Your memory is no video camera: It edits the past with present experiences

Your memory is a wily time traveler, plucking fragments of the present and inserting them into the past, reports a new Northwestern Medicine study. In terms of accuracy, it’s no video camera.Rather, the memory rewrites the past with current information, updating your recollections with new experiences.Love at first sight, for example, is more likely a trick of your memory than a Hollywood-worthy moment.”When you think back to when you met your current partner, you may recall this feeling of love and euphoria,” said lead author Donna Jo Bridge, a postdoctoral fellow in medical social sciences at Northwestern University Feinberg School of Medicine. “But you may be projecting your current feelings back to the original encounter with this person.”The study will be published Feb. 5 in the Journal of Neuroscience.This the first study to show specifically how memory is faulty, and how it can insert things from the present into memories of the past when those memories are retrieved. The study shows the exact point in time when that incorrectly recalled information gets implanted into an existing memory.To help us survive, Bridge said, our memories adapt to an ever-changing environment and help us deal with what’s important now.”Our memory is not like a video camera,” Bridge said. “Your memory reframes and edits events to create a story to fit your current world. It’s built to be current.”All that editing happens in the hippocampus, the new study found. The hippocampus, in this function, is the memory’s equivalent of a film editor and special effects team.For the experiment, 17 men and women studied 168 object locations on a computer screen with varied backgrounds such as an underwater ocean scene or an aerial view of Midwest farmland. Next, researchers asked participants to try to place the object in the original location but on a new background screen. Participants would always place the objects in an incorrect location.For the final part of the study, participants were shown the object in three locations on the original screen and asked to choose the correct location. …

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Retrieval practice improves memory in severe traumatic brain injury, researchers demonstrate

Kessler Foundation researchers have shown that retrieval practice can improve memory in individuals with severe traumatic brain injury (TBI). “Retrieval Practice Improves Memory in Survivors of Severe Traumatic Brain Injury,” was published as a brief report in the current issue of Archives of Physical Medicine & Rehabilitation in February 2014. The article is authored by James Sumowski, PhD, Julia Coyne, PhD, Amanda Cohen, BA, and John DeLuca, PhD, of Kessler Foundation.”Despite the small sample size, it was clear that retrieval practice (RP) was superior to other learning strategies in this group of memory-impaired individuals with severe TBI,” explained Dr. Sumowski.Researchers studied ten patients with severe TBI and memory impairment (<5<sup>th percentile) to see whether RP improved memory after short (30 min) and long (1 week) delays. During RP, also described as testing effect, patients are quizzed shortly after information to be learned is presented. RP was compared with two other learning strategies–massed restudy (MR), which consists of repeated restudy (ie, cramming) and spaced restudy (SR), for which individuals restudy information at intervals (ie, distributed learning).Results showed that recall was better with RP than with MR or SR. Moreover, RP was more effective for memory after short delay, and was the only strategy that supported memory after long delay. This robust effect indicates that RP would improve memory in this group in real-life settings. “If these individuals learn to incorporate this compensatory strategy into their daily routines, they can improve their memory,” Dr. Sumowski noted. …

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Aerobic fitness boosts learning, memory in 9-10-year-old children

Sep. 11, 2013 — Physical fitness can boost learning and memory in children, particularly when initial learning on a task is more challenging, according to research published September 11 in the open access journal PLOS ONE by Lauren Raine and colleagues from the University of Illinois at Urbana-Champaign.Share This:Forty-eight children aged nine to ten were asked to memorize names and locations on a fictitious map, either only by studying the information or being tested on the material as they studied. Half the children were in the top 30% of their age group on a test measuring aerobic fitness, while the other half scored in the lowest 30 percent. When asked to recollect the information studied, children who were fitter performed better than those who were not as fit.The difference between the high-fitness and low-fitness groups was also stronger when the initial learning was performed by studying alone than when testing and study were interspersed. Previous studies have suggested that combining testing and study improves later recall in children, and is less challenging than studying alone. Based on these results, the authors suggest that fitness levels may influence learning differently when the study method used is more challenging, and that higher levels of aerobic fitness can benefit learning and memory in school-age children. They conclude, “Future research should focus on the manner in which these factors impact the neural processes of children during learning.”In addition, the study suggests these findings may be important from an educational policy perspective. As the authors state, “Reducing or eliminating physical education in schools, as is often done in tight financial times, may not be the best way to ensure educational success among our young people.”Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is based on materials provided by Public Library of Science. Note: Materials may be edited for content and length. For further information, please contact the source cited above. …

