Chapter 17. Learning and Memory

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


Links 1 - 20 of 1259

Jon Hamilton Researchers have identified a substance in muscles that helps explain the connection between a fit body and a sharp mind. When muscles work, they release a protein that appears to generate new cells and connections in a part of the brain that is critical to memory, a team reports Thursday in the journal Cell Metabolism. The finding "provides another piece to the puzzle," says Henriette van Praag, an author of the study and an investigator in brain science at the National Institute on Aging. Previous research, she says, had revealed factors in the brain itself that responded to exercise. The discovery came after van Praag and a team of researchers decided to "cast a wide net" in searching for factors that could explain the well-known link between fitness and memory. They began by looking for substances produced by muscle cells in response to exercise. That search turned up cathepsin B, a protein best known for its association with cell death and some diseases. Experiments showed that blood levels of cathepsin B rose in mice that spent a lot of time on their exercise wheels. What's more, as levels of the protein rose, the mice did better on a memory test in which they had to swim to a platform hidden just beneath the surface of a small pool. The team also found evidence that, in mice, cathepsin B was causing the growth of new cells and connections in the hippocampus, an area of the brain that is central to memory. But the researchers needed to know whether the substance worked the same way in other species. So they tested monkeys, and found that exercise did, indeed, raise circulating levels of cathepsin in the blood. © 2016 npr

Keyword: Muscles; Learning & Memory
Link ID: 22353 - Posted: 06.24.2016

by Helen Thompson Young zebra finches (Taeniopygia guttata) learn to sing from a teacher, usually dad. Remembering dad’s tunes may even be hardwired into the birds’ brains. Researchers at the Okinawa Institute of Science and Technology in Japan measured activity in the brains of male juvenile birds listening to recordings of singing adult males, including their fathers. The team focused its efforts on neurons in a part of the brain called the caudomedial nidopallium that’s thought to influence song learning and memory. A subset of neurons in the caudomedial nidopallium lit up in response to songs performed by dad but not those of strangers, the team reports June 21 in Nature Communications. The more baby birds heard songs, the more their neurons responded and the clearer their own songs became. Sleep and a neurotransmitter called GABA influenced this selectivity. The researchers suggest that this particular region of the brain stores song memories as finches learn to sing, and GABA may drive the storage of dad’s songs over others. Researchers played a variety of sounds for young zebra finches: their own song, dad’s song and songs and calls from other adult finches. Over time, their songs became more and more similar to that of their father. |© Society for Science & the Public 2000 - 2016

Keyword: Animal Communication; Language
Link ID: 22351 - Posted: 06.23.2016

Laura Sanders If you want to lock new information into your brain, try working up a sweat four hours after first encountering it. This precisely timed trick, described June 16 in Current Biology, comes courtesy of 72 people who learned the location of 90 objects on a computer screen. Some of these people then watched relaxing nature videos, while others worked up a sweat on stationary bikes, alternating between hard and easy pedaling for 35 minutes. This workout came either soon after the cram session or four hours later. Compared with both the couch potatoes and the immediate exercisers, the people who worked out four hours after their learning session better remembered the objects’ locations two days later. The delayed exercisers also had more consistent activity in the brain’s hippocampus, an area important for memory, when they remembered correctly. That consistency indicates that the memories were stronger, Eelco van Dongen of the Donders Institute in the Netherlands and colleagues propose. The researchers don’t yet know how exercise works its memory magic, but they have a guess. Molecules sparked by aerobic exercise, including the neural messenger dopamine and the protein BDNF, may help solidify memories by reorganizing brain cell connections. Citations E. van Dongen et al. Physical exercise performed four hours after learning improves memory retention and increases hippocampal pattern similarity during retrieval. Current Biology. Published online June 16, 2016. doi: 10.1016/j.cub.2016.04.071. © Society for Science & the Public 2000 - 2016

