t a remotely hard decision,” Dr. Reid said. He wanted to mount an all-out investigation of a part of the mouse brain. And although he was happy at Harvard, the Allen Institute offered not only great colleagues and deep pockets, but also an approach to science different from the classic university environment. The institute was already mapping the mouse brain in fantastic detail, and specialized in the large-scale accumulation of information in atlases and databases available to all of science. Now, it was expanding, and trying to merge its semi-industrial approach to data gathering with more traditional science driven by individual investigators, by hiring scientists like Christof Koch from the California Institute of Technology as chief scientific officer in 2011 and Dr. Reid. As a senior investigator, he would lead a group of about 100, and work with scientists, engineers and technicians in other groups. Without the need to apply regularly for federal grants, Dr. Reid could concentrate on one piece of the puzzle of how the brain works. He would try to decode the workings of one part of the mouse brain, the million neurons in the visual cortex, from, as he puts it, “molecules to behavior.” © 2014 The New York Times Company
Link ID: 19291 - Posted: 02.25.2014
|By Beth Skwarecki Prions, the protein family notorious for causing "mad cow" and neurodegenerative diseases like Parkinson's, can play an important role in healthy cells. "Do you think God created prions just to kill?" mused Nobel laureate Eric Kandel. "These things must have evolved initially to have a physiological function." His work on memory helped reveal that animals make and use prions in their nervous systems as part of an essential function: stabilizing the synapses that constitute long-term memories. These natural prions aren't infectious but on a molecular level they chain up exactly the same way as their disease-causing brethren. (Some researchers call them "prionlike" to avoid confusion.) This week, work from neuroscientist Kausik Si of the Stowers Institute for Medical Research, one of Kandel's former students, shows that the prion's action is tightly controlled by the cell, and can be turned on when a new long-term memory needs to be formed. Prions are proteins with two unusual properties: First, they can switch between two possible shapes, one that is stable on its own and an alternate conformation that can form chains. Second, the chain-forming version has to be able to trigger others to change shape and join the chain. Say that in the normal version the protein is folded so that one portion of the protein structure—call it "tab A"—fits into its own "slot B." In the alternate form, though, tab A is available to fit into its neighbor's slot B. That means the neighbor can do the same thing to the next protein to come along, forming a chain or clump that can grow indefinitely. © 2014 Scientific American,