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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

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 5: The Sensorimotor System
Link ID: 22704 - Posted: 09.28.2016

Ramin Skibba. Physiologist Ivan Pavlov conditioned dogs to associate food with the sound of a buzzer, which left them salivating. Decades later, researchers discovered such training appears to block efforts to teach the animals to link other stimuli to the same reward. Dogs trained to expect food when a buzzer sounds can then be conditioned to salivate when they are exposed to the noise and a flash of light simultaneously. But light alone will not cue them to drool. This ‘blocking effect’ is well-known in psychology, but new research suggests that the concept might not be so simple. Psychologists in Belgium failed to replicate the effect in 15 independent experiments, they report this month in the Journal of Experimental Psychology1. “For a long time, you tend to think, ‘It’s me’ — I’m doing something wrong, or messing up the experiment,’” says lead author Tom Beckers, a psychologist at the Catholic University of Leuven (KU Leuven) in Belgium. But after his student, co-author Elisa Maes, also could not replicate the blocking effect, and the team failed again in experiments in other labs, Beckers realized that “it can’t just be us”. The scientists do not claim that the blocking effect is not real, or that previous observations of it are wrong. Instead, Beckers thinks that psychologists do not yet know enough about the precise conditions under which it applies. © 2016 Macmillan Publishers Limited,

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22701 - Posted: 09.27.2016

By Julia Shaw The brain, with its 100 billion neurons, allows us to do amazing things like learn multiple languages, or build things that send people into outer space. Yet despite this astonishing capacity, we routinely can’t remember where we put our keys, we forget why we went to the grocery store, and we fail when trying to recall personal life events. This apparent contradiction in functionality opens up the question of why we forget some things but remember others. Or, more fundamentally, what causes forgetting? This week my book ‘The Memory Illusion’ drops in Canada, and as a Canadian girl I want to celebrate this by showcasing some Canadian researchers who have given us insight into precisely this question. An article published recently in Psychological Science by Talya Sadeh and colleagues at the Rotman Research institute in Toronto addresses a long-running debate in the world of memory science; do we forget things because of decay or interference? Decay. Advocates of the decay account posit that our memories slowly disappear, fading because of a passage of time during which they have not been accessed. You can picture this much like a message written in sand, with every ocean wave that flows over the shore making the writing less legible until it eventually disappears entirely. The sand represents the web of brain cells that form a memory in the brain, and the ocean waves represent time passing. © 2016 Scientific American,

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22651 - Posted: 09.13.2016

By Karen Zusi At least one type of social learning, or the ability to learn from observing others’ actions, is processed by individual neurons within a region of the human brain called the rostral anterior cingulate cortex (rACC), according to a study published today (September 6) in Nature Communications. The work is the first direct analysis in humans of the neuronal activity that encodes information about others’ behavior. “The idea [is] that there could be an area that’s specialized for processing things about other people,” says Matthew Apps, a neuroscientist at the University of Oxford who was not involved with the study. “How we think about other people might use distinct processes from how we might think about ourselves.” During the social learning experiments, the University of California, Los Angeles (UCLA) and CalTech–based research team recorded the activity of individual neurons in the brains of epilepsy patients. The patients were undergoing a weeks-long procedure at the Ronald Reagan UCLA Medical Center in which their brains were implanted with electrodes to locate the origin of their epileptic seizures. Access to this patient population was key to the study. “It’s a very rare dataset,” says Apps. “It really does add a lot to the story.” With data streaming out of the patients’ brains, the researchers taught the subjects to play a card game on a laptop. Each turn, the patients could select from one of two decks of face-down cards: the cards either gave $10 or $100 in virtual winnings, or subtracted $10 or $100. In one deck, 70 percent of the cards were winning cards, while in the other only 30 percent were. The goal was to rack up the most money. © 1986-2016 The Scientist

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 14: Attention and Consciousness
Link ID: 22640 - Posted: 09.10.2016