Keyword: Learning & Memory
Link ID: 22330 - Posted: 06.18.2016

By Aleszu Bajak Can the various puzzles and quizzes associated with commercial brain-training games really improve cognitive function — or better yet, stave off cognitive decline? To date, the scientific evidence is murky, but that hasn’t kept companies from trying to cash-in on consumers’ native desire for quick fixes to complex health problems. The most famous among such companies is probably Lumosity, a product of San Francisco-based Lumos Labs, which once marketed its suite of web-based games and mobile apps as being “built on proven neuroscience,” and by encouraging users to “harness your brain’s neuroplasticity and train your way to a brighter life.” Exercising your brain with online brain-training games like Lumosity (above) or Smart Brain Aging sounds like a great idea, but the science is still murky. Exercising your brain with online brain-training games like Lumosity (above) or Smart Brain Aging sounds like a great idea, but the science is still murky. Those claims were among several that attracted the attention of the Federal Trade Commission, which earlier this year filed a complaint against the company. Lumosity was ultimately slapped with $50 million in fines for deceiving consumers — although $48 million of that was reportedly suspended by a district court, because the company was financially unable to pay the full amount. “Lumosity preyed on consumers’ fears about age-related cognitive decline, suggesting their games could stave off memory loss, dementia, and even Alzheimer’s disease,” said Jessica Rich, Director of the FTC’s Bureau of Consumer Protection, in a statement accompanying the settlement. “But Lumosity simply did not have the science to back up its ads.” Copyright 2016 Undark

Keyword: Alzheimers; Learning & Memory
Link ID: 22328 - Posted: 06.16.2016

By Ashley P. Taylor Sleep is known to aid memory and learning. For example, people who learn something, sleep on it, and are tested on the material after they wake up tend to perform better than those who remain awake in the interim. Within that general phenomenon, however, there’s a lot of unexplained variation. University of California, Riverside, sleep researcher Sara Mednick wondered “what else might be going during that sleep period that helps people’s memories,” she told The Scientist. As it turns out, activity of the autonomic nervous system (ANS) explains a large part of this variation, Mednick and colleagues show in a paper published today (June 13) in PNAS. The researchers measured not only the electrical activity of the brain during sleep, but also that of the heart, providing an indicator of ANS activity. They found that the beat-to-beat variation in heart rate accounted for much of the previously unexplained variation in how well people performed on memory and creativity tests following a nap. “There is a good possibility that this additional measure [heart-rate variability] may help account for discrepant findings in the sleep-dependent memory consolidation literature,” sleep and cognition researcher Rebecca Spencer of the University of Massachusetts, Amherst, who was not involved in the work, wrote in an email. “Perhaps we put too large of a focus on sleep physiology from the CNS [central nervous system] and ignore a significant role of the ANS.” © 1986-2016 The Scientist

Keyword: Sleep; Learning & Memory
Link ID: 22323 - Posted: 06.15.2016

By Julia Shaw Can you trust your memory? Picture this. You are in a room full of strangers and you are going around introducing yourself. You say your name to about a dozen people, and they say their names to you. How many of these names are you going to remember? More importantly, how many of these names are you going to misremember? Perhaps you call a person you just met John instead of Jack. This kind of thing happens all the time. Now magnify the situation. You are talking to a close friend, and you disclose something important to them, perhaps even something traumatic. You might, for example, say you witnessed the Paris attacks in 2015. But, how can you know for sure that your memory is accurate? Like most people, you probably feel that misremembering someone’s name is totally different from misremembering an important and emotional life event. That you could never forget #JeSuisParis, and will always have stable and reliable memories of such atrocities. I’m sure that is what those who witnessed 9/11, the 7/7 bombings in London or the assassination of JFK also thought. However, when experimenters conduct research on the accuracy of these so-called “flashbulb memories,” they find that many people make grave errors in their recollections of important historical and personal events. And these errors are more than just omissions. © 2016 Scientific American