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Brain circuitry loss may be an early sign of cognitive decline

Sep. 9, 2013 — The degeneration of a small, wishbone-shaped structure deep inside the brain may provide the earliest clues to future cognitive decline, long before healthy older people exhibit clinical symptoms of memory loss or dementia, a study by researchers with the UC Davis Alzheimer’s Disease Center has found.The longitudinal study found that the only discernible brain differences between normal people who later developed cognitive impairment and those who did not were changes in their fornix, an organ that carries messages to and from the hippocampus, and that has long been known to play a role in memory.”This could be a very early and useful marker for future incipient decline,” said Evan Fletcher, the study’s lead author and a project scientist with the UC Davis Alzheimer’s Disease Center.”Our results suggest that fornix variables are measurable brain factors that precede the earliest clinically relevant deterioration of cognitive function among cognitively normal elderly individuals,” Fletcher said.The research is published online today in JAMA Neurology.Hippocampal atrophy occurs in the later stages of cognitive decline and is one of the most studied changes associated with the Alzheimer’s disease process. However, changes to the fornix and other regions of the brain structurally connected to the hippocampus have not been as closely examined. The study found that degeneration of the fornix in relation to cognition was detectable even earlier than changes in the hippocampus.”Although hippocampal measures have been studied much more deeply in relation to cognitive decline, our direct comparison between fornix and hippocampus measures suggests that fornix properties have a superior ability to identify incipient cognitive decline among healthy individuals,” Fletcher said.The study was conducted over five years in a group of 102 diverse, cognitively normal people with an average age of 73 who were recruited through community outreach at the Alzheimer’s Disease Center. The researchers conducted magnetic resonance imaging (MRI) studies of the participants’ brains that described their volumes and integrity. A different type of MRI was used to determine the integrity of the myelin, the fatty coating that sheaths and protects the axons. The axons are analogous to the copper wiring of the brain’s circuitry and the myelin is like the wiring’s plastic insulation.Either one of those things being lost will “degrade the signal transmission” in the brain, Fletcher said.The researchers also conducted psychological tests and cognitive evaluations of the study participants to gauge their level of cognitive functioning. The participants returned for updated MRIs and cognitive testing at approximately one-year intervals. At the outset, none of the study participants exhibited symptoms of cognitive decline. Over time about 20 percent began to show symptoms that led to diagnoses with either mild cognitive impairment (MCI) and, in a minority of cases, Alzheimer’s disease.”We found that if you looked at various brain factors there was one — and only one — that seemed to be predictive of whether a person would have cognitive decline, and that was the degradation of the fornix,” Fletcher said.The study measured two relevant fornix characteristics predicting future cognitive impairment — low fornix white matter volume and reduced axonal integrity. …

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Intricacies of lying: False descriptions easier to remember than false denials

Sep. 4, 2013 — What happens when you tell a lie? Set aside your ethical concerns for a moment — after all, lying is a habit we practice with astonishing dexterity and frequency, whether we realize it or not. What goes on in your brain when you willfully deceive someone? And what happens later, when you attempt to access the memory of your deceit? How you remember a lie may be impacted profoundly by how you lie, according to a new study by LSU Associate Professor Sean Lane and former graduate student Kathleen Vieria.The study, accepted for publication in the Journal of Applied Research and Memory Cognition, examines two kinds of lies — false descriptions and false denials — and the different cognitive machinery that we use to record and retrieve them.False descriptions are deliberate flights of the imagination — details and descriptions that we invent for something that didn’t happen. As it turned out, these lies were far easier for Lane’s test subjects to remember.Lane explained that false descriptions remain more accessible and more durable in our memories because they tax our cognitive power.”If I’m going to lie to you about something that didn’t happen, I’m going to have to keep a lot of different constraints in mind,” Lane said.Liars must remember what they say, and also monitor how plausible they seem, the depth of detail they offer, even how confident they appear to the listener. And if the listener doesn’t seem to be buying it, they must adapt the story accordingly.”As the constructive process lays down records of our details and descriptions, it also lays down information about the process of construction,” Lane said.In short, false descriptions take work. We remember them well precisely because of the effort required to make them up. When subjects in Lane’s study were asked to recall their own false descriptions 48 hours later, their memories were largely accurate. …

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Psychologist discovers intricacies about lying