By Amy Ellis Nutt Before iPhones and thumb drives, before Google docs and gigabytes of RAM, memory was more art than artifact. It wasn’t a tool or a byproduct of being human. It was essential to our character and therefore a powerful theme in both myth and literature. At the end of Book 2 of the “Divine Comedy,” with Paradise nearly in reach, Dante is dipped into the River Lethe, where the sins of the self are washed away in the waters of forgetfulness. To be truly cleansed of his memories, however, Dante must also drink from the river of oblivion. Only then will he be truly purified and the memories of his good deeds restored to him. Before we can truly remember, according to Dante, we must forget. In “Patient H.M.: A Story of Memory, Madness, and Family Secrets,” author Luke Dittrich seems to be saying that before we can forgive, we must remember. The terrible irony is that H.M., the real-life character around whom Dittrich’s book revolves, had no memory at all. In prose both elegant and intimate, and often thrilling, “Patient H.M.” is an important book about the wages not of sin but of science. It is deeply reported and surprisingly emotional, at times poignant, at others shocking. H.M., arguably the single most important research subject in the history of neuroscience, was once Henry Molaison, an ordinary New England boy. When Henry was 9 years old, he was hit by a bicyclist as he walked across the street in his home town, Hartford, Conn. © 1996-2016 The Washington Post

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22604 - Posted: 08.27.2016

By Anna Azvolinsky Sets of neurons in the brain that behave together—firing synchronously in response to sensory or motor stimuli—are thought to be functionally and physiologically connected. These naturally occurring ensembles of neurons are one of the ways memories may be programmed in the brain. Now, in a paper published today (August 11) in Science, researchers at Columbia University and their colleagues show that it is possible to stimulate visual cortex neurons in living, awake mice and induce a new ensemble of neurons that behave as a group and maintain their concerted firing for several days. “This work takes the concept of correlated [neuronal] firing patterns in a new and important causal direction,” David Kleinfeld, a neurophysicist at the University of California, San Diego, who was not involved in the work told The Scientist. “In a sense, [the researchers] created a memory for a visual feature that does not exist in the physical world as a proof of principal of how real visual memories are formed.” “Researchers have previously related optogenetic stimulation to behavior [in animals], but this study breaks new ground by investigating the dynamics of neural activity in relation to the ensemble to which these neurons belong,” said Sebastian Seung, a computational neuroscientist at the Princeton Neuroscience Institute in New Jersey who also was not involved in the study. Columbia’s Rafael Yuste and colleagues stimulated randomly selected sets of individual neurons in the visual cortices of living mice using two-photon stimulation while the animals ran on a treadmill. © 1986-2016 The Scientist

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 13: Memory, Learning, and Development
Link ID: 22558 - Posted: 08.13.2016

Ed Yong At the age of seven, Henry Gustav Molaison was involved in an accident that left him with severe epilepsy. Twenty years later, a surgeon named William Scoville tried to cure him by removing parts of his brain. It worked, but the procedure left Molaison unable to make new long-term memories. Everyone he met, every conversation he had, everything that happened to him would just evaporate from his mind. These problems revolutionized our understanding of how memory works, and transformed Molaison into “Patient H.M.”—arguably the most famous and studied patient in the history of neuroscience. That’s the familiar version of the story, but the one presented in Luke Dittrich’s new book Patient H.M.: A Story of Memory, Madness, and Family Secrets is deeper and darker. As revealed through Dittrich’s extensive reporting and poetic prose, Molaison’s tale is one of ethical dilemmas that not only influenced his famous surgery but persisted well beyond his death in 2008. It’s a story about more than just the life of one man or the root of memory; it’s also about how far people are willing to go for scientific advancement, and the human cost of that progress. And Dittrich is uniquely placed to consider these issues. Scoville was his grandfather. Suzanne Corkin, the scientist who worked with Molaison most extensively after his surgery, was an old friend of his mother’s. I spoke to him about the book and the challenges of reporting a story that he was so deeply entwined in. Most of this interview was conducted on July 19th. Following a New York Times excerpt published on August 7th, and the book’s release two weeks later, many neuroscientists have expressed “outrage” at Dittrich’s portrayal of Corkin. The controversy culminated in a statement from MIT, where Corkin was based, rebutting three allegations in the book. Dittrich has himself responded to the rebuttals, and at the end of this interview, I talk to him about the debate. © 2016 by The Atlantic Monthly Group.

