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by Simon Makin The first drug specifically designed to improve cognitive impairment in Down's syndrome is being tested in humans. David Nutt, former drug policy adviser to the UK government, told delegates at the Festival of Neuroscience in London yesterday that he is collaborating with pharmaceutical company Roche in trials of a substance it developed, called RG1662. RG1662 reverses the effects of a chemical messenger in the brain called GABA – a neurotransmitter that inhibits brain activity. The drug acts on a specific type of brain receptor found mostly in the hippocampus, a part of the brain involved in memory. It is thought that it will reduce excessive inhibition in the hippocampus, thought to underlie memory and learning problems commonly seen in people with Down's. The study is currently assessing safety and tolerability of the drug in 33 adults with Down's, but researchers will also measure motor skills, reaction time and memory, and compare the results with those of people taking a placebo. The aim is to find appropriate doses to use in a full clinical trial, which Nutt says should happen this year. Roche said in a statement that RG1662 may help people with Down's as it has "a unique pharmacology that enables the targeting of GABA over-activity mainly in brain systems important for cognition, learning and memory". © 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: 18026 - Posted: 04.13.2013

By GRETCHEN REYNOLDS Two new experiments, one involving people and the other animals, suggest that regular exercise can substantially improve memory, although different types of exercise seem to affect the brain quite differently. The news may offer consolation for the growing numbers of us who are entering age groups most at risk for cognitive decline. It was back in the 1990s that scientists at the Salk Institute for Biological Studies in La Jolla, Calif., first discovered that exercise bulks up the brain. In groundbreaking experiments, they showed that mice given access to running wheels produced far more cells in an area of the brain controlling memory creation than animals that didn’t run. The exercised animals then performed better on memory tests than their sedentary labmates. Since then, scientists have been working to understand precisely how, at a molecular level, exercise improves memory, as well as whether all types of exercise, including weight training, are beneficial. The new studies provide some additional and inspiring clarity on those issues, as well as, incidentally, on how you can get lab rats to weight train. For the human study, published in The Journal of Aging Research, scientists at the University of British Columbia recruited dozens of women ages 70 to 80 who had been found to have mild cognitive impairment, a condition that makes a person’s memory and thinking more muddled than would be expected at a given age. Mild cognitive impairment is also a recognized risk factor for increasing dementia. Seniors with the condition develop Alzheimer’s disease at much higher rates than those of the same age with sharper memories. Copyright 2013 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: 18015 - Posted: 04.10.2013

By Felicity Muth This move from my old site to the Scientific American network has also coincided with my own physical move from the UK to the USA to start some new research. Given this is the closing of a chapter of my life (or rather, my PhD thesis, which will now no doubt sit on a dusty shelf somewhere until a grad student picks it up in 10 years time to use as a door stop), I felt now might be an appropriate time to write a little bit about what I have been doing for the past three years. In the past I have only written about other people’s research, but given that I am now a few months beyond the shock (I will resist using the word ‘trauma’ here) of it ‘all being over’, I feel like it might be time now to share a bit of what I did over my PhD. In one of my first meetings with my PhD supervisor, she said to me, ‘The way that I see it, you can either spend three months reading the limited amount of literature in your subject area, or you can go to Africa and get some data for yourself.’ This may have been the point where I realised I had chosen a good topic to study. Not only did not having much ‘literature’ to read due to the dearth of previous work done on this topic mean that I could kid myself that I was an ‘expert’ in the field after a few weeks, it was also liberating to know that most experiments that I carried out would be finding out new things. So, even before moving my books into my new PhD office, I was on a plane to Botswana to collect data on the nest building behaviour of the Southern masked weaverbird. When I tell people that the aim of my research is to work out how birds learn how to build nests, I usually get one of two responses. The first is, ‘they don’t learn anything of course, nest building in birds is innate.’ The other response is ‘surely that’s been done already?’ But actually, both of these (perfectly reasonable) assumptions are incorrect. © 2013 Scientific American,