Sep. 4, 2013 — What happens when you tell a lie? Set aside your ethical concerns for a moment — after all, lying is a habit we practice with astonishing dexterity and frequency, whether we realize it or not. What goes on in your brain when you willfully deceive someone? And what happens later, when you attempt to access the memory of your deceit? How you remember a lie may be impacted profoundly by how you lie, according to a new study by LSU Associate Professor Sean Lane and former graduate student Kathleen Vieria. The study, accepted for publication in the Journal of Applied Research and Memory Cognition, examines two kinds of lies — false descriptions and false denials — and the different cognitive machinery that we use to record and retrieve them.False descriptions are deliberate flights of the imagination — details and descriptions that we invent for something that didn’t happen. As it turned out, these lies were far easier for Lane’s test subjects to remember.Lane explained that false descriptions remain more accessible and more durable in our memories because they tax our cognitive power.”If I’m going to lie to you about something that didn’t happen, I’m going to have to keep a lot of different constraints in mind,” Lane said.Liars must remember what they say, and also monitor how plausible they seem, the depth of detail they offer, even how confident they appear to the listener. And if the listener doesn’t seem to be buying it, they must adapt the story accordingly.”As the constructive process lays down records of our details and descriptions, it also lays down information about the process of construction,” Lane said.In short, false descriptions take work. We remember them well precisely because of the effort required to make them up. …

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Experimental compound reverses down syndrome-like learning deficits in mice

Sep. 4, 2013 — Researchers at Johns Hopkins and the National Institutes of Health have identified a compound that dramatically bolsters learning and memory when given to mice with a Down syndrome-like condition on the day of birth. As they report in the Sept. 4 issue of Science Translational Medicine, the single-dose treatment appears to enable the cerebellum of the rodents’ brains to grow to a normal size.The scientists caution that use of the compound, a small molecule known as a sonic hedgehog pathway agonist, has not been proven safe to try in people with Down syndrome, but say their experiments hold promise for developing drugs like it.”Most people with Down syndrome have a cerebellum that’s about 60 percent of the normal size,” says Roger Reeves, Ph.D., a professor in the McKusick-Nathans Institute of Genetic Medicine at the Johns Hopkins University School of Medicine. “We treated the Down syndrome-like mice with a compound we thought might normalize the cerebellum’s growth, and it worked beautifully. What we didn’t expect were the effects on learning and memory, which are generally controlled by the hippocampus, not the cerebellum.”Reeves has devoted his career to studying Down syndrome, a condition that occurs when people have three, rather than the usual two, copies of chromosome 21. As a result of this “trisomy,” people with Down syndrome have extra copies of the more than 300 genes housed on that chromosome, which leads to intellectual disabilities, distinctive facial features and sometimes heart problems and other health effects. Since the condition involves so many genes, developing treatments for it is a formidable challenge, Reeves says.For the current experiments, Reeves and his colleagues used mice that were genetically engineered to have extra copies of about half of the genes found on human chromosome 21. The mice have many characteristics similar to those of people with Down syndrome, including relatively small cerebellums and difficulty learning and remembering how to navigate through a familiar space. (In the case of the mice, this was tested by tracking how readily the animals located a platform while swimming in a so-called water maze.) Based on previous experiments on how Down syndrome affects brain development, the researchers tried supercharging a biochemical chain of events known as the sonic hedgehog pathway that triggers growth and development. …

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Art preserves skills despite onset of vascular dementia in ‘remarkable’ case of a Canadian sculptor

Aug. 22, 2013 — The ability to draw spontaneously as well as from memory may be preserved in the brains of artists long after the deleterious effects of vascular dementia have diminished their capacity to complete simple, everyday tasks, according to a new study by physicians at St. Michael’s Hospital.The finding, scheduled to be released today in the Canadian Journal of Neurological Sciences, looked at the last few years of the late Mary Hecht, an internationally renowned sculptor, who was able to draw spur-of-the moment and detailed sketches of faces and figures, including from memory, despite an advanced case of vascular dementia.”Art opens the mind,” said Dr. Luis Fornazzari, neurological consultant at St. Michael’s Hospital’s Memory Clinic and lead author of the paper. “Mary Hecht was a remarkable example of how artistic abilities are preserved in spite of the degeneration of the brain and a loss in the more mundane, day-to-day memory functions.”Hecht, who died in April 2013 at 81, had been diagnosed with vascular dementia and was wheelchair-bound due to previous strokes. Despite her vast knowledge of art and personal talent, she was unable to draw the correct time on a clock, name certain animals or remember any of the words she was asked to recall.But she quickly sketched an accurate portrait of a research student from the Memory Clinic. And she was able to draw a free-hand sketch of a lying Buddha figurine and reproduce it from memory a few minutes later. To the great delight of St. Michael’s doctors, Hecht also drew an accurate sketch of famed cellist Mstislav Rostropovich after she learned of his death earlier that day on the radio.While she was drawing and showing medical staff her own creations, Hecht spoke eloquently and without hesitation about art.”This is the most exceptional example of the degree of preservation of artistic skills we’ve seen in our clinic,” said Dr. …