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22552 - Posted: 08.13.2016

Like many students of neuroscience, I first learned of patient HM in a college lecture. His case was so strange yet so illuminating, and I was immediately transfixed. HM was unable to form new memories, my professor explained, because a surgeon had removed a specific part of his brain. The surgery froze him in time. HM—or Henry Molaison, as his name was revealed to be after his death in 2008—might be the most famous patient in the history of brain research. He is now the subject of the new book, Patient HM: A Story of Memory, Madness, and Family Secrets. An excerpt from the book in the New York Times Magazine, which details MIT neuroscientist Sue Corkin’s custody fight over HM’s brain after his death, has since sparked a backlash. Should you wish to go down that particular rabbit hole, you can read MIT’s response, the book author’s response to the response, and summaries of the back and forth. Why HM’s brain was worth fighting over should be obvious; he was probably the most studied individual in neuroscience while alive. But in the seven years since scientists sectioned HM’s brain into 2,401 slices, it has yielded surprisingly little research. Only two papers examining his brain have come out, and so far, physical examinations have led to no major insights. HM’s scientific potential remains unfulfilled—thanks to delays from the custody fight and the limitations of current neuroscience itself. Corkin, who made her career studying HM, confronted her complicated emotions about his death in her own 2013 book. She describes being “ecstatic to see his brain removed expertly from his skull.” Corkin passed away earlier this year.

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22551 - Posted: 08.13.2016

By Sharon Begley, The Massachusetts Institute of Technology brain sciences department and, separately, a group of some 200 neuroscientists from around the world have written letters to The New York Times claiming that a book excerpt in the newspaper’s Sunday magazine this week contains important errors, misinterpretations of scientific disputes, and unfair characterizations of an MIT neuroscientist who did groundbreaking research on human memory. In particular, the excerpt contains a 36-volley verbatim exchange between author Luke Dittrich and MIT’s Suzanne Corkin in which she says that key documents from historic experiments were “shredded.” “Most of it has gone, is in the trash, was shredded,” Corkin is quoted as telling Dittrich before she died in May, explaining, “there’s no place to preserve it.” Destroying files related to historic scientific research would raise eyebrows, but Corkin’s colleagues say it never happened. “We believe that no records were destroyed and, to the contrary, that professor Corkin worked in her final days to organize and preserve all records,” said the letter that Dr. James DiCarlo, head of the MIT Department of Brain and Cognitive Sciences, sent to the Times late Tuesday. Even as Corkin fought advanced liver cancer, he wrote, “she instructed her assistant to continue to organize, label, and maintain all records” related to the research, and “the records currently remain within our department.” © 2016 Scientific American

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22546 - Posted: 08.11.2016

BENEDICT CAREY As a boy growing up in Massachusetts, Luke Dittrich revered his grandfather, a brain surgeon whose home was full of exotic instruments. Later, he learned that he was not only a prominent doctor but had played a significant role in modern medical history. In 1953, at Hartford Hospital, Dr. William Scoville had removed two slivers of tissue from the brain of a 27-year-old man with severe epilepsy. The operation relieved his seizures but left the patient — Henry Molaison, a motor repairman — unable to form new memories. Known as H. M. to protect his privacy, Mr. Molaison went on to become the most famous patient in the history of neuroscience, participating in hundreds of experiments that have helped researchers understand how the brain registers and stores new experiences. By the time Mr. Dittrich was out of college — and after a year and a half in Egypt, teaching English — he had become fascinated with H. M., brain science and his grandfather’s work. He set out to write a book about the famous case but discovered something unexpected along the way. His grandfather was one of a cadre of top surgeons who had performed lobotomies and other “psycho-surgeries” on thousands of people with mental problems. This was not a story about a single operation that went wrong; it was far larger. The resulting book — “Patient H. M.: A Story of Memory, Madness, and Family Secrets,” to be published Tuesday — describes a dark era of American medicine through a historical, and deeply personal, lens. Why should scientists and the public know this particular story in more detail? The textbook story of Patient H. M. — the story I grew up with — presents the operation my grandfather performed on Henry as a sort of one-off mistake. It was not. Instead, it was the culmination of a long period of human experimentation that my grandfather and other leading doctors and researchers had been conducting in hospitals and asylums around the country. © 2016 The New York Times Company