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 17939 - Posted: 03.23.2013

When the mind is at rest, the electrical signals by which brain cells communicate appear to travel in reverse, wiping out unimportant information in the process, but sensitizing the cells for future sensory learning, according to a study of rats conducted by researchers at the National Institutes of Health. The finding has implications not only for studies seeking to help people learn more efficiently, but also for attempts to understand and treat post-traumatic stress disorder — in which the mind has difficulty moving beyond a disturbing experience. During waking hours, electrical signals travel from dendrites — antenna-like projections at one end of the cell — through the cell body. From the cell body, they then travel the length of the axon, a single long projection at the other end of the cell. This electrical signal stimulates the release of chemicals at the end of the axon, which bind to dendrites on adjacent cells, stimulating these recipient cells to fire electrical signals, and so on. When groups of cells repeatedly fire in this way, the electrical signals increase in intensity. Dr. Bukalo and her team examined electrical signals that traveled in reverse?from the cell’s axon, to the cell body, and out its many dendrites. The reverse firing, depicted in this diagram, happens during sleep and at rest, appearing to reset the cell and priming it to learn new information. It was previously known that, during sleep, these impulses were reversed, arising from waves of electrical activity originating deep within the brain. In the current study, the researchers found that these reverse signals weakened circuits formed during waking hours, apparently so that unimportant information could be erased from the brain. But the reverse signals also appeared to prime the brain to relearn at least some of the forgotten information. If the animals encountered the same information upon awakening, the circuits re-formed much more rapidly than when they originally encountered the information.

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 10: Biological Rhythms and Sleep
Link ID: 17916 - Posted: 03.19.2013

Peter Fimrite Scientists at Stanford University have tapped into the mind of the mouse and are now circulating information about how the pesky rodents think. A team of Stanford researchers planted tiny probes inside the brains of mice to detect what were essentially mouse memories, according to a study published last month in the online edition of Nature Neuroscience. The experiment involved the insertion of a needlelike microscope into the hippocampus - a part of the brain associated with spatial and episodic memory. The microscope detected cellular activity and broadcast digital images through a cell phone camera sensor that fit like a hat over the heads of the critters as they scampered around an enclosure. "We're not really reading their minds," said the lead researcher, Mark Schnitzer, who is an associate professor of biology and applied physics at Stanford. "What is the mind of a mouse, anyway? I don't know. What we're doing is reading a spatial map in the brain. It is one little component of many, many processes that are going on inside." Over the course of a month, the scientists were able to document patterns of activity in some 700 neurons and pinpoint areas of the brain where mice store long-term information. It is important, Schnitzer said, because long-term memory is an area of the brain that researchers are struggling to understand as they attempt to develop new therapies for neurodegenerative diseases, including Alzheimer's disease. "Those are clearly diseases in which information storage has been impaired," Schnitzer said. "Now that we can look at the neural code for how the spatial information is stored, it opens the door directly to subsequent experiments. That's the logical next step." © 2013 Hearst Communications Inc.

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 17908 - Posted: 03.18.2013

By Christie Aschwanden, A lawyer contacted Beatrice Golomb, a physician at the VA San Diego Healthcare Center, because he could no longer follow a normal conversation with his clients. A radiologist told Golomb that he found himself suddenly unable to distinguish left from right. A third person told her he had grown so forgetful that his doctor assumed he had Alzheimer’s. All three had developed their memory problems after taking a cholesterol-lowering statin drug, and the symptoms improved after they stopped the medication. The statin revolution began in 1987, when lovastatin was approved by the Food and Drug Administration. Since then, this class of drugs has transformed cardiac medicine, says Allen Taylor, chief of cardiology at MedStar Georgetown University Hospital. “Cardiovascular disease affects one in two people. This is the one drug that works.” But these drugs are not without risks. Golomb has amassed thousands of reports at her Web site Statineffects.com, detailing adverse reactions from statins. She says that cognitive problems are the second-most-common side effect reported in her database, after muscle pain. In a 2009 report in the journal Pharmacotherapy, Golomb described 171 patients who’d reported cognitive problems after taking statins. The idea that a cholesterol-lowering drug could make your brain fuzzy might sound crazy, and Golomb says the notion was greeted with suspicion at first. But eventually the FDA received enough such reports that last February it ordered drug companies to add a new warning label about possible memory problems. © 1996-2013 The Washington Post

