Links for Keyword: Learning & Memory

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By Susan Cosier Once a memory is lost, is it gone forever? Most research points to yes. Yet a study published in the online journal eLife now suggests that traces of a lost memory might remain in a cell's nucleus, perhaps enabling future recall or at least the easy formation of a new, related memory. The current theory accepted by neurobiologists is that long-term memories live at synapses, which are the spaces where impulses pass from one nerve cell to another. Lasting memories are dependent on a strong network of such neural connections; memories weaken or fade if the synapses degrade. In the new study, researchers at the University of California, Los Angeles, studied sea slugs' neurons in a cell culture dish. Over several days the neurons spontaneously formed a number of synapses. The scientists then administered the neurotransmitter serotonin to the neurons, causing them to create many more synapses—the same process by which a living creature would form a long-term memory. When they inhibited a memory-forming enzyme and checked the neurons after 48 hours, the number of synapses had returned to the initial number—but they were not the same individual synapses as before. Some of the original and some of the new synapses retracted to create the exact number the cells started with. The finding is surprising because it suggests that a nerve cell body “knows” how many synapses it is supposed to form, meaning it is encoding a crucial part of memory. The researchers also ran a similar experiment on live sea slugs, in which they found that a long-term memory could be totally erased (as gauged by its synapses being destroyed) and then re-formed with only a small reminder stimulus—again suggesting that some information was being stored in a neuron's body. © 2015 Scientific American

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 20958 - Posted: 05.20.2015

An octopus filmed off the coast of Kalaoa in Hawaii has shown that even cephalopods can get into a game of peekaboo. In the footage, shot last month by the GoPro camera of diver Timothy Ewing, the octopus bobs up and down behind a rock as a Ewing does the same in an effort to take the animal's picture. It's clear from the video that the octopus is wary of Ewing and his big, light-equipped camera — but the animal is also very curious. “Octopus are one of the more intelligent creatures in the ocean. Sometimes they are too curious for their own good. If you hide from them they will come out and look for you," the diver wrote in his online posting of the video. Ewing explained to CaliforniaDiver.com that the encounter wasn't limited to the time captured on his GoPro. "I was interacting with that octopus for about 10 minutes before I took the video," Ewing told CaliforniaDiver.com. "I normally mount my GoPro to my big camera housing, however I always carry a small tripod with me to use with the GoPro for stationary shots like this or selfie videos." The octopus, found worldwide in tropical, subtropical and temperate areas, is known for its smarts and striking ability to camouflage itself. When it feels threatened, pigment cells in its skin allow it to change color instantly to blend in with its surroundings. The animals can also adapt their skin texture and body posture to further match their background. © 2015 Discovery Communications, LLC.

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 1: Biological Psychology: Scope and Outlook
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 1: An Introduction to Brain and Behavior
Link ID: 20954 - Posted: 05.20.2015

RACHEL MARTIN, HOST: For most of her life, Cole Cohen had a hard time with all kinds of things. She'd get lost all of the time. She couldn't do math to save her life. The whole concept of time was hard for her to grasp. Her parents took her to doctor after doctor, and there were all kinds of tests and experiments with medication, but no real diagnosis until she was 26 years old. Cole Cohen got her first MRI and finally, there was an explanation. There was a hole in her brain; a hole in her brain the size of a lemon. Her memoir, titled "Head Case," is a darkly funny exploration of what that discovery meant to her. Cole Cohen joins us now. Thanks so much for being with us. COLE COHEN: Thank you for having me, Rachel. MARTIN: Let's talk about what life was like before this revelation. I mentioned your propensity to get lost. We're not talking about being in a new place and getting confuses as a lot of us might do. You got lost in, like, big box stores that you had been to before. Can you describe that sensation, that feeling of not knowing where you are in a situation like that? COHEN: Yeah. I know that sensation every time I go grocery shopping. You know, you want to get a jar of peanut butter. You have a memory of where that jar of peanut butter is, and I just don't have that in my brain. I don't store that information. So it's like a discovery every time. MARTIN: I'd love for you to read an example of one of the symptoms. You have a hard time with numbers, even references to numbers. And you write about this in the book when you're taking driver's ed. Do you mind reading that bit? © 2015 NPR

