Chapter 17. Learning and Memory

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By Jessica Hamzelou You’ve got a spare hour before a big exam. How should you spend it? It seems napping is just as effective as revising, and could even have a longer-lasting impact. Repeatedly revising information to learn it makes sense. “Any kind of reactivation of a memory trace will lead to it being strengthened and reconsolidated,” says James Cousins at the Duke-NUS Medical School in Singapore. “With any memory, the more you recall it, the stronger the memory trace.” However, sleep is also thought to be vital for memory. A good night’s sleep seems to help our brains consolidate what we’ve learned in the day, and learning anything when you’re not well rested is tricky. Many people swear by a quick afternoon kip. So if you’ve got an hour free, is it better to nap or revise? Cousins, along with Michael Chee and their colleagues, also at Duke-NUS Medical School, set out to compare the two options. The team mocked-up a real student experience, and had 72 volunteers sit through presentations of about 12 different species of ants and crabs. The participants were asked to learn all about these animals, including their diets and habitats, for example. After 80 minutes of this, the students were given an hour to either watch a film, have a nap, or revise what they had just learned. After this hour, they had another 80 minutes of learning. Then they had to sit an exam in which they were asked 360 questions about the ants and the crabs. “The napping group got the best scores,” says Cousins, whose work was presented at the Society for Neuroscience annual meeting in San Diego, California on Tuesday. © Copyright Reed Business Information Ltd.

Keyword: Sleep; Learning & Memory
Link ID: 22871 - Posted: 11.16.2016

Kathleen Taylor The global rise in dementia should surprise no one. The figures — such as the 9.9 million new diagnoses each year — have been known for decades. As slow as we are to accept such vast changes on a personal, societal and political level, so research is slow to uncover why our brains become fragile with age. Neuroscientist and writer Kathleen Taylor's The Fragile Brain is about that research. But it is much more than a simple reflection on the best published hypotheses. Taylor has crafted a personal, astonishingly coherent review of our current state of knowledge about the causes of Alzheimer's disease and dementia, as well as possible solutions, from lifestyle adjustments to drug developments. Filled with elegant metaphors, her study covers the detail of molecular biology and larger-scale analysis, including epidemiological observations and clinical studies. It extends to dementia due to multiple sclerosis, stroke and encephalitis. For instance, some 5–30% of people who have a first stroke develop dementia. But the book's focus is Alzheimer's disease, and rightly so: it is what up to 80% of people with dementia are diagnosed with. Taylor begins with a shocking juxtaposition, setting the costs of age-related disorders and of dementia alongside the scarcity in funding. In Britain, Australia and the United States, for example, funding for dementia research is a fraction of that for cancer — in the United States, just 18%. She contextualizes with reflections on the history of dementia research, deftly unravelling the roles of pioneering scientists Alois Alzheimer, Franz Nissl and Emil Kraepelin in describing the condition. © 2016 Macmillan Publishers Limited,

Keyword: Alzheimers; Learning & Memory
Link ID: 22851 - Posted: 11.10.2016

By Marian Vidal-Fernandez, Ana Nuevo-Chiquero, The title of this article might trigger self-satisfied smiles among first-borns, and some concerns among the rest of us. Many studies show children born earlier in the family enjoy better wages and more education, but until now we didn’t really know why. Our recently published findings are the first to suggest advantages of first born siblings start very early in life—around zero to three years old! We observe parents changing their behaviour as new children are born, and offering less cognitive stimulation to children of higher birth order. It now seems clear that for those born and raised in high-income countries such as the United States, the UK and Norway, earlier-born children enjoy higher wages and education as adults—known as the “birth order effect”. Comparing two siblings, the greater the difference in their birth order, the greater the relative benefit to the older child. However, to date we’ve had no evidence that explains where such differences come from. We know it’s not an effect of family size, because the effect remains when comparing siblings within the same family and families with the same number of children. While it makes sense that parents earn more money and gain experience as they get older and have more children, they also need to divide their economic resources and attention among any children that arrive after the first born. We wondered where in childhood these differences began, and what the cause or causes might be. © 2016 Scientific American,