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 17905 - Posted: 03.15.2013

By Deborah Kotz, Globe Staff No doubt, the biggest appeal of exercise is to build biceps, heart muscle, and perhaps some definition in those abdominal muscles, but how about using exercise to build your brain? It’s been known for some time that exercise can lift your mood, ward off depression, and help the brain age more gracefully -- free of memory loss and dementia. But now researchers have found that even just one bout of exercise can -- even better than a cup of coffee -- improve your mental focus and cognitive performance for any challenging task you face that day. A new analysis of 19 studies involving 586 kids, teens, and young adults that was published Wednesday in the British Medical Journal found that short 10 to 40 minutes bursts of exercise led to an immediate boost in concentration and mental focus, likely by improving blood flow to the brain. “These results provide further evidence that doing about 20 minutes of exercise just before taking a test or giving a speech can improve performance,” said Harvard psychiatrist Dr. John Ratey, who wrote the best-selling book Spark: The Revolutionary New Science of Exercise and the Brain. Another piece of proof can be seen in the brain scan above -- from a 2009 University of Illinois study also included in the new analysis -- which compares the brain activity of 9-year-olds who took a brisk walk and those who didn’t take a walk. The walkers had far more activity in brain regions involved with focused attention and filtering out noisy distractions while they were taking a challenging test compared to the non-walkers. © 2013 NY Times Co.

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: 17881 - Posted: 03.09.2013

by Andy Coghlan Stimulating the brain with electrical signals can sharpen some of your faculties, but now it seems it can dim others at the same time. Transcranial electrical stimulation (TES), delivered by electrodes on the surface of the head, has been shown to double people's speed of learning. Now the first evidence has emerged that improvements in one aspect of learning might come at the expense of other abilities. Roi Cohen Kadosh of the University of Oxford, showed volunteers pairs of unfamiliar symbols. Each symbol had a secret numerical value, and the volunteers' task was to state – as quickly as possible while avoiding mistakes – which symbol in a pair had the bigger value. The correct answer was then displayed. Over six sessions in one week, it was possible to measure how quickly and efficiently the volunteers learned the value of each symbol. Second task In a second task, participants had to register which of each pair of symbols was physically larger, a measure of automatic thinking. "Automaticity is the skill of doing things without thinking about them, such as reading, driving or mounting stairs," says Cohen Kadosh, who conducted the experiment with Teresa Iucalano of the Stanford Cognitive and Systems Neuroscience Laboratory in Palo Alto, California. During the experiments, volunteers received TES to their posterior parietal cortex – vital for numerical learning – or their dorsolateral prefrontal cortex – vital for automaticity. Some unknowingly received a sham treatment. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 17877 - Posted: 03.09.2013

Daphne Bavelier & Richard J. Davidson Video games are associated with a variety of negative outcomes, such as obesity, aggressiveness, antisocial behaviour and, in extreme cases, addiction2. At the same time, evidence is mounting that playing games can have beneficial effects on the brain. After spending an hour a day, 5 days a week for 8–10 weeks spotting snipers and evading opponents in shooter games such as Call of Duty or Unreal Tournament, young adults saw more small visual details in the middle of clutter and more accurately distinguished between various shades of grey3. After 10 hours stretched over 2 weeks spent chasing bad guys in mazes and labyrinths, players were better able to rotate an image mentally4, an improvement that was still present six months later and could be useful for activities as varied as navigation, research chemistry and architectural design. After guiding small rodents to a safe exit amid obstacles during a version of the game Lemmings that was designed to encourage positive behaviour, players were more likely in simulated scenarios to help another person after a mishap or to intervene when someone was being harassed5. Because gaming is clearly here to stay, some scientists are asking how to channel people's love of screen time towards positive effects on the brain and behaviour by designing video games specifically intended to train particular aspects of behaviour and brain function. One game, for example, aims to treat depression by introducing cognitive behavioural therapy while users fight off negative thoughts in a fantasy world6. In Re-mission, young cancer patients blast cancer cells and fight infections and the side effects of therapy — all to encourage them to stick with treatment (see www.re-mission.net). © 2013 Nature Publishing Group