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22531 - Posted: 08.09.2016

By Julia Shaw Every memory you have ever had is chock-full of errors. I would even go as far as saying that memory is largely an illusion. This is because our perception of the world is deeply imperfect, our brains only bother to remember a tiny piece of what we actually experience, and every time we remember something we have the potential to change the memory we are accessing. I often write about the ways in which our memory leads us astray, with a particular focus on ‘false memories.’ False memories are recollections that feel real but are not based on actual experience. For this particular article I invited a few top memory researchers to comment on what they wish everyone knew about their field. First up, we have Elizabeth Loftus from the University of California, Irvine, who is one of the founders of the area of false memory research, and is considered one of the most ‘eminent psychologists of the 20th century.’ Elizabeth Loftus says you need independent evidence to corroborate your memories. According to Loftus: “The one take home message that I have tried to convey in my writings, and classes, and in my TED talk is this: Just because someone tells you something with a lot of confidence and detail and emotion, it doesn't mean it actually happened. You need independent corroboration to know whether you're dealing with an authentic memory, or something that is a product of some other process.” Next up, we have memory scientist Annelies Vredeveldt from the Vrije Universiteit Amsterdam, who has done fascinating work on how well we remember when we recall things with other people. © 2016 Scientific American,

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22530 - Posted: 08.09.2016

Pete Etchells Mind gamers: How good do you reckon your memory is? We might forget things from time to time, but the stuff we do remember is pretty accurate, right? The trouble is, our memory isn’t as infallible as we might want to believe, and you can test this for yourself using the simple experiment below. All done? Great. Now we’re going to do a simple recognition test – below is another list of words for you to look at. Without looking back, note down which of them appeared in the three lists you just scanned. No cheating! If you said that top, seat and yawn were in the lists, you’re spot on. Likewise, if you think that slow, sweet and strong didn’t appear anywhere, you’re also right. What about chair, mountain and sleep though? They sound like they should have been in the lists, but they never made an appearance. Some of you may have spotted this, but a lot of people tend to say, with a fair amount of certainty, that the words were present. This experiment comes from a classic 1995 study by Henry L. Roediger and Kathleen McDermott at Rice University in Texas. Based on earlier work by James Deese (hence the name Deese-Roediger-McDermott, or DRM, paradigm), participants heard a series of word lists, which they then had to recall from memory. After a brief conversation with the researcher, the participants were then given a new list of words. Critically, this new list contained some words that were associated with every single item on each of the initial lists – for example, while sleep doesn’t appear on list 3 above, it’s related to each word that does appear (bed, rest, tired, and so on). © 2016 Guardian News and Media Limited

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22526 - Posted: 08.08.2016

By LUKE DITTRICH ‘Can you tell me who the president of the United States is at the moment?” A man and a woman sat in an office in the Clinical Research Center at the Massachusetts Institute of Technology. It was 1986, and the man, Henry Molaison, was about to turn 60. He was wearing sweatpants and a checkered shirt and had thick glasses and thick hair. He pondered the question for a moment. “No,” he said. “I can’t.” The woman, Jenni Ogden, was a visiting postdoctoral research fellow from the University of Auckland, in New Zealand. One of the greatest thrills of her time at M.I.T. was the chance to have sit-down sessions with Henry. In her field — neuropsychology — he was a legendary figure, something between a rock star and a saint. “Who’s the last president you remember?” “I don’t. ... ” He paused for a second, mulling over the question. He had a soft, tentative voice, a warm New England accent. “Ike,” he said finally. Dwight D. Eisenhower’s inauguration took place in 1953. Our world had spun around the sun more than 30 times since, though Henry’s world had stayed still, frozen in orbit. This is because 1953 was the year he received an experimental operation, one that destroyed most of several deep-­seated structures in his brain, including his hippocampus, his amygdala and his entorhinal cortex. The operation, performed on both sides of his brain and intended to treat Henry’s epilepsy, rendered him profoundly amnesiac, unable to hold on to the present moment for more than 30 seconds or so. That outcome, devastating to Henry, was a boon to science: By 1986, Patient H.M. — as he was called in countless journal articles and textbooks — had become arguably the most important human research subject of all time, revolutionizing our understanding of how memory works. © 2016 The New York Times Company