Keyword: Learning & Memory
Link ID: 22320 - Posted: 06.14.2016

By Sandra G. Boodman Richard McGhee and his family believed the worst was behind them. McGhee, a retired case officer at the Defense Intelligence Agency who lives near Annapolis, had spent six months battling leukemia as part of a clinical trial at MD Anderson Cancer Center in Houston. The experimental chemotherapy regimen he was given had worked spectacularly, driving his blood cancer into a complete remission. But less than nine months after his treatment ended, McGhee abruptly fell apart. He became moody, confused and delusional — even childish — a jarring contrast with the even-keeled, highly competent person he had been. He developed tremors in his arms, had trouble walking and became incontinent. “I was really a mess,” he recalled. Doctors suspected he had developed a rapidly progressive and fatal dementia, possibly a particularly aggressive form of Alzheimer’s disease. If that was the case, his family was told, his life span would be measured in months. Luckily, the cause of McGhee’s precipitous decline proved to be much more treatable — and prosaic — than doctors initially feared. “It’s really a pleasure to see somebody get better so rapidly,” said Michael A. Williams, a professor of neurology and neurosurgery at the University of Washington School of Medicine in Seattle. Until recently, Williams was affiliated with Baltimore’s Sinai Hospital, where he treated McGhee in 2010. “This was a diagnosis waiting to be found.”

Keyword: Alzheimers; Neuroimmunology
Link ID: 22293 - Posted: 06.07.2016

By Clare Wilson We’ve all been there: after a tough mental slog your brain feels as knackered as your body does after a hard workout. Now we may have pinpointed one of the brain regions worn out by a mentally taxing day – and it seems to also affect our willpower, so perhaps we should avoid making important decisions when mentally fatigued. Several previous studies have suggested that our willpower is a finite resource, and if it gets depleted in one way – like finishing a difficult task – we find it harder to make other good choices, like resisting a slice of cake. In a small trial, Bastien Blain at INSERM in Paris and his colleagues asked volunteers to spend six hours doing tricky memory tasks, while periodically choosing either a small sum of cash now, or a larger amount after a delay. .. As the day progressed, people became more likely to act on impulse and to pick an immediate reward. This didn’t happen in the groups that spent time doing easier memory tasks, reading or gaming. For those engaged in difficult work, fMRI brain scans showed a decrease in activity in the middle frontal gyrus, a brain area involved in decision-making. “That suggests this region is becoming less excitable, which could be impairing people’s ability to resist temptation,” says Blain. It’s involved in decisions like ‘Shall I have a beer with my friends tonight, or shall I save money to buy a bike next month,’ he says. Previous research has shown that children with more willpower in a similar type of choice test involving marshmallows end up as more successful adults, by some measures. “Better impulse control predicts your eventual wealth and health,” says Blain. The idea that willpower can be depleted is contentious as some researchers have failed to replicate others’ findings. © Copyright Reed Business Information Ltd.

Keyword: Attention; Learning & Memory
Link ID: 22292 - Posted: 06.07.2016

By Julia Shaw A cure for almost every memory ailment seems to be just around the corner. Alzheimer’s affected brains can have their memories restored, we can create hippocampal implants to give us better memory, and we can effectively implant false memories with light. Except that we can’t really do any of these things, at least not in humans. We sometimes forget that developments in memory science need to go through a series of stages in order to come to fruition, each of which requires tremendous knowledge and skill. From coming up with a new idea, to designing an appropriate methodology, obtaining ethical approval, getting research funding, recruiting research assistants and test subjects, conducting the experiment(s), completing complex statistical analysis for which computer code is often required, writing a manuscript, surviving the peer review process, and finally effectively distributing the findings, each part of the process is incredibly complex and takes a long time. On top of it all, this process, which can take decades to complete, typically results in incremental rather than monumental change. Rather than creating massive leaps in technology, in the vast majority of instances, studies add a teeny tiny bit of insight to the greater body of knowledge. These incremental achievements in science are often blown out of proportion by the media. As John Oliver recently said “…[Science] deserves better than to be twisted out of proportion and be turned into morning show gossip.” Moving from science fiction to science fact is harder than the media makes it seem. © 2016 Scientific American,