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 1: Biological Psychology: Scope and Outlook
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 1: An Introduction to Brain and Behavior
Link ID: 20942 - Posted: 05.18.2015

By JIM DWYER The real world of our memory is made of bits of true facts, surrounded by holes that we Spackle over with guesses and beliefs and crowd-sourced rumors. On the dot of 10 on Wednesday morning, Anthony O’Grady, 26, stood in front of a Dunkin’ Donuts on Eighth Avenue in Manhattan. He heard a ruckus, some shouts, then saw a police officer chase a man into the street and shoot him down in the middle of the avenue. Moments later, Mr. O’Grady spoke to a reporter for The New York Times and said the wounded man was in flight when he was shot. “He looked like he was trying to get away from the officers,” Mr. O’Grady said. Another person on Eighth Avenue then, Sunny Khalsa, 41, had been riding her bicycle when she saw police officers and the man. Shaken by the encounter, she contacted the Times newsroom with a shocking detail. “I saw a man who was handcuffed being shot,” Ms. Khalsa said. “And I am sorry, maybe I am crazy, but that is what I saw.” At 3 p.m. on Wednesday, the Police Department released a surveillance videotape that showed that both Mr. O’Grady and Ms. Khalsa were wrong. Contrary to what Mr. O’Grady said, the man who was shot had not been trying to get away from the officers; he was actually chasing an officer from the sidewalk onto Eighth Avenue, swinging a hammer at her head. Behind both was the officer’s partner, who shot the man, David Baril. And Ms. Khalsa did not see Mr. Baril being shot while in handcuffs; he is, as the video and still photographs show, freely swinging the hammer, then lying on the ground with his arms at his side. He was handcuffed a few moments later, well after he had been shot. © 2015 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: 20939 - Posted: 05.16.2015

By Jonathan Webb Science reporter, BBC News A cluster of cells in the brain of a fly can track the animal's orientation like a compass, a study has revealed. Fixed in place on top of a spherical treadmill, a fruit fly walked on the spot while neuroscientists peered into its brain using a microscope. Watching the neurons fire inside a donut-shaped brain region, they saw activity sweep around the ring to match the direction the animal was headed. Mammals have similar "head direction cells" but this is a first for flies. The findings are reported in the journal Nature. Crucially, the compass-like activity took place not only when the animal was negotiating a virtual-reality environment, in which screens gave the illusion of movement, but also when it was left in the dark. "The fly is using a sense of its own motion to pick up which direction it's pointed," said senior author Dr Vivek Jayaraman, from the Howard Hughes Medical Institute's Janelia Research Campus. In some other insects, such as monarch butterflies and locusts, brain cells have been observed firing in a way that reflects the animal's orientation to the pattern of polarised light in the sky - a "sun compass". But the newly discovered compass in the fly brain works more like the "head directions cells" seen in mammals, which rapidly set up a directional system for the animal based on landmarks in the surrounding scene. "A key thing was incorporating the fly's own movement," Dr Jayaraman told the BBC. "To see that its own motion was relevant to the functioning of this compass - that was something we could only see if we did it in a behaving animal." © 2015 BBC