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22519 - Posted: 08.04.2016

Meghan Rosen Exercise may not erase old memories, as some studies in animals have previously suggested. Running on an exercise wheel doesn’t make rats forgetprevious trips through an underwater maze, Ashok Shetty and colleagues report August 2 in the Journal of Neuroscience. Exercise or not, four weeks after learning how to find a hidden platform, rats seem to remember the location just fine, the team found. The results conflict with two earlier papers that show that running triggers memory loss in some rodents by boosting the birth of new brain cells. Making new brain cells rejiggers memory circuits, and that can make it hard for animals to remember what they’ve learned, says Paul Frankland, a neuroscientist at the Hospital for Sick Children in Toronto. He has reported this phenomenon in mice, guinea pigs and degus (SN: 6/14/14, p. 7). Maybe rats are the exception, he says, “but I’m not convinced.” In 2014, Frankland and colleagues reported that brain cell genesis clears out fearful memories in three different kinds of rodents. Two years later, Frankland’s team found similar results with spatial memories. After exercising, mice had trouble remembering the location of a hidden platform in a water maze, the team reported in February in Nature Communications. Again, Frankland and colleagues pinned the memory wipeout on brain cell creation — like a chalkboard eraser that brushes away old information. The wipe seemed to clear the way for new memories to form. Shetty, a neuroscientist at Texas A&M Health Science Center in Temple, wondered if the results held true in rats, too. “Rats are quite different from mice,” he says. “Their biology is similar to humans.” |© Society for Science & the Public 2000 - 2016. All rights reserved.

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 5: The Sensorimotor System
Link ID: 22510 - Posted: 08.03.2016

By Bahar Gholipour After reflexively reaching out to grab a hot pan falling from the stove, you may be able to withdraw your hand at the very last moment to avoid getting burned. That is because the brain's executive control can step in to break a chain of automatic commands. Several new lines of evidence suggest that the same may be true when it comes to the reflex of recollection—and that the brain can halt the spontaneous retrieval of potentially painful memories. Within the brain, memories sit in a web of interconnected information. As a result, one memory can trigger another, making it bubble up to the surface without any conscious effort. “When you get a reminder, the mind's automatic response is to do you a favor by trying to deliver the thing that's associated with it,” says Michael Anderson, a neuroscientist at the University of Cambridge. “But sometimes we are reminded of things we would rather not think about.” Humans are not helpless against this process, however. Previous imaging studies suggest that the brain's frontal areas can dampen the activity of the hippocampus, a crucial structure for memory, and therefore suppress retrieval. In an effort to learn more, Anderson and his colleagues recently investigated what happens after the hippocampus is suppressed. They asked 381 college students to learn pairs of loosely related words. Later, the students were shown one word and asked to recall the other—or to do the opposite and to actively not think about the other word. Sometimes between these tasks they were shown unusual images, such as a peacock standing in a parking lot. © 2016 Scientific American

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22500 - Posted: 08.01.2016

By Gretchen Reynolds Learning requires more than the acquisition of unfamiliar knowledge; that new information or know-how, if it’s to be more than ephemeral, must be consolidated and securely stored in long-term memory. Mental repetition is one way to do that, of course. But mounting scientific evidence suggests that what we do physically also plays an important role in this process. Sleep, for instance, reinforces memory. And recent experiments show that when mice and rats jog on running wheels after acquiring a new skill, they learn much better than sedentary rodents do. Exercise seems to increase the production of biochemicals in the body and brain related to mental function. Researchers at the Donders Institute for Brain, Cognition and Behavior at Radboud University in the Netherlands and the University of Edinburgh have begun to explore this connection. For a study published this month in Current Biology, 72 healthy adult men and women spent about 40 minutes undergoing a standard test of visual and spatial learning. They observed pictures on a computer screen and then were asked to remember their locations. Afterward, the subjects all watched nature documentaries. Two-thirds of them also exercised: Half were first put through interval training on exercise bicycles for 35 minutes immediately after completing the test; the others did the same workout four hours after the test. Two days later, everyone returned to the lab and repeated the original computerized test while an M.R.I. machine scanned their brain activity. Those who exercised four hours after the test recognized and recreated the picture locations most accurately. Their brain activity was subtly different, too, showing a more consistent pattern of neural activity. The study’s authors suggest that their brains might have been functioning more efficiently because they had learned the patterns so fully. But why delaying exercise for four hours was more effective than an immediate workout remains mysterious. By contrast, rodents do better in many experiments if they work out right after learning. © 2016 The New York Times Company

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 5: The Sensorimotor System
Link ID: 22486 - Posted: 07.28.2016