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Newly discovered ‘switch’ plays dual role in memory formation

Aug. 13, 2013 — Researchers at Johns Hopkins have uncovered a protein switch that can either increase or decrease memory-building activity in brain cells, depending on the signals it detects. Its dual role means the protein is key to understanding the complex network of signals that shapes our brain’s circuitry, the researchers say. A description of their discovery appears in the July 31 issue of the Journal of Neuroscience.Share This:”What’s interesting about this protein, AGAP3, is that it is effectively double-sided: One side beefs up synapses in response to brain activity, while the other side helps bring synapse-building back down to the brain’s resting state,” says Rick Huganir, Ph.D., a professor and director of the Solomon H. Snyder Department of Neuroscience at the Johns Hopkins University School of Medicine and co-director of the Brain Science Institute at Johns Hopkins. “The fact that it links these two opposing activities indicates AGAP3 may turn out to be central to controlling the strength of synapses.”Huganir has long studied how connections between brain cells, known as synapses, are strengthened and weakened to form or erase memories. The new discovery came about when he and postdoctoral fellow Yuko Oku, Ph.D., investigated the chain reaction of signals involved in one type of synaptic strengthening.In a study of the proteins that interact with one of the known proteins from that chain reaction, the previously unknown AGAP3 turned up. It contained not only a site designed to bind another protein involved in the chain reaction that leads from brain stimulation to learning, but also a second site involved in bringing synapse-building activity down to normal levels after a burst of activity. Although it might seem the two different functions are behaving at cross-purposes, Oku says, it also could be that nature’s bundling of these functions together in a single protein is an elegant way of enabling learning and memory while preventing dangerous overstimulation. More research is needed, Oku says, to figure out whether AGAP3’s two sites coordinate by affecting each other’s activity, or are effectively free agents.Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is based on materials provided by Johns Hopkins Medicine, via EurekAlert!, a service of AAAS. …

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Dolphins keep lifelong social memories, longest in a non-human species

Aug. 6, 2013 — Dolphins can recognize their old tank mates’ whistles after being separated for more than 20 years — the longest social memory ever recorded for a non-human species.The remarkable memory feat is another indication that dolphins have a level of cognitive sophistication comparable to only a few other species, including humans, chimpanzees and elephants. Dolphins’ talent for social recognition may be even more long-lasting than facial recognition among humans, since human faces change over time but the signature whistle that identifies a dolphin remains stable over many decades.”This shows us an animal operating cognitively at a level that’s very consistent with human social memory,” said Jason Bruck, who conducted the study and received his Ph.D. in June 2013 from the University of Chicago’s program in Comparative Human Development. His study is published in the current issue of the Proceedings of the Royal Society of London B.To establish how well dolphins could remember their former companions, Bruck collected data from 53 different bottlenose dolphins at six facilities, including Brookfield Zoo near Chicago and Dolphin Quest in Bermuda. The six sites were part of a breeding consortium that has rotated dolphins and kept records on which ones lived together, going back decades.”This is the kind of study you can only do with captive groups when you know how long the animals have been apart,” Bruck said. “To do a similar study in the wild would be almost impossible.””Signature whistles” offer means to test memoryIn recent years, other studies have established that each dolphin develops its own unique signature whistle that appears to function as a name. Researchers Vincent M. Janik and Stephanie L. King at Scotland’s University of St. …

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Neuroscientists plant false memories in mice: Location where brain stores memory traces, both false and authentic, pinpointed