Keyword: Development of the Brain; Learning & Memory
Link ID: 22835 - Posted: 11.05.2016

Laura Sanders A protein that can switch shapes and accumulate inside brain cells helps fruit flies form and retrieve memories, a new study finds. Such shape-shifting is the hallmark move of prions — proteins that can alternate between two forms and aggregate under certain conditions. In fruit flies’ brain cells, clumps of the prionlike protein called Orb2 stores long-lasting memories, report scientists from the Stowers Institute for Medical Research in Kansas City, Mo. Figuring out how the brain forms and calls up memories may ultimately help scientists devise ways to restore that process in people with diseases such as Alzheimer’s. The new finding, described online November 3 in Current Biology, is “absolutely superb,” says neuroscientist Eric Kandel of Columbia University. “It fills in a lot of missing pieces.” People possess a version of the Orb2 protein called CPEB, a commonality that suggests memory might work in a similar way in people, Kandel says. It’s not yet known whether people rely on the prion to store long-term memories. “We can’t be sure, but it’s very suggestive,” Kandel says. When neuroscientist Kausik Si and colleagues used a genetic trick to inactivate Orb2 protein, male flies were worse at remembering rejection. These lovesick males continued to woo a nonreceptive female long past when they should have learned that courtship was futile. In different tests, these flies also had trouble remembering that a certain odor was tied to food. |© Society for Science & the Public 2000 - 2016. All rights reserved.

Keyword: Learning & Memory; Prions
Link ID: 22833 - Posted: 11.04.2016

By Virginia Morell Human hunters may be making birds smarter by inadvertently shooting those with smaller brains. That’s the conclusion of a new study, which finds that hunting may be exerting a powerful evolutionary force on bird populations in Denmark, and likely wherever birds are hunted. But the work also raises a red flag for some researchers who question whether the evolution of brain size can ever be tied to a single factor. The new work “broadens an emerging view that smarts really do matter in the natural, and increasingly human-dominated, world,” says John Marzluff, a wildlife biologist and expert on crow cognition at the University of Washington in Seattle who was not involved with the work. Hunting and fishing are known to affect many animal populations. For instance, the pike-perch in the Finnish Archipelago Sea has become smaller over time thanks to fishing, which typically removes the largest individuals from a population. This pressure also causes fish to reach sexual maturity earlier. On land, natural predators like arctic foxes and polar bears can also drive their prey species to become smarter because predators are most likely to catch those with smaller brains. For instance, a recent study showed that common eiders (maritime ducks) that raise the most chicks also have the largest heads and are better at forming protective neighborhood alliances than ducks with smaller heads—and presumably, brains. © 2016 American Association for the Advancement of Science

Keyword: Learning & Memory; Evolution
Link ID: 22820 - Posted: 11.02.2016

Bruce Bower Many preschoolers take a surprisingly long and bumpy mental path to the realization that people can have mistaken beliefs — say, thinking that a ball is in a basket when it has secretly been moved to a toy box. Traditional learning curves, in which kids gradually move from knowing nothing to complete understanding, don’t apply to this landmark social achievement and probably to many other types of learning, a new study concludes. Kids ranging in age from 3 to 5 often go back and forth between passing and failing false-belief tests for several months to more than one year, say psychologist Sara Baker of the University of Cambridge and her colleagues. A small minority of youngsters jump quickly from always failing to always passing these tests, the scientists report October 20 in Cognitive Psychology. “If these results are replicated, it will surprise a lot of researchers that there is such a low level of sudden insight into false beliefs,” says psychologist Malinda Carpenter, currently at the Max Planck Institute for Evolutionary Anthropology in Leipzig. Early childhood researchers generally assume that preschoolers either pass or fail false-belief tests, with a brief transition between the two, explains Carpenter, who did not participate in the new study. Grasping that others sometimes have mistaken beliefs is a key step in social thinking. False-belief understanding may start out as something that can be indicated nonverbally but not described. Human 2-year-olds and even chimpanzees tend to look toward spots where a person would expect to find a hidden item that only the children or apes have seen moved elsewhere (SN Online: 10/6/16). © Society for Science & the Public 2000 - 2016