By Tanya Lewis Scientists have made significant progress toward understanding how individual memories are formed, but less is known about how multiple memories interact. Researchers from the Hospital for Sick Children in Toronto and colleagues studied how memories are encoded in the amygdalas of mice. Memories formed within six hours of each other activate the same population of neurons, whereas distinct sets of brain cells encode memories formed farther apart, in a process whereby neurons compete with their neighbors, according to the team’s study, published today (July 21) in Science. “Some memories naturally go together,” study coauthor Sheena Josselyn of the Hospital for Sick Children told The Scientist. For example, you may remember walking down the aisle at your wedding ceremony and, later, your friend having a bit too much to drink at the reception. “We’re wondering about how these memories become linked in your mind,” Josselyn said. When the brain forms a memory, a group of neurons called an “engram” stores that information. Neurons in the lateral amygdala—a brain region involved in memory of fearful events—are thought to compete with one another to form an engram. Cells that are more excitable or have higher expression of the transcription factor CREB—which is critical for the formation of long-term memories—at the time the memory is being formed will “win” this competition and become part of a memory. © 1986-2016 The Scientist

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22467 - Posted: 07.23.2016

By TRIP GABRIEL DO you remember June 27, 2015? If you knew you had been on a sailboat, and that the weather was miserable, and that afterward you had a beer with the other sailors, would you expect to recall — even one year later — at least a few details? I was on that boat, on a blustery Saturday on Long Island Sound. But every detail is missing from my memory, as if snipped out by an overzealous movie editor. The earliest moment I recall from the day is lying in an industrial tube with a kind of upturned colander over my face, fighting waves of claustrophobia. My mind was densely fogged, but I understood that I was in an M.R.I. machine. Someone was scanning my brain. Other hazy scenes followed: being wheeled into a hospital room. My wife, Alice, hovering in the background. A wall clock that read minutes to midnight, an astonishing piece of information. What had happened to the day? Late that night, alone in the room, I noticed two yellow Post-its on the bedside table in Alice’s writing: “You have a condition called transient global amnesia. It will last Hours not DAYS. You’re going to be fine. Your CT scan was clear. You sailed today and drove yourself home,” the note read in part. I had never heard of transient global amnesia, a rare condition in which you are suddenly unable to recall recent events. Its causes are unknown. Unlike other triggers of memory loss, like a stroke or epileptic seizures, the condition is considered harmless, and an episode does not last long. “We don’t understand why it happens,” a neurologist would later tell me. “There are a million theories.” © 2016 The New York Times Company

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22456 - Posted: 07.19.2016

By Andy Coghlan There once was a brainy duckling. It could remember whether shapes or colours it saw just after hatching were the same as or different to each other. The feat surprised the researchers, who were initially sceptical about whether the ducklings could grasp such complex concepts as “same” and “different”. The fact that they could suggests the ability to think in an abstract way may be far more common in nature than expected, and not just restricted to humans and a handful of animals with big brains. “We were completely surprised,” says Alex Kacelnik at the University of Oxford, who conducted the experiment along with his colleague Antone Martinho III. Kacelnik and Martinho reasoned that ducklings might be able to grasp patterns relating to shape or colour as part of the array of sensory information they absorb soon after hatching. Doing so would allow them to recognise their mothers and siblings and distinguish them from all others – abilities vital for survival. In ducklings, goslings and other species that depend for survival on following their mothers, newborns learn quickly – a process called filial imprinting. Kacelnik wondered whether this would enable them to be tricked soon after hatching into “following” objects or colours instead of their natural mother, and recognising those same patterns in future. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 13: Memory, Learning, and Development
Link ID: 22443 - Posted: 07.15.2016

By Tanya Lewis In recent years, research on mammalian navigation has focused on the role of the hippocampus, a banana-shaped structure known to be integral to episodic memory and spatial information processing. The hippocampus’s primary output, a region called CA1, is known to be divided into superficial and deep layers. Now, using two-photon imaging in mice, researchers at Columbia University in New York have found these layers have distinct functions: superficial-layer neurons encode more-stable maps, whereas deep-layer brain cells better represent goal-oriented navigation, according to a study published last week (July 7) in Neuron. “There are lots of catalogued differences in sublayers of pyramidal cells” within the hippocampus, study coauthor Nathan Danielson of Columbia told The Scientist. “The question is, are the principle cells in each subregion doing the same thing? Or is there a finer level of granularity?” For that past few decades, scientists have been chipping away at an explanation of the brain’s “inner GPS.” The 2014 Nobel Prize in Physiology or Medicine honored the discovery of so-called place cells and grid cells in the hippocampus, which keep track of an individual’s location and coordinates in space, respectively. Since then, studies have revealed that neurons in different hippocampal regions have distinct genetic, anatomical, and physiological properties, said Attila Losonczy of Columbia, Danielson’s graduate advisor and a coauthor on the study. © 1986-2016 The Scientist

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 22437 - Posted: 07.14.2016