July 25, 2013 — The phenomenon of false memory has been well-documented: In many court cases, defendants have been found guilty based on testimony from witnesses and victims who were sure of their recollections, but DNA evidence later overturned the conviction.In a step toward understanding how these faulty memories arise, MIT neuroscientists have shown that they can plant false memories in the brains of mice. They also found that many of the neurological traces of these memories are identical in nature to those of authentic memories.”Whether it’s a false or genuine memory, the brain’s neural mechanism underlying the recall of the memory is the same,” says Susumu Tonegawa, the Picower Professor of Biology and Neuroscience and senior author of a paper describing the findings in the July 25 edition of Science.The study also provides further evidence that memories are stored in networks of neurons that form memory traces for each experience we have — a phenomenon that Tonegawa’s lab first demonstrated last year.Neuroscientists have long sought the location of these memory traces, also called engrams. In the pair of studies, Tonegawa and colleagues at MIT’s Picower Institute for Learning and Memory showed that they could identify the cells that make up part of an engram for a specific memory and reactivate it using a technology called optogenetics.Lead authors of the paper are graduate student Steve Ramirez and research scientist Xu Liu. Other authors are technical assistant Pei-Ann Lin, research scientist Junghyup Suh, and postdocs Michele Pignatelli, Roger Redondo and Tomas Ryan.Seeking the engramEpisodic memories — memories of experiences — are made of associations of several elements, including objects, space and time. These associations are encoded by chemical and physical changes in neurons, as well as by modifications to the connections between the neurons.Where these engrams reside in the brain has been a longstanding question in neuroscience. “Is the information spread out in various parts of the brain, or is there a particular area of the brain in which this type of memory is stored? This has been a very fundamental question,” Tonegawa says.In the 1940s, Canadian neurosurgeon Wilder Penfield suggested that episodic memories are located in the brain’s temporal lobe. When Penfield electrically stimulated cells in the temporal lobes of patients who were about to undergo surgery to treat epileptic seizures, the patients reported that specific memories popped into mind. Later studies of the amnesiac patient known as “H.M.” confirmed that the temporal lobe, including the area known as the hippocampus, is critical for forming episodic memories.However, these studies did not prove that engrams are actually stored in the hippocampus, Tonegawa says. To make that case, scientists needed to show that activating specific groups of hippocampal cells is sufficient to produce and recall memories.To achieve that, Tonegawa’s lab turned to optogenetics, a new technology that allows cells to be selectively turned on or off using light.For this pair of studies, the researchers engineered mouse hippocampal cells to express the gene for channelrhodopsin, a protein that activates neurons when stimulated by light. …

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Drinking alcohol during pregnancy affects learning and memory function in offspring?

July 19, 2013 — Maternal alcohol consumption during pregnancy has detrimental effects on fetal central nervous system development.Share This:Maternal alcohol consumption prior to and during pregnancy significantly affects cognitive functions in offspring, which may be related to changes in cyclin-dependent kinase 5 because it is associated with modulation of synaptic plasticity and impaired learning and memory.Prof. Ruiling Zhang and team from Xinxiang Medical University explored the correlation between cyclin-dependent kinase 5 expression in the hippocampus and neurological impairments following prenatal ethanol exposure, and found that prenatal ethanol exposure could affect cyclin-dependent kinase 5 and its activator p35 in the hippocampus of offspring rats.These findings, which reported in the Neural Regeneration Research, propose new insights into the mechanisms underlying the role of ethanol exposure in central nervous system injuries, and provide a new strategy for treating the consequences of prenatal ethanol exposure.Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is reprinted from materials provided by Neural Regeneration Research, via EurekAlert!, a service of AAAS. Note: Materials may be edited for content and length. For further information, please contact the source cited above. Journal Reference:shuang Li, Yan Zhang, Feng Zhu, Bin Zhang, Jianying Lin, Chunyang Xu, Wancai Yang, Wei Hao, Ruiling Zhang. A new treatment for cognitive disorders related to in utero exposure to alcohol. Neural Regeneration Research, Vol. 8, No. 18, 2013 DOI: 10.3969/j.issn.1673-5374.2013.18.008 Need to cite this story in your essay, paper, or report? Use one of the following formats: APA MLA Note: If no author is given, the source is cited instead.