Keyword: Learning & Memory; Development of the Brain
Link ID: 22816 - Posted: 11.01.2016

By Ruth Williams .Newly made cells in the brains of mice adopt a more complex morphology and connectivity when the animals encounter an unusual environment than if their experiences are run-of-the-mill. Researchers have now figured out just how that happens. According to a study published today (October 27) in Science, a particular type of cell—called an interneuron—in the hippocampus processes the animals’ experiences and subsequently shapes the newly formed neurons. “We knew that experience shapes the maturation of these new neurons, but what this paper does is it lays out the entire circuit through which that happens,” said Heather Cameron, a neuroscientist at the National Institute of Mental Health in Bethesda who was not involved with the work. “It’s a really nicely done piece of work because they go step-by-step and show all of the cells that are involved and how they’re connected.” Most of the cells in the adult mammalian brain are mature and don’t divide, but in a few regions, including an area of the hippocampus called the dentate gyrus, neurogenesis occurs. The dentate gyrus is thought to be involved in the formation of new memories. In mice, for instance, exploring novel surroundings electrically activates the dentate gyrus and can affect the production, maturation, and survival of the newly born cells. Now, Alejandro Schinder and his team at the Leloir Institute in Buenos Aires, Argentina, have investigated the process in detail. © 1986-2016 The Scientist

Keyword: Neurogenesis; Learning & Memory
Link ID: 22804 - Posted: 10.29.2016

By Catherine Caruso Babies and children undergo massive brain restructuring as they mature, and for good reason—they have a whole world of information to absorb during their sprint toward adulthood. This mental renovation doesn’t stop there, however. Adult brains continue to produce new cells and restructure themselves throughout life, and a new study in mice reveals more about the details of this process and the important role environmental experience plays. Through a series of experiments, researchers at the Leloir Institute in Buenos Aires showed that when adult mice are exposed to stimulating environments, their brains are able to more quickly integrate new brain cells into existing neural networks through a process that involves new and old cells connecting to one another via special helper cells called interneurons. The adult mammalian brain, long believed to lack the capacity to make new cells, has two main areas that continuously produce new neurons throughout life. One of these areas, the hippocampus (which is involved in memory, navigation, mood regulation and stress response) produces new neurons in a specialized region called the dentate gyrus. Many previous studies have focused on how the dentate gyrus produces new neurons and what happens to these neurons as they mature, but Alejandro Schinder and his colleagues at Leloir wanted to go one step further and understand how new neurons produced by the dentate gyrus are incorporated into the existing neural networks of the brain, and whether environment affects this process. © 2016 Scientific American

Keyword: Learning & Memory; Development of the Brain
Link ID: 22802 - Posted: 10.28.2016

By Steven C. Pan A good night’s sleep can be transformative. Among its benefits are improved energy and mood, better immune system functioning and blood sugar regulation, and greater alertness and ability to concentrate. Given all of these benefits, the fact that a third of the human lifespan is spent sleeping makes evolutionary sense. However, sleep appears to have another important function: helping us learn. Across a plethora of memory tasks—involving word lists, maze locations, auditory tones, and more—going to sleep after training yields better performance than remaining awake. This has prompted many sleep researchers to reach a provocative conclusion: beyond merely supporting learning, sleep is vital, and perhaps even directly responsible, for learning itself. Recent discoveries from neuroscience provide insights into that possibility. Sleep appears to be important for long-term potentiation, a strengthening of signals between neurons that is widely regarded as a mechanism of learning and memory. Certain memories acquired during the day appear to be reactivated and “replayed” in the brain during sleep, which may help make them longer lasting. In some instances the amount of improvement that occurs on memory tasks positively correlates with the length of time spent in certain stages of sleep. These and other findings are generating great excitement among sleep researchers, as well as prompting heated debates about the degree to which sleep may or may not be involved in learning. To date, most sleep and learning research has focused on recall, which is the capacity to remember information. However, new research by Stéphanie Mazza and colleagues at the University of Lyon, recently published in the journal Psychological Science,suggests another potential benefit of sleep: improved relearning. © 2016 Scientific American