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 20933 - Posted: 05.14.2015

Thomas R. Clandinin & Lisa M. Giocomo An analysis reveals that fruit-fly neurons orient flies relative to cues in the insects' environment, providing evidence that the fly's brain contains a key component for drawing a cognitive map of the insect's surroundings. See Article p.186 Animals need accurate navigational skills as they go about their everyday lives. Many species, from ants to rodents, navigate on the basis of visual landmarks, and this is complemented by path integration, in which neuronal cues about the animal's own motion are used to track its location relative to a starting point. In mammals, these different types of navigation are integrated by neurons called head-direction cells1. In this issue, Seelig and Jayaraman2 (page 186) provide the first evidence that certain neurons in fruit flies have similar properties to head-direction cells, encoding information that orients the insects relative to local landmarks. Head-direction cells act as a neuronal compass that generates a cognitive map of an animal's environment. The activity of each head-direction cell increases as the animal faces a particular direction, with different cells preferentially responding to different directions1, 3. Rather than certain cells always responding to north, south and so on, the direction in which the cells fire is set up arbitrarily when the animal encounters new visual landmarks. The signals are then updated by self-motion cues as the animal navigates. Studying head-direction cells in mammals is challenging because of the complexity of the mammalian brain. By contrast, the small fly brain is a good model for studying neuronal activity. © 2015 Macmillan Publishers Limited.

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 20932 - Posted: 05.14.2015

By Gareth Cook Much has been written on the wonders of human memory: the astounding feats of recall, the way memories shape our identity and are shaped by them, memory as a literary theme and a historical one. But what of forgetting? This is the topic of a new book by Douwe Draaisma, author of The Nostalgia Factory and a professor of the history of psychology at the University of Groningen. In Forgetting, Draaisma considers dreaming, amnesia, dementia and all of the ways that our minds — and lives — are shaped by memory’s opposite. He answered questions from Mind Matters editor Gareth Cook. What is your earliest memory and why, do you suppose, have you not forgotten it? Quite a few early memories in the Netherlands involve bicycles, and mine is no exception. I was two-and-a-half years old when my aunts walked my mother to the train station. They had taken a bike along to transport her bags. I was sitting on the back of the bike. Suddenly the whole procession came to a halt when my foot got caught between the spokes. I’m pretty sure this memory is accurate, since I had to see a doctor and there is a dated medical record. It’s a brief, snapshot-like memory, black-and-white. I don’t remember any pain, but I do remember the consternation among my mom and her sisters. Looking back on this memory from a professional perspective, I would say that it has the flash-like character typical for first memories from before age 3; ‘later’ first memories are usually a bit longer and more elaborate. It also fits the pattern of being about pain and danger. Roughly three in four first memories are associated with negative emotions. This may have an evolutionary origin: I never again had my foot between the spokes. And neither have any of my children. © 2015 Scientific American

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 20918 - Posted: 05.13.2015

By Simon Makin After wandering around an unfamiliar part of town, can you sense which direction to travel to get back to the subway or your car? If so, you can thank your entorhinal cortex, a brain area recently identified as being responsible for our sense of direction. Variation in the signals in this area might even explain why some people are better navigators than others. The new work adds to a growing understanding of how our brain knows where we are. Groundbreaking discoveries in this field won last year's Nobel Prize in Physiology or Medicine for John O'Keefe, a neuroscientist at University College London, who discovered “place cells” in the hippocampus, a brain region most associated with memory. These cells activate when we move into a specific location, so that groups of them form a map of the environment. O'Keefe shared the prize with his former students Edvard Moser and May-Britt Moser, both now at the Kavli Institute for Systems Neuroscience in Norway, who discovered “grid cells” in the entorhinal cortex, a region adjacent to the hippocampus. Grid cells have been called the brain's GPS system. They are thought to tell us where we are relative to where we started. A third type—head-direction cells, also found in the entorhinal region—fires when we face a certain direction (such as “toward the mountain”). Together these specialized neurons appear to enable navigation, but precisely how is still unclear. For instance, in addition to knowing which direction we are facing, we need to know which direction to travel. Little was known about how or where such a goal-direction signal might be generated in the brain until the new study. © 2015 Scientific American