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Aging stereotypes can hurt older adults’ memory

July 1, 2013 — Of the many negative stereotypes that exist about older adults, the most common is that they are forgetful, senile and prone to so-called “senior moments.” In fact, while cognitive processes do decline with age, simply reminding older adults about ageist ideas actually exacerbates their memory problems, reveals important new research from the USC Davis School of Gerontology.The study, forthcoming in the journal Psychological Science, is an extension of the idea of “stereotype threat” — that when people are confronted with negative stereotypes about a group with which they identify, they tend to self-handicap and underperform compared to their potential. In doing so, they inadvertantly confirm the negative stereotypes they were worried about in the first place.The results highlight just how crucial it is for older adults, as well clinicians, to be aware of how ageist beliefs about older adults can affect older adults’ real memory test performance.”Older adults should be careful not to buy into negative stereotypes about aging — attributing every forgetful moment to getting older can actually worsen memory problems.” said Sarah Barber, a postdoctoral researcher at the USC Davis School and lead author of the study.However, there is a way to eliminate the problem, the study reveals: “No one had yet examined the intriuging possibility that the mechanisms of stereotype threat vary according to age,” Barber said.Barber and her co-author Mara Mather, professor of gerontology and psychology at USC, conducted two experiments in which adults from the ages of 59 to 79 completed a memory test. Some participants were first asked to read fake news articles about memory loss in older adults, and others did not. Notably, the researchers structured the test so that half of the participants earned a monetary reward for each word they remembered; the other half lost money for each word they forgot.In past tests, 70 percent of older adults met diagnostic criteria for dementia when examined under stereotype threat, compared to approximately 14 percent when not assessed under threat.But the latest research shows that stereotype threat can actually improve older adults’ performance on memory tests, under certain conditions.For participants who had something to gain, being confronted with age stereotypes meant poorer performance on memory tests. They scored about 20 percent worse than people who were not exposed to the stereotype.But when the test was framed in terms of preventing losses due to forgetting, the results flipped: participants reminded of the stereotypes about aging and memory loss actually scored better than those who were under no stereotype threat.”Stereotype threat is generally thought to be a bad thing, and it is well established that it can impair older adults’ memory performance. However, our experiments demonstrate that stereotype threat can actually enhance older adults’ memory if the task involves avoiding losses,” Barber said.Older adults, it seems, respond to stereotype threat by changing their motivational priorities and focusing more on avoiding mistakes. The study is part of a critical body of work on risk taking and decision making among older adults from the USC Davis School of Gerontology, named for AARP founder Leonard Davis and the leading research center in the world on aging and its biological, psychological, political and economic dimensions.”Our experiments suggest an easy intervention to eliminate the negative effects of stereotype threat on older adults — clinicians should simply change the test instructions to emphasize the importance of not making mistakes,” Barber said.The research was funded by the National Institutes of Health (grant numbers T32-AG00037, R01-AG025340, R01-AG038043 and K02-AG032309).

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Memory improves for older adults using computerized brain-fitness program

June 25, 2013 — UCLA researchers have found that older adults who regularly used a brain-fitness program on a computer demonstrated significantly improved memory and language skills.The UCLA team studied 69 dementia-free participants, with an average age of 82, who were recruited from retirement communities in Southern California. The participants played a computerized brain-fitness program called Dakim BrainFitness, which trains individuals through more than 400 exercises in the areas of short- and long-term memory, language, visual-spatial processing, reasoning and problem-solving, and calculation skills.The researchers found that of the 69 participants, the 52 individuals who over a six-month period completed at least 40 sessions (of 20 minutes each) on the program showed improvement in both immediate and delayed memory skills, as well as language skills.The findings suggest that older adults who participate in computerized brain training can improve their cognitive skills.The study’s findings add to a body of research exploring whether brain fitness tools may help improve language and memory and ultimately help protect individuals from the cognitive decline associated with aging and Alzheimer’s disease.Age-related memory decline affects approximately 40 percent of older adults. And while previous studies have shown that engaging in stimulating mental activities can help older adults improve their memory, little research had been done to determine whether the numerous computerized brain-fitness games and memory training programs on the market are effective in improving memory. This is one of the first studies to assess the cognitive effects of a computerized memory-training program.The study is published in the July issue of the American Journal of Geriatric Psychiatry.

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Making memories: Practical quantum computing moves closer to reality