Keyword: Sleep; Learning & Memory
Link ID: 22787 - Posted: 10.26.2016

By Agata Blaszczak-Boxe Some rodents have a sweet tooth. And sometimes, you need to get crafty to reach your sugar fix. Rats have been filmed for the first time using hooked tools to get chocolate cereal – a manifestation of their critter intelligence. Akane Nagano and Kenjiro Aoyama, of Doshisha University in Kyotanabe, Japan, placed eight brown rats in a transparent box and trained them to pull small hooked tools to obtain the cereal that was otherwise beyond their reach. In one experiment they gave them two similar hooked tools, one of which worked well for the food retrieval task, and the other did not. The rats quickly learned to choose the correct tool for the job, selecting it 95 per cent of the time. The experiments showed that the rats understood the spatial arrangement between the food and the tool. The team’s study is the first to demonstrate that rats are able to use tools, says Nagano. The rats did get a little confused in the final experiment. When the team gave them a rake that looked the part but with a bottom was too soft and flimsy to move the cereal, they still tried to use it as much as the working tool that was also available. But, says Nagano, it is possible their eyesight was simply not good enough for them to tell that the flimsy tool wasn’t up to the task. The rodents’ crafty feat places them in the ever-growing club of known tool-using animals such as chimps, bearded capuchin monkeys, New Caledonian crows, alligators and even some fish. © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory; Intelligence
Link ID: 22774 - Posted: 10.22.2016

By Gareth Cook According to the American Psychiatric Association, about 5 percent of American children suffer from Attention Deficit Hyperactivity Disorder (ADHD), yet the diagnosis is given to some 15 percent of American children, many of whom are placed on powerful drugs with lifelong consequences. This is the central fact of the journalist Alan Schwarz’s new book, ADHD Nation. Explaining this fact—how it is that perhaps two thirds of the children diagnosed with ADHD do not actually suffer from the disorder—is the book’s central mystery. The result is a damning indictment of the pharmaceutical industry, and an alarming portrait of what is being done to children in the name of mental health. What prompted you to write this book? In 2011, having spent four years exposing the dangers of concussions in the National Football League and youth sports for The New York Times, I wanted another project. I had heard that high school students in my native Westchester County (just north of New York City) were snorting Adderall before the S.A.T.'s to focus during the test. I was horrified and wanted to learn more. I saw it not as a "child psychiatry" story, and not as a "drug abuse" story, but one about academic pressure and the demands our children feel they're under. When I looked deeper, it was obvious that our nationwide system of ADHD treatment was completely scattershot—basically, many doctors were merely prescribing with little thought into whether a kid really had ADHD or not, and then the pills would be bought and sold among students who had no idea what they were messing with. I asked the ADHD and child-psychiatry establishment about this, and they denied it was happening. They denied that there were many false diagnoses. They denied that teenagers were buying and selling pills. They denied that the national diagnosis rates reported by the C.D.C.—then 9.5 percent of children aged 4-17, now 11 percent and still growing—were valid. They basically denied that anything about their world was malfunctioning at all. In the end, they doth protest too much. I wrote about 10 front-page stories for The New York Times on the subject from 2012-2014. © 2016 Scientific American,