Keyword: Learning & Memory; Robotics
Link ID: 22289 - Posted: 06.06.2016

By David Z. Hambrick If you’re a true dog lover, you take it as one of life’s simple truths that all dogs are good, and you have no patience for scientific debate over whether dogs really love people. Of course they do. What else could explain the fact that your dog runs wildly in circles when you get home from work, and, as your neighbors report, howls inconsolably for hours on end when you leave? What else could explain the fact that your dog insists on sleeping in your bed, under the covers—in between you and your partner? At the same time, there’s no denying that some dogs are smarter than others. Not all dogs can, like a border collie mix named Jumpy, do a back flip, ride a skateboard, and weave through pylons on his front legs. A study published in the journal Intelligence by British psychologists Rosalind Arden and Mark Adams confirms as much. Consistent with over a century of research on human intelligence, Arden and Adams found that a dog that excels in one test of cognitive ability will likely excel in other tests of cognitive ability. In more technical terms, the study reveals that there is a general factor of intelligence in dogs—a canine “g” factor. For their study, Arden and Adams devised a battery of canine cognitive ability tests. All of the tests revolved around—you guessed it—getting a treat. In the detour test, the dog’s objective was to navigate around barriers arranged in different configurations to get to a treat. In the point-following test, a researcher pointed to one of two inverted beakers concealing a treat, and recorded whether the dog went to that beaker or the other one. Finally, the quantity discrimination test required the dog to choose between a small treat (a glob of peanut butter) and a larger one (the “correct” answer). Arden and Adams administered the battery to 68 border collies from Wales; all had been bred and trained to do herding work on a farm, and thus had similar backgrounds. © 2016 Scientific American

Keyword: Intelligence; Evolution
Link ID: 22272 - Posted: 06.01.2016

By Gretchen Reynolds A weekly routine of yoga and meditation may strengthen thinking skills and help to stave off aging-related mental decline, according to a new study of older adults with early signs of memory problems. Most of us past the age of 40 are aware that our minds and, in particular, memories begin to sputter as the years pass. Familiar names and words no longer spring readily to mind, and car keys acquire the power to teleport into jacket pockets where we could not possibly have left them. Some weakening in mental function appears to be inevitable as we age. But emerging science suggests that we might be able to slow and mitigate the decline by how we live and, in particular, whether and how we move our bodies. Past studies have found that people who run, weight train, dance, practice tai chi, or regularly garden have a lower risk of developing dementia than people who are not physically active at all. There also is growing evidence that combining physical activity with meditation might intensify the benefits of both pursuits. In an interesting study that I wrote about recently, for example, people with depression who meditated before they went for a run showed greater improvements in their mood than people who did either of those activities alone. But many people do not have the physical capacity or taste for running or other similarly vigorous activities. So for the new study, which was published in April in the Journal of Alzheimer’s Disease, researchers at the University of California, Los Angeles, and other institutions decided to test whether yoga, a relatively mild, meditative activity, could alter people’s brains and fortify their ability to think. © 2016 The New York Times Company

Keyword: Learning & Memory
Link ID: 22270 - Posted: 06.01.2016

Robert Plomin, Scientists have investigated this question for more than a century, and the answer is clear: the differences between people on intelligence tests are substantially the result of genetic differences. But let's unpack that sentence. We are talking about average differences among people and not about individuals. Any one person's intelligence might be blown off course from its genetic potential by, for example, an illness in childhood. By genetic, we mean differences passed from one generation to the next via DNA. But we all share 99.5 percent of our three billion DNA base pairs, so only 15 million DNA differences separate us genetically. And we should note that intelligence tests include diverse examinations of cognitive ability and skills learned in school. Intelligence, more appropriately called general cognitive ability, reflects someone's performance across a broad range of varying tests. Genes make a substantial difference, but they are not the whole story. They account for about half of all differences in intelligence among people, so half is not caused by genetic differences, which provides strong support for the importance of environmental factors. This estimate of 50 percent reflects the results of twin, adoption and DNA studies. From them, we know, for example, that later in life, children adopted away from their biological parents at birth are just as similar to their biological parents as are children reared by their biological parents. Similarly, we know that adoptive parents and their adopted children do not typically resemble one another in intelligence. © 2016 Scientific American