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 20915 - Posted: 05.13.2015

Jane Brody With people worldwide living longer, marketers are seizing on every opportunity to sell remedies and devices that they claim can enhance memory and other cognitive functions and perhaps stave off dementia as people age. Among them are “all-natural” herbal supplements like Luminene, with ingredients that include the antioxidant alpha lipoic acid, the purported brain stimulant ginkgo biloba, and huperzine A, said to increase levels of the neurotransmitter acetylcholine; brain-training games on computers and smartphones; and all manner of puzzles, including crosswords, sudoku and jigsaw, that give the brain a workout, albeit a sedentary one. Unfortunately, few such potions and gizmos have been proven to have a meaningful, sustainable benefit beyond lining the pockets of their sellers. Before you invest in them, you’d be wise to look for well-designed, placebo-controlled studies that attest to their ability to promote a youthful memory and other cognitive functions. Even the widely acclaimed value of doing crossword puzzles has been called into question, beyond its unmistakable benefit to one’s font of miscellaneous knowledge. Although there is some evidence that doing crosswords may help to delay memory decline, Molly Wagster, a neuroscientist at the National Institute on Aging, said they are best done for personal pleasure, not brain health. “People who have done puzzles all their lives have no particular cognitive advantage over anyone else,” she said. The institute is one of several scientific organizations sponsoring rigorous trials of ways to cash in on the brain’s lifelong ability to generate new cells and connections. One such trial, Advanced Cognitive Training for Independent and Vital Elderly, or Active, was a 10-year follow-up study of 2,832 cognitively healthy community-dwelling adults 65 and older. © 2015 The New York Times Company

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: 20910 - Posted: 05.12.2015

Andrew Griffin Scientists have created an electronic memory cell that mimics the way that human brains work, potentially unlocking the possibility of the making bionic brains. The cell can process and store multiple bits of information, like the human brain. Scientists hope that developing it could make for artificial cells that simulate the brain’s processes, leading to treatments for neurological conditions and for replica brains that scientists can experiment on. The new cells have been likened to the difference between having an on-off light switch and a dimmer, or the difference between black and white pictures or those with full colour, including shade light and texture. While traditional memory cells for computers can only process one binary thing at a time, the new discovery allows for much more complex memory processes like those found in the brain. They are also able to retain previous information, allowing for artificial systems that have the extraordinary memory powers found in human beings. While the new discovery is a long way from leading to a bionic brain, the discovery is an important step towards the dense and fast memory cells that will be needed to imitate the human brain's processes. “This is the closest we have come to creating a brain-like system with memory that learns and stores analog information and is quick at retrieving this stored information,” Sharath Sriram, who led the project, said.

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 20909 - Posted: 05.12.2015

Neuroscientists have discovered brain circuitry for encoding positive and negative learned associations in mice. After finding that two circuits showed opposite activity following fear and reward learning, the researchers proved that this divergent activity causes either avoidance or reward-driven behaviors. Funded by the National Institutes of Health, they used cutting-edge optical-genetic tools to pinpoint these mechanisms critical to survival, which are also implicated in mental illness. “This study exemplifies the power of new molecular tools that can push and pull on the same circuit to see what drives behavior,” explained Thomas R. Insel, M.D., director of NIH’s National Institute of Mental Health (NIMH). “Improved understanding of how such emotional memory works holds promise for solving mysteries of brain circuit disorders in which these mechanisms are disrupted.” NIMH grantee Kay Tye, Ph.D. External Web Site Policy, Praneeth Namburi and Anna Beyeler, Ph.D., of the Massachusetts Institute of Technology (MIT), Cambridge, and colleagues, report their findings April 29, 2015 in the journal Nature. Prior to the new study, scientists suspected involvement of the circuits ultimately implicated, but were stumped by a seeming paradox. A crossroads of convergent circuits in an emotion hub deep in the brain, thebasolateral amygdala, seem to be involved in both fear and reward learning, but how one brain region could orchestrate such opposing behaviors – approach and avoidance – remained an enigma. How might signals find the appropriate path to follow at this fork in the road?