Keyword: ADHD; Drug Abuse
Link ID: 22747 - Posted: 10.12.2016

Erin Ross The teenage brain has been characterized as a risk-taking machine, looking for quick rewards and thrills instead of acting responsibly. But these behaviors could actually make teens better than adults at certain kinds of learning. "In neuroscience, we tend to think that if healthy brains act in a certain way, there should be a reason for it," says Juliet Davidow, a postdoctoral researcher at Harvard University in the Affective Neuroscience and Development Lab and the lead author of the study, which was published Wednesday in the journal Neuron. But scientists and the public often focus on the negatives of teen behavior, so she and her colleagues set out to test the hypothesis that teenagers' drive for rewards, and the risk-taking that comes from it, exist for a reason. When it comes to what drives reward-seeking in teens, fingers have always been pointed at the striatum, a lobster-claw-shape structure in the brain. When something surprising and good happens — say, you find $20 on the street — your body produces the pleasure-related hormone dopamine, and the striatum responds. "Research shows that the teenage striatum is very active," says Davidow. This suggests that teens are hard-wired to seek immediate rewards. But, she adds, it's also shown that their prefrontal cortex, which helps with impulse control, isn't fully developed. Combined, these two things have given teens their risky rep. But the striatum isn't just involved in reward-seeking. It's also involved in learning from rewards, explains Daphna Shohamy, a cognitive neuroscientist at the Zuckerman Mind Brain Behavior Institute at Columbia University who worked on the study. She wanted to see if teenagers would be better at this type of learning than adults would. © 2016 npr

Keyword: Development of the Brain; Learning & Memory
Link ID: 22738 - Posted: 10.10.2016

Richard A. Friedman There’s a reason adults don’t pick up Japanese or learn how to kite surf. It’s ridiculously hard. In stark contrast, young people can learn the most difficult things relatively easily. Polynomials, Chinese, skateboarding — no problem! Neuroplasticity — the brain’s ability to form new neural connections and be influenced by the environment — is greatest in childhood and adolescence, when the brain is still a work in progress. But this window of opportunity is finite. Eventually it slams shut. Or so we thought. Until recently, the conventional wisdom within the fields of neuroscience and psychiatry has been that development is a one-way street, and once a person has passed through his formative years, experiences and abilities are very hard, if not impossible, to change. What if we could turn back the clock in the brain and recapture its earlier plasticity? This possibility is the focus of recent research in animals and humans. The basic idea is that during critical periods of brain development, the neural circuits that help give rise to mental states and behaviors are being sculpted and are particularly sensitive to the effects of experience. If we can understand what starts and stops these periods, perhaps we can restart them. Think of the brain’s sensitive periods as blown glass: The molten glass is very malleable, but you have a relatively brief time before it cools and becomes crystalline. Put it back into the furnace, and it can once again change shape. © 2016 The New York Times Company

Keyword: Development of the Brain; Learning & Memory
Link ID: 22737 - Posted: 10.10.2016

Dean Burnett Throughout history, people have always worried about new technologies. The fear that the human brain cannot cope with the onslaught of information made possible by the latest development was first voiced in response to the printing press, back in the sixteenth century. Swap “printing press” for “internet” and you have the exact same concerns today, regularly voiced in the mainstream media, and usually focused on children. But is there any legitimacy to these claims? Or are they just needless scaremongering? There are several things to bear in mind when considering how our brains deal with the internet. The human brain is always dealing with a constant stream of rich information - that’s what the real world is First, don’t forget that “the internet” is a very vague term, given that it contains so many things across so many formats. You could, for instance, develop a gambling addiction via online casinos or poker sites. This is an example of someone’s brain being negatively affected via the internet, but it would be difficult to argue that the internet is the main culprit, any more than a gambling addiction obtained via a real world casino can be blamed on “buildings”; it’s just the context in which the problem occurred. However, the internet does give us a far more direct, constant and wide ranging access to information than pretty much anything else in human history. So how could, or does, this affect us and our brains? © 2016 Guardian News and Media Limited