Keyword: Intelligence; Genes & Behavior
Link ID: 22264 - Posted: 05.31.2016

By BENEDICT CAREY Suzanne Corkin, whose painstaking work with a famous amnesiac known as H.M. helped clarify the biology of memory and its disorders, died on Tuesday in Danvers, Mass. She was 79. Her daughter, Jocelyn Corkin, said the cause was liver cancer. Dr. Corkin met the man who would become a lifelong subject and collaborator in 1964, when she was a graduate student in Montreal at the McGill University laboratory of the neuroscientist Brenda Milner. Henry Molaison — known in published reports as H.M., to protect his privacy — was a modest, middle-aged former motor repairman who had lost the ability to form new memories after having two slivers of his brain removed to treat severe seizures when he was 27. In a series of experiments, Dr. Milner had shown that a part of the brain called the hippocampus was critical to the consolidation of long-term memories. Most scientists had previously thought that memory was not dependent on any one cortical area. Mr. Molaison lived in Hartford, and Dr. Milner had to take the train down to Boston and drive from there to Connecticut to see him. It was a long trip, and transporting him to Montreal proved to be so complicated, largely because of his condition, that Dr. Milner did it just once. Yet rigorous study of H.M., she knew, would require proximity and a devoted facility — with hospital beds — to accommodate extended experiments. The psychology department at the Massachusetts Institute of Technology offered both, and with her mentor’s help, Dr. Corkin landed a position there. Thus began a decades-long collaboration between Dr. Corkin and Mr. Molaison that would extend the work of Dr. Milner, focus intense interest on the hippocampus, and make H.M. the most famous patient in the history of modern brain science. © 2016 The New York Times Company

Keyword: Learning & Memory
Link ID: 22258 - Posted: 05.28.2016

Laura Sanders In mice, a long course of antibiotics that wiped out gut bacteria slowed the birth of new brain cells and impaired memory, scientists write May 19 in Cell Reports. The results reinforce evidence for a powerful connection between bacteria in the gut and the brain (SN: 4/2/16, p. 23). After seven weeks of drinking water spiked with a cocktail of antibiotics, mice had fewer newborn nerve cells in a part of the hippocampus, a brain structure important for memory. The mice’s ability to remember previously seen objects also suffered. Further experiments revealed one way bacteria can influence brain cell growth and memory. Injections of immune cells called Ly6Chi monocytes boosted the number of new nerve cells. Themonocytes appear to carry messages from gut to brain, Susanne Wolf of the Max Delbrück Center for Molecular Medicine in Berlin and colleagues found. Exercise and probiotic treatment with eight types of live bacteria also increased the number of newborn nerve cells and improved memory in mice treated with antibiotics. The results help clarify the toll of prolonged antibiotic treatment, and hint at ways to fight back, the authors write. L. Möhle et al. Ly6Chi monocytes provide a link between antibiotic-induced changes in gut microbiota and adult hippocampal neurogenesis. Cell Reports. Vol. 15, May 31, 2016. doi: 10.1016/j.celrep.2016.04.074. © Society for Science & the Public 2000 - 2016