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 11: Emotions, Aggression, and Stress
Link ID: 20866 - Posted: 04.30.2015

Pete Etchells Over the past few years, there seems to have been a insidious pandemic of nonsense neuroscientific claims creeping into the education system. In 2013, the Wellcome Trust commissioned a series of surveys of parents and teachers, asking about various types of educational tools or teaching methods, and the extent to which they believe they have a basis in neuroscience. Worryingly, 76% of teachers responded that they used learning styles in their teaching, and a further 19% responded that they either use, or intend to use, left brain/right brain distinctions to help inform learning methods. Both of these approaches have been thoroughly debunked, and have no place in either neuroscience or education. In October last year, I reported on another study that showed that in the intervening time, things hadn’t really improved – 91% of UK teachers in that survey believed that there were differences in the way that students think and learn, depending on which hemisphere of the brain is ‘dominant’. And despite lots of great attempts to debunk myths about the brain, they still seem to persist and take up residence as ‘commonplace’ knowledge, being passed onto children as if they are fact. When I wrote about an ATL proposal to train teachers in neuroscience – a well-intended idea, but ultimately grounded in nonsense about left brain/right brain myths – I commented at the end that we need to do more to bring teachers and neuroscientists together, to discuss whether neuroscience has a relevant role in informing the way we teach students. Now, a new initiative funded by the Wellcome Trust is aiming to just that. © 2015 Guardian News and Media Limited

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: 20845 - Posted: 04.25.2015

By Felicity Muth One of the first things I get asked when I tell people that I work on bee cognition (apart from ‘do you get stung a lot?’) is ‘bees have cognition?’. I usually assume that this question shouldn’t be taken literally otherwise it would mean that whoever was asking me this thought that there was a possibility that bees didn’t have cognition and I had just been making a terrible mistake for the past two years. Instead I guess this question actually means ‘please tell me more about the kind of cognitive abilities bees have, as I am very much surprised to hear that bees can do more than just mindlessly sting people’. So, here it is: a summary of some of the more remarkable things that bees can do with their little brains. In the first part of two articles on this topic, I introduce the history and basics of bee learning. In the second article, I go on to discuss the more advanced cognitive abilities of bees. The study of bee cognition isn’t a new thing. Back in the early 1900s the Austrian scientist Karl von Frisch won the Nobel Prize for his work with honeybees (Apis mellifera). He is perhaps most famous for his research on their remarkable ability to communicate through the waggle dance but he also showed for the first time that honeybees have colour vision and learn the colours of the flowers they visit. Appreciating how he did this is perhaps the first step to understanding everything we know about bee cognition today. Before delving into the cognitive abilities of bees it’s important to think about what kinds of abilities a bee might need, given the environment she lives in (all foraging worker bees are female). Bees are generalists, meaning that they don’t have to just visit one particular flower type for food (nectar and pollen), but can instead visit hundreds of different types. However, not all flowers are the same. © 2015 Scientific American,

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 20831 - Posted: 04.22.2015

By Alix Spiegel In 1979, when Jim Stigler was still a graduate student at the University of Michigan, he went to Japan to research teaching methods and found himself sitting in the back row of a crowded fourth-grade math class. “The teacher was trying to teach the class how to draw three-dimensional cubes on paper,” Stigler explains, “and one kid was just totally having trouble with it. His cube looked all cockeyed, so the teacher said to him, ‘Why don’t you go put yours on the board?’ So right there I thought, ‘That’s interesting! He took the one who can’t do it and told him to go and put it on the board.’ ” Stigler knew that in American classrooms, it was usually the best kid in the class who was invited to the board. And so he watched with interest as the Japanese student dutifully came to the board and started drawing, but still couldn’t complete the cube. Every few minutes, the teacher would ask the rest of the class whether the kid had gotten it right, and the class would look up from their work, and shake their heads no. And as the period progressed, Stigler noticed that he — Stigler — was getting more and more anxious. In Japanese classrooms, teachers consciously design tasks that are slightly beyond the capabilities of the students they teach, so the students can actually experience struggling with something just outside their reach. “I realized that I was sitting there starting to perspire,” he says, “because I was really empathizing with this kid. I thought, ‘This kid is going to break into tears!’ ” © 2015 KQED Inc.