Keyword: Learning & Memory
Link ID: 22736 - Posted: 10.10.2016

/ By Seth Mnookin When Henry Molaison died at a Connecticut nursing home in 2008, at the age of 82, a front-page obituary in The New York Times called him “the most important patient in the history of brain science.” It was no exaggeration: Much of what we know about how memory works is derived from experiments on Molaison, a patient with severe epilepsy who in 1953 had undergone an operation that left him without medial temporal lobes and the ability to form new memories. The operation didn’t completely stop Molaison’s seizures — the surgeon, William Beecher Scoville, had done little more than guess at the locus of his affliction — but by chance, it rendered him a near-perfect research subject. Not only could postoperative changes in his behavior be attributed to the precise area of his brain that had been removed, but the fact that he couldn’t remember what had happened 30 seconds earlier made him endlessly patient and eternally willing to endure all manner of experiments. It didn’t take long for those experiments to upend our understanding of the human brain. By the mid-1950s, studies on Molaison (known until his death only as Patient H.M.) had shown that, contrary to popular belief, memories were created not in the brain as a whole, but in specific regions — and that different types of memories were formed in different ways. Molaison remained a research subject until his death, and for the last 41 years of his life, the person who controlled access to him, and was involved in virtually all the research on him, was an MIT neuroscientist named Suzanne Corkin. Copyright 2016 Undark

Keyword: Learning & Memory
Link ID: 22729 - Posted: 10.05.2016

Jon Hamilton Want to be smarter? More focused? Free of memory problems as you age? If so, don't count on brain games to help you. That's the conclusion of an exhaustive evaluation of the scientific literature on brain training games and programs. It was published Monday in the journal Psychological Science in the Public Interest. "It's disappointing that the evidence isn't stronger," says Daniel Simons, an author of the article and a psychology professor at the University of Illinois at Urbana-Champaign. "It would be really nice if you could play some games and have it radically change your cognitive abilities," Simons says. "But the studies don't show that on objectively measured real-world outcomes." The evaluation, done by a team of seven scientists, is a response to a very public disagreement about the effectiveness of brain games, Simons says. In October 2014, more than 70 scientists published an open letter objecting to marketing claims made by brain training companies. Pretty soon, another group, with more than 100 scientists, published a rebuttal saying brain training has a solid scientific base. "So you had two consensus statements, each signed by many, many people, that came to essentially opposite conclusions," Simons says. © 2016 npr

Keyword: Learning & Memory
Link ID: 22727 - Posted: 10.05.2016

By Deborah R. Glasofer, Joanna Steinglass Every day on the dot of noon, Jane* would eat her 150-calorie lunch: nonfat yogurt and a handful of berries. To eat earlier, she felt, would be “gluttonous.” To eat later would disrupt the dinner ritual. Jane's eating initially became more restrictive in adolescence, when she worried about the changes her body was undergoing in the natural course of puberty. When she first settled on her lunchtime foods and routine—using a child-size spoon to “make the yogurt last” and sipping water between each bite—she felt accomplished. Jane enjoyed her friends' compliments about her “incredible willpower.” In behavioral science terms, her actions were goal-directed, motivated by achieving a particular outcome. In relatively short order, she got the result she really wanted: weight loss. Years later Jane, now in her 30s and a newspaper reporter, continued to eat the same lunch in the same way. Huddled over her desk in the newsroom, she tried to avoid unwanted attention and feared anything that might interfere with the routine. She no longer felt proud of her behavior. Her friends stopped complimenting her “self-control” years ago, when her weight plummeted perilously low. So low that she has had to be hospitalized on more than one occasion. The longed-for weight loss did not make her feel better about herself or her appearance. Jane's curly hair, once shiny and thick, dulled and thinned; her skin and eyes lost their brightness. There were other costs as well—to her relationships, to her career. Instead of dreaming about a great romance, Jane would dream of the cupcakes she could not let herself have at her niece's birthday party. Instead of thinking about the best lead for her next story, she obsessed over calories and exercise. © 2016 Scientific American