Keyword: Obesity; Learning & Memory
Link ID: 22231 - Posted: 05.21.2016

By JONATHAN BALCOMBE Washington — IN March, two marine biologists published a study of giant manta rays responding to their reflections in a large mirror installed in their aquarium in the Bahamas. The two captive rays circled in front of the mirror, blew bubbles and performed unusual body movements as if checking their reflection. They made no obvious attempt to interact socially with their reflections, suggesting that they did not mistake what they saw as other rays. The scientists concluded that the mantas seemed to be recognizing their reflections as themselves. Mirror self-recognition is a big deal. It indicates self-awareness, a mental attribute previously known only among creatures of noted intelligence like great apes, dolphins, elephants and magpies. We don’t usually think of fishes as smart, let alone self-aware. As a biologist who specializes in animal behavior and emotions, I’ve spent the past four years exploring the science on the inner lives of fishes. What I’ve uncovered indicates that we grossly underestimate these fabulously diverse marine vertebrates. The accumulating evidence leads to an inescapable conclusion: Fishes think and feel. Because fishes inhabit vast, obscure habitats, science has only begun to explore below the surface of their private lives. They are not instinct-driven or machinelike. Their minds respond flexibly to different situations. They are not just things; they are sentient beings with lives that matter to them. A fish has a biography, not just a biology. Those giant manta rays have the largest brains of any fish, and their relative brain-to-body size is comparable to that of some mammals. So, an exception? Then you haven’t met the frillfin goby. © 2016 The New York Times Company

Keyword: Intelligence; Evolution
Link ID: 22221 - Posted: 05.16.2016

By Julia Shaw You see a crime take place. You are interviewed about it. You give a statement about what you saw. Do you think that at a later date you would be able to detect whether someone had tampered with your statement? Or re-written parts of it? This is currently a hot topic in the UK, where a very recently published inquiry into the so-called Hillsborough disaster, in which 96 people were crushed to death during a soccer match in 1989, found that testimonies had been deliberately altered by police. Research published earlier this year by the false memory dream team at the University of California, looked directly into the implications of such police (mis)conduct. They found that it is possible that changed statements can go unnoticed by the person who gave the original testimony, and may even develop into a false memory that accommodates the false account. To describe this effect, the researchers came up with the term "memory blindness"—the phenomenon of failing to recognize our own memories. The term was intended to mirror the ‘choice blindness’ literature. Choice blindness is forgetting choices that we have made. The researchers wanted to know “Can choice blindness have lasting effects on eyewitness memory?” To examine this, PhD Student Kevin Cochran and his colleagues conducted two experiments. © 2016 Scientific American

Keyword: Learning & Memory
Link ID: 22218 - Posted: 05.16.2016

Bret Stetka Last year, in an operating room at the University of Toronto, a 63-year-old women with Alzheimer's disease experienced something she hadn't for 55 years: a memory of her 8-year-old self playing with her siblings on their family farm in Scotland. The woman is a patient of Dr. Andres Lozano, a neurosurgeon who is among a growing number of researchers studying the potential of deep brain stimulation to treat Alzheimer's and other forms of dementia. If the approach pans out it could provide options for patients with fading cognition and retrieve vanished memories. Right now, deep brain stimulation is used primarily to treat Parkinson's disease and tremor, for which it's approve by the Food and Drug Administration. DBS involves delivering electrical impulses to specific areas of the brain through implanted electrodes. The technique is also approved for obsessive-compulsive disorder and is being looked at for a number of other brain disorders, including depression, chronic pain and, as in Lozano's work, dementia. In 2008 Lozano's group published a study in which an obese patient was treated with deep brain stimulation of the hypothalamus. Though no bigger than a pea, the hypothalamus is a crucial bit of brain involved in appetite regulation and other bodily essentials such as temperature control, sleep and circadian rhythms. It seemed like a reasonable target in trying to suppress excessive hunger. To the researcher's surprise, following stimulation the patient reported a sensation of deja vu. He also perceived feeling 20 years younger and recalled a memory of being in a park with friends, including an old girlfriend. With increasing voltages his memories became more vivid. He remembered their clothes. © 2016 npr