June 19, 2013 — Researchers at the University of Sydney and Dartmouth College have developed a new way to design quantum memory, bringing quantum computers a step closer to reality. The results will appear June 19 in the journal Nature Communications.Quantum computing may revolutionize information processing, by providing a means to solve problems too complex for traditional computers, with applications in code breaking, materials science and physics. But figuring out how to engineer such a machine, including vital subsystems like quantum memory, remains elusive.In the worldwide drive to build a useful quantum computer, the simple-sounding task of effectively preserving quantum information in a quantum memory is a major challenge. The same physics that makes quantum computers potentially powerful also makes them likely to experience errors, even when quantum information is just being stored idly in memory. Keeping quantum information “alive” for long periods, while remaining accessible to the computer, is a key problem.The Sydney-Dartmouth team’s results demonstrate a path to what is considered a holy grail in the research community: storing quantum states with high fidelity for exceptionally long times, even hours according to their calculations. Today, most quantum states survive for tiny fractions of a second.”Our new approach allows us to simultaneously achieve very low error rates and very long storage times,” said co-senior author Dr. Michael J. Biercuk, director of the Quantum Control Laboratory in the University of Sydney’s School of Physics and ARC Centre for Engineered Quantum Systems. “But our work also addresses a vital practical issue — providing small access latencies, enabling on-demand retrieval with only a short time lag to extract stored information.”The team’s new method is based on techniques to build in error resilience at the level of the quantum memory hardware, said Dartmouth Physics Professor Lorenza Viola, a co-senior author who is leading the quantum control theory effort and the Quantum Information Initiative at Dartmouth.”We’ve now developed the quantum ‘firmware’ appropriate to control a practically useful quantum memory,” added Biercuk. “But vitally, we’ve shown that with our approach a user may guarantee that error never grows beyond a certain level even after very long times, so long as certain constraints are met. …

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Adolescents’ high-fat diet impairs memory and learning

June 17, 2013 — A high-fat diet in adolescence appears to have long-lasting effects on learning and memory during adulthood, a new study in mice finds. The results were presented Saturday at The Endocrine Society’s 95th Annual Meeting in San Francisco.Adolescent mice fed a normal-calorie but high-fat diet became moderately obese but not diabetic, and they displayed significantly impaired spatial memory, according to the study authors, from CEU-San Pablo University (Universidad CEU-San Pablo) in Madrid. Spatial memory allows recording of information needed to navigate in a familiar environment and is pivotal for learning, said the lead author, Mariano Ruiz-Gayo, PhD, a professor of pharmacology at the university.Adult mice that received the same diet had intact performance on memory tasks, showing that, unlike the adolescents, they were not sensitive to the effects of the fatty diet, he reported.”This study shows that normocaloric diets containing high amounts of saturated fat might have deleterious and long-lasting effects on the developing brain, even in the absence of apparent diabetes,” Ruiz-Gayo said.In their study, the investigators gave 15 male adolescent mice an eight-week, high-fat diet in which 45 percent of the calories came from unhealthy, saturated fat. Another 15 male mice received a conventional diet with the same number of calories (the control group). A similar study was carried out in adult mice so the researchers could test the effects of a high-fat diet starting later in life.To test the rodents’ spatial memory, the researchers used the novel location recognition test. In this test, the mice were placed in an open-field box — an open but walled box with a single chamber — containing two objects, plastic toy (Lego) pieces. The mice were already familiar with the box and one of the objects, but the other object was new to them. The mice explored the box for 10 minutes initially. One hour and 24 hours later, the mice returned to the box, where each time the new object was in a different position. The researchers recorded how long it took the rodents to find the new object.The scientists found that it took mice significantly longer to find the new object if they had received the high-fat diet when their brains were immature. …

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Memory-boosting chemical identified in mice: Cell biologists find molecule targets a key biological pathway