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 20820 - Posted: 04.20.2015

By Megan Griffith-Greene The idea of playing a game to make you sharper seems like a no-brainer. That's the thinking behind a billion-dollar industry selling brain training games and programs designed to boost cognitive ability. But an investigation by CBC's Marketplace reveals that brain training games such as Lumosity may not make your brain perform better in everyday life. Lumosity Brain training games, such as Lumosity, are a billion-dollar industry. Many people are worried about maintaining their brain health and want to prevent a decline in their mental abilities. (CBC) Almost 15 per cent of Canadians over the age of 65 are affected by some kind of dementia. And many people of all ages are worried about maintaining their brain health and possibly preventing a decline in their mental abilities. "I don't think there's anything to say that you can train your brain to be cognitively better in the way that we know that we can train our bodies to be physically better," neuroscientist Adrian Owen told Marketplace co-host Tom Harrington. To test how effective the games are at improving cognitive function, Marketplace partnered with Owen, who holds the Canada Excellence Research Chair in Cognitive Neuroscience and Imaging at the Brain and Mind Institute at Western University. A group of 54 adults, including Harrington, did the brain training at least three times per week for 15 minutes or more over a period of between two and a half and four weeks. The group underwent a complete cognitive assessment at the beginning and end of the training to see if there had been any change as the result of the training program. ©2015 CBC/Radio-Canada.

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: 20774 - Posted: 04.10.2015

Alison Abbott Historian of psychology Douwe Draaisma knows well how to weave science, history and literature into irresistible tales. Forgetting, his latest collection of essays around the theme of memory, is — like his successful Nostalgia Factory (Yale University Press, 2013) — hard to put down. His vivid tour through the history of memory-repression theories brings home how dangerous and wrong, yet persistent, were the ideas of Sigmund Freud and his intellectual heirs. Freud thought that traumatic memories and shameful thoughts could be driven from the consciousness, but not forgotten. They would simmer in the unconscious, influencing behaviour. He maintained that forcing them out with psychoanalysis, and confronting patients with them, would be curative. Draaisma relates the case of an 18-year-old whom Freud dubbed Dora, diagnosed in 1900 with 'hysteria'. Dora's family refused to believe that the husband of her father's mistress had made sexual advances to her. Among other absurdities, Freud told Dora that her nervous cough reflected her repressed desire to fellate the man. Dora broke off the therapy, which Freud saw as proof of his theory. He thought that patients will naturally resist reawakening painful thoughts. What Dora did not buy, plenty of others did. Psychoanalysis boomed, becoming lucrative. Its principles were adopted in the 1990s by an unlikely alliance of lawyers and some feminists, who argued that repressed memories of childhood abuse could be recovered with techniques such as hypnosis, and used as evidence in court. Many judges went along with it; the rush of claims cast a shadow over genuine cases of abuse, Draaisma points out. We now know from studies of post-traumatic stress disorder that traumatic memories are impossible to repress. They flood into the conscious mind in horrifying flashbacks. © 2015 Macmillan Publishers Limited

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 20747 - Posted: 04.02.2015

|By Dwayne Godwin and Jorge Cham Our minds are veritable memory machines. © 2015 Scientific American