Keyword: Learning & Memory
Link ID: 22213 - Posted: 05.14.2016

Laura Sanders Brain waves during REM sleep solidify memories in mice, scientists report in the May 13 Science. Scientists suspected that the eye-twitchy, dream-packed slumber known as rapid eye movement sleep was important for memory. But REM sleep’s influence on memory has been hard to study, in part because scientists often resorted to waking people or animals up — a stressful experience that might influence memory in different ways. Richard Boyce of McGill University in Montreal and colleagues interrupted REM sleep in mice in a more delicate way. Using a technique called optogenetics, the researchers blocked a brain oscillation called theta waves in the hippocampus, a brain structure involved in memory, during REM sleep. This light touch meant that the mice stayed asleep but had fewer REM-related theta waves in their hippocampi. Usually, post-learning sleep helps strengthen memories. But mice with disturbed REM sleep had memory trouble, the researchers found. Curious mice will spend more time checking out an object that’s been moved to a new spot than an unmoved object. But after the sleep treatment, the mice seemed to not remember objects’ earlier positions, spending equal time exploring an unmoved object as one in a new place. These mice also showed fewer signs of fear in a place where they had previously suffered shocks. Interfering with theta waves during other stages of sleep didn’t seem to cause memory trouble, suggesting that something special happens during REM sleep. R. Boyce et al. Causal evidence for the role of REM sleep theta rhythm in contextual memory consolidation. Science. Vol. 352, p. 812, May 13, 2016. doi: 10.1126/science.aad5252. © Society for Science & the Public 2000 - 2016.

Keyword: Sleep; Learning & Memory
Link ID: 22211 - Posted: 05.14.2016

Erika Check Hayden The largest-ever genetics study in the social sciences has turned up dozens of DNA markers that are linked to the number of years of formal education an individual completes. The work, reported this week in Nature, analysed genetic material from around 300,000 people. “This is good news,” says Stephen Hsu, a theoretical physicist at Michigan State University in East Lansing, who studies the genetics of intelligence. “It shows that if you have enough statistical power you can find genetic variants that are associated with cognitive ability.” Yet the study’s authors estimate that the 74 genetic markers they uncovered comprise just 0.43% of the total genetic contribution to educational achievement (A. Okbay et al. Nature http://dx.doi.org/10.1038/nature17671; 2016). By themselves, the markers cannot predict a person’s performance at school. And because the work examined only people of European ancestry, it is unclear whether the results apply to those with roots in other regions, such as Africa or Asia. The findings have proved divisive. Some researchers hope that the work will aid studies of biology, medicine and social policy, but others say that the emphasis on genetics obscures factors that have a much larger impact on individual attainment, such as health, parenting and quality of schooling. © 2016 Nature Publishing Group

Keyword: Genes & Behavior; Learning & Memory
Link ID: 22209 - Posted: 05.12.2016

By Hazem Zohny Here is a picture of the nine-dot problem. The task seems simple enough: connect all nine dots with four straight lines, but, do so without lifting the pen from the paper or retracing any line. If you don’t already know the solution, give it a try – although your chances of figuring it out within a few minutes hover around 0 percent. In fact, even if I were to give you a hint like “think outside of the box,” you are unlikely to crack this deceptively (and annoyingly!) simple puzzle. And yet, if we were to pass a weak electric current through your brain (specifically your anterior temporal lobe, which sits somewhere between the top of your ear and temple), your chances of solving it may increase substantially. That, at least, was the finding from a study where 40 percent of people who couldn’t initially solve this problem managed to crack it after 10 minutes of transcranial direct current stimulation (tDCS) – a technique for delivering a painlessly weak electric current to the brain through electrodes on the scalp. How to explain this? It is an instance of the alleged power of tDCS and similar neurostimulation techniques. These are increasingly touted as methods that can “overclock” the brain in order to boost cognition, improve our moods, make us stronger, and even alter our moral dispositions. The claims are not completely unfounded: there is evidence that some people become slightly better at holding and manipulating information in their minds after a bout of tDCS. It also appears to reduce some people’s likelihood of formulating false memories, and seems to have a lasting improvement on some people’s ability to work with numbers. It can even appear to boost creativity, enhancing the ability of some to make abstract connections between words to come up with creative analogies. But it goes further, with some evidence that it can help people control their urges as well improve their mood. And beyond these psychological effects, tDCS of the part of the brain responsible for movement seems to improve muscular endurance and reduce fatigue. © 2016 Scientific American

Keyword: Learning & Memory
Link ID: 22205 - Posted: 05.11.2016