Keyword: Anorexia & Bulimia; Attention
Link ID: 22713 - Posted: 09.30.2016

By CATHERINE SAINT LOUIS Increasing numbers of children have high blood pressure, largely as a consequence of their obesity. A growing body of evidence suggests that high blood pressure may impair children’s cognitive skills, reducing their ability to remember, pay attention and organize facts. In the most comprehensive study to date, published on Thursday in The Journal of Pediatrics, 75 children ages 10 to 18 with untreated high blood pressure performed worse on several tests of cognitive function, compared with 75 peers who had normal blood pressure. The differences were subtle, and the new research does not prove that high blood pressure diminishes cognitive skills in children. Still, the findings set off alarm bells among some experts. “This study really shows there are some differences,” said Dr. David B. Kershaw, the director of pediatric nephrology at C. S. Mott Children’s Hospital at the University of Michigan, who was not involved with the research. “This was not just random chance.” Dr. Marc B. Lande, a professor of pediatric nephrology at the University of Rochester Medical Center, and his colleagues had children tested at four sites in three states, matching those with and without high blood pressure by age, maternal education, race, obesity levels and other factors. The researchers excluded children with learning disabilities and sleep problems, which can affect cognitive skills. Children with elevated blood pressure performed worse than their peers on tests of memory, processing speed and verbal skills, the researchers found. But all the scores were still in the normal range. Because of increased obesity, elevated blood pressure, also called hypertension, is no longer rare in children, though it is underdiagnosed. In a recent survey, about 3.5 percent of 14,187 children ages 3 to 18 had hypertension. © 2016 The New York Times Company

Keyword: ADHD; Obesity
Link ID: 22709 - Posted: 09.29.2016

By Edd Gent, A brain-inspired computing component provides the most faithful emulation yet of connections among neurons in the human brain, researchers say. The so-called memristor, an electrical component whose resistance relies on how much charge has passed through it in the past, mimics the way calcium ions behave at the junction between two neurons in the human brain, the study said. That junction is known as a synapse. The researchers said the new device could lead to significant advances in brain-inspired—or neuromorphic—computers, which could be much better at perceptual and learning tasks than traditional computers, as well as far more energy efficient. "In the past, people have used devices like transistors and capacitors to simulate synaptic dynamics, which can work, but those devices have very little resemblance to real biological systems. So it's not efficient to do it that way, and it results in a larger device area, larger energy consumption and less fidelity," said study leader Joshua Yang, a professor of electrical and computer engineering at the University of Massachusetts Amherst. [10 Things You Didn't Know About the Brain] Previous research has suggested that the human brain has about 100 billion neurons and approximately 1 quadrillion (1 million billion) synapses. A brain-inspired computer would ideally be designed to mimic the brain's enormous computing power and efficiency, scientists have said. © 2016 Scientific American

Keyword: Robotics; Learning & Memory
Link ID: 22705 - Posted: 09.28.2016

By GRETCHEN REYNOLDS Before you skip another workout, you might think about your brain. A provocative new study finds that some of the benefits of exercise for brain health may evaporate if we take to the couch and stop being active, even just for a week or so. I have frequently written about how physical activity, especially endurance exercise like running, aids our brains and minds. Studies with animals and people show that working out can lead to the creation of new neurons, blood vessels and synapses and greater overall volume in areas of the brain related to memory and higher-level thinking. Presumably as a result, people and animals that exercise tend to have sturdier memories and cognitive skills than their sedentary counterparts. Exercise prompts these changes in large part by increasing blood flow to the brain, many exercise scientists believe. Blood carries fuel and oxygen to brain cells, along with other substances that help to jump-start desirable biochemical processes there, so more blood circulating in the brain is generally a good thing. Exercise is particularly important for brain health because it appears to ramp up blood flow through the skull not only during the actual activity, but throughout the rest of the day. In past neurological studies, when sedentary people began an exercise program, they soon developed augmented blood flow to their brains, even when they were resting and not running or otherwise moving. But whether those improvements in blood flow are permanent or how long they might last was not clear. So for the new study, which was published in August in Frontiers in Aging Neuroscience, researchers from the department of kinesiology at the University of Maryland in College Park decided to ask a group of exceedingly fit older men and women to stop exercising for awhile. © 2016 The New York Times Company

Keyword: Learning & Memory; Development of the Brain
Link ID: 22704 - Posted: 09.28.2016