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 20734 - Posted: 03.31.2015

|By Roni Jacobson As intangible as they may seem, memories have a firm biological basis. According to textbook neuroscience, they form when neighboring brain cells send chemical communications across the synapses, or junctions, that connect them. Each time a memory is recalled, the connection is reactivated and strengthened. The idea that synapses store memories has dominated neuroscience for more than a century, but a new study by scientists at the University of California, Los Angeles, may fundamentally upend it: instead memories may reside inside brain cells. If supported, the work could have major implications for the treatment of post-traumatic stress disorder (PTSD), a condition marked by painfully vivid and intrusive memories. More than a decade ago scientists began investigating the drug propranolol for the treatment of PTSD. Propranolol was thought to prevent memories from forming by blocking production of proteins required for long-term storage. Unfortunately, the research quickly hit a snag. Unless administered immediately after the traumatic event, the treatment was ineffective. Lately researchers have been crafting a work-around: evidence suggests that when someone recalls a memory, the reactivated connection is not only strengthened but becomes temporarily susceptible to change, a process called memory reconsolidation. Administering propranolol (and perhaps also therapy, electrical stimulation and certain other drugs) during this window can enable scientists to block reconsolidation, wiping out the synapse on the spot. The possibility of purging recollections caught the eye of David Glanzman, a neurobiologist at U.C.L.A., who set out to study the process in Aplysia, a sluglike mollusk commonly used in neuroscience research. Glanzman and his team zapped Aplysia with mild electric shocks, creating a memory of the event expressed as new synapses in the brain. The scientists then transferred neurons from the mollusk into a petri dish and chemically triggered the memory of the shocks in them, quickly followed by a dose of propranolol. © 2015 Scientific American

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 12: Psychopathology: Biological Basis of Behavioral Disorders
Link ID: 20732 - Posted: 03.30.2015

By PAM BELLUCK What happens to forgotten memories — old computer passwords, friends’ previous phone numbers? Scientists have long held two different theories. One is that memories do not diminish but simply get overshadowed by new memories. The other is that older memories become weaker, that pulling to mind new passwords or phone numbers degrades old recollections so they do not interfere. The difference could be significant. If old memories stay strong and are merely papered over by new ones, they may be easier to recover. That could be positive for someone trying to remember an acquaintance’s name, but difficult for someone trying to lessen memories of abuse. It could suggest different strategies for easing traumatic memories, evaluating witness testimony about crimes, or helping students study for tests. Now, a study claims to provide evidence of memory’s weakening by showing that people’s ability to remember something and the pattern of brain activity that thing generates both appear to diminish when a competing memory gets stronger. Demonstrating sophisticated use of brain scans in memory research, authors of the study, published Monday in the journal Nature Neuroscience, appear to have identified neural fingerprints of specific memories, distinguishing brain activity patterns produced when viewing a picture of a necklace, say, from a picture of binoculars or other objects. The experiment, conducted by scientists in Birmingham and Cambridge, England, involved several stages with 24 participants first trained to associate words to two unrelated black and white pictures from lists of famous people, ordinary objects or scenes. © 2015 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: 20695 - Posted: 03.17.2015

By Douglas Starr In 1906, Hugo Münsterberg, the chair of the psychology laboratory at Harvard University and the president of the American Psychological Association, wrote in the Times Magazine about a case of false confession. A woman had been found dead in Chicago, garroted with a copper wire and left in a barnyard, and the simpleminded farmer’s son who had discovered her body stood accused. The young man had an alibi, but after questioning by police he admitted to the murder. He did not simply confess, Münsterberg wrote; “he was quite willing to repeat his confession again and again. Each time it became richer in detail.” The young man’s account, he continued, was “absurd and contradictory,” a clear instance of “the involuntary elaboration of a suggestion” from his interrogators. Münsterberg cited the Salem witch trials, in which similarly vulnerable people were coerced into self-incrimination. He shared his opinion in a letter to a Chicago nerve specialist, which made the local press. A week later, the farmer’s son was hanged. Münsterberg was ahead of his time. It would be decades before the legal and psychological communities began to understand how powerfully suggestion can shape memory and, in turn, the course of justice. In the early nineteen-nineties, American society was recuperating from another panic over occult influence; Satanists had replaced witches. One case, the McMartin Preschool trial, hinged on nine young victims’ memories of molestation and ritual abuse—memories that they had supposedly forgotten and then, after being interviewed, recovered. The case fell apart, in 1990, because the prosecution could produce no persuasive evidence of the victims’ claims. A cognitive psychologist named Elizabeth Loftus, who had consulted on the case, wondered whether the children’s memories might have been fabricated—in Münsterberg’s formulation, involuntarily elaborated—rather than actually recovered.

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 20679 - Posted: 03.12.2015