June 14, 2013 — Memory improved in mice injected with a small, drug-like molecule discovered by UCSF San Francisco researchers studying how cells respond to biological stress.The same biochemical pathway the molecule acts on might one day be targeted in humans to improve memory, according to the senior author of the study, Peter Walter, PhD, UCSF professor of biochemistry and biophysics and a Howard Hughes Investigator.The discovery of the molecule and the results of the subsequent memory tests in mice were published in eLife, an online scientific open-access journal, on May 28, 2013.In one memory test included in the study, normal mice were able to relocate a submerged platform about three times faster after receiving injections of the potent chemical than mice that received sham injections.The mice that received the chemical also better remembered cues associated with unpleasant stimuli — the sort of fear conditioning that could help a mouse avoid being preyed upon.Notably, the findings suggest that despite what would seem to be the importance of having the best biochemical mechanisms to maximize the power of memory, evolution does not seem to have provided them, Walter said.”It appears that the process of evolution has not optimized memory consolidation; otherwise I don’t think we could have improved upon it the way we did in our study with normal, healthy mice,” Walter said.The memory-boosting chemical was singled out from among 100,000 chemicals screened at the Small Molecule Discovery Center at UCSF for their potential to perturb a protective biochemical pathway within cells that is activated when cells are unable to keep up with the need to fold proteins into their working forms.However, UCSF postdoctoral fellow Carmela Sidrauski, PhD, discovered that the chemical acts within the cell beyond the biochemical pathway that activates this unfolded protein response, to more broadly impact what’s known as the integrated stress response. In this response, several biochemical pathways converge on a single molecular lynchpin, a protein called eIF2 alpha.Scientists have known that in organisms ranging in complexity from yeast to humans different kinds of cellular stress — a backlog of unfolded proteins, DNA-damaging UV light, a shortage of the amino acid building blocks needed to make protein, viral infection, iron deficiency — trigger different enzymes to act downstream to switch off eIF2 alpha.”Among other things, the inactivation of eIF2 alpha is a brake on memory consolidation,” Walter said, perhaps an evolutionary consequence of a cell or organism becoming better able to adapt in other ways.Turning off eIF2 alpha dials down production of most proteins, some of which may be needed for memory formation, Walter said. But eIF2 alpha inactivation also ramps up production of a few key proteins that help cells cope with stress.Study co-author Nahum Sonenberg, PhD, of McGill University previously linked memory and eIF2 alpha in genetic studies of mice, and his lab group also conducted the memory tests for the current study.The chemical identified by the UCSF researchers is called ISRIB, which stands for integrated stress response inhibitor. ISRIB counters the effects of eIF2 alpha inactivation inside cells, the researchers found.”ISRIB shows good pharmacokinetic properties [how a drug is absorbed, distributed and eliminated], readily crosses the blood-brain barrier, and exhibits no overt toxicity in mice, which makes it very useful for studies in mice,” Walter said. These properties also indicate that ISRIB might serve as a good starting point for human drug development, according to Walter.Walter said he is looking for scientists to collaborate with in new studies of cognition and memory in mouse models of neurodegenerative diseases and aging, using ISRIB or related molecules.In addition, chemicals such as ISRIB could play a role in fighting cancers, which take advantage of stress responses to fuel their own growth, Walter said. Walter already is exploring ways to manipulate the unfolded protein response to inhibit tumor growth, based on his earlier discoveries.At a more basic level, Walter said, he and other scientists can now use ISRIB to learn more about the role of the unfolded protein response and the integrated stress response in disease and normal physiology.Additional UCSF study authors are Diego Acosta-Alvear, PhD, Punitha Vedantham, PhD, Brian Hearn, PhD, Ciara Gallagher, PhD, Kenny Ang, PhD, Chris Wilson, PhD, Voytek Okreglak, PhD, Byron Hann, MD, PhD, Michelle Arkin, PhD, and Adam Renslo, PhD. Other authors are Han Li, PhD, and Avi Ashkenazi, PhD, from Genentech; and, Karim Nader, PhD, Karine Gamache, and Arkady Khoutorsky, PhD, from McGill University. The study was funded by the Howard Hughes Medical Institute.

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Mental block: Professor discovers way to alter memory

June 4, 2013 — A series of studies conducted by an Iowa State University research team shows that it is possible to manipulate an existing memory simply by suggesting new or different information. The key is timing and recall of that memory, said Jason Chan, an assistant professor of psychology at Iowa State.”If you reactivate a memory by retrieving it, that memory becomes susceptible to changes again. And if at that time you give people new contradictory information, that can make the original memory much harder to retrieve later,” Chan said.One of the major findings from the studies, published in the latest issue of Proceedings of the National Academy of Sciences, is the impact on declarative memory — a memory that can be consciously recalled and verbally described, such as what you did last weekend. The effects are powerful because people are retrieving memory and then incorporating new information. Chan and Jessica LaPaglia, a graduate student at Iowa State, tested the impact of new information when presented at different time intervals after the retrieval of the original memory.If it was immediate, the memory could be altered. However, there was no effect on the original memory when the information was presented 48 hours later. Chan said based on other studies, it appears there is a six-hour window before the memory is reconsolidated after recall and cannot be altered. Likewise, they found no effect if the information was presented in a different context than the original memory.”During that reconsolidation period, that’s when the memory is easy to be interfered with. Once that window closes and that memory is stable again, if you get new information it should not interfere with that original memory,” Chan said. “We found support for that idea in a number of experiments in which we varied the delay between the interfering memory or the misinformation and when people took that initial test.”Impact outside of an experimental settingFor the studies, participants watched a 40-minute episode of the TV show “24” in which a terrorist uses a hypodermic needle to attack a flight attendant. …

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