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 17859 - Posted: 03.02.2013

By Steven Ross Pomeroy Everyone enjoys the occasional practical joke – assuming the gag isn’t mean-spirited or overly perilous, even the prank’s poor victim can appreciate the punch line! I’m sure you have your favorites: gluing dollars to sidewalks, filling your co-worker’s office with balloons, moving your roommate’s bed to the basement… while he’s sleeping in it. More typical stunts may employ whoopee cushions, fake vomit, and hand buzzers, but honestly, those are a tad sophomoric and overdone. Thus, in an effort to elevate the standard of stunts, I’d like to present a gag that makes use not of stink bombs, but of science. How to implant false memories in your friends, in four steps: In The Demon-Haunted World, Carl Sagan argued that implanting false memories in people is not only possible, but is actually pretty easy when attempted in the proper settings with a gullible subject, He cited as examples people who, at the urging of therapists or hypnotists, genuinely start to believe that they’d been abducted by UFOs or falsely remember being abused as a child. For these people, the distinction between memory and imagination becomes blurred, and events that never actually took place become sewn into their memories as real events. They can even describe these false remembrances incredibly vividly – as if they actually happened! “Memory can be contaminated,” Sagan wrote. “False memories can be implanted even in minds that do not consider themselves vulnerable and uncritical.” © 2013 Scientific American

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 17827 - Posted: 02.20.2013

By Laura Sanders An element of surprise may be the key to whitewashing a painful memory. People who encountered something unexpected were better able to shake a troubling association, a new laboratory study finds. The results, published in the Feb. 15 Science, bring scientists closer to being able to weaken traumatic memories with help from a drug. Understanding how the brain forms and reforms traumatic memories might lead to treatments that would help people who suffer from post-traumatic stress disorder and other anxiety disorders. “The idea that an original memory could have the sting taken out of it — that’s been very appealing,” says psychiatrist Roger Pitman of Harvard Medical School and Massachusetts General Hospital, who was not involved in the research. Memories are not written in neural stone. Recent results in animals and humans have shown that once called to mind, painful memories’ emotional edges can be blunted. Experiments have used certain drugs to weaken associations between a memory and a negative response. But the details of how and why those drugs work haven’t been clear. The new result may have uncovered a previously underappreciated step in that weakening process: In order for the emotional response tied to a memory to wither, something unexpected must happen while the person is recalling the memory. This mismatch between what a person expects and what actually happens — called a prediction error — puts a memory into a wobbly, vulnerable form that can be washed out, says study coauthor Merel Kindt of the University of Amsterdam. © Society for Science & the Public 2000 - 2013

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: 17810 - Posted: 02.16.2013

By Erin Wayman Photographer Bill Wallauer was following a group of chimpanzees in Tanzania’s Gombe Stream National Park one March day when a young female caught his eye. She had climbed a tree, inserted a thin, peeled branch into a hole and was fishing out carpenter ants. Wallauer, of the Jane Goodall Institute, took out his video camera and filmed the chimp as she slurped up insects for several minutes. What Wallauer witnessed wasn’t supposed to happen. Though chimps in other areas use tools to collect carpenter ants, scientists studying the Kasekela chimp community at Gombe had rarely seen the behavior since Jane Goodall began her fieldwork there in 1960. Before Wallauer’s 1994 observation, researchers had seen only one other instance of the behavior, in 1978. This type of tool use was considered a fluke. But when Robert O’Malley, a primatologist now at Kenyon College in Gambier, Ohio, went to Gombe in the late 2000s, he noticed many of the Kasekela chimps regularly fishing for ants. He wondered why, after decades with only a couple of sporadic sightings, ant probing had become a widespread habit. Because of meticulous record keeping at Gombe, O’Malley and his colleagues had a rare opportunity to reconstruct the origin of this behavior. An adult female immigrant who joined the Kasekela group in the early 1990s, the team concluded, introduced ant fishing, a common practice in her previous community. The finding, reported late last year in Current Anthropology, marks the first time in the more than 50-year history of chimp field studies that anyone has documented the transfer of a cultural tradition from one wild chimp group to another. © Society for Science & the Public 2000 - 2013

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: 17720 - Posted: 01.28.2013

By DOUGLAS QUENQUA Learning becomes more difficult as we age not because we have trouble absorbing new information, but because we fail to forget the old stuff, researchers say. Mice whose brains were genetically modified to resemble those of adult humans showed no decrease in the ability to make the strong synaptic connections that enable learning — a surprise to neuroscientists at the Medical College of Georgia at Georgia Regents University, whose findings appear in the journal Scientific Reports. Yet as the modified mice entered adulthood, they were less capable of weakening connections that already existed, and that made it hard for them to form robust new long-term memories. Think of it as writing on a blank piece of white paper versus a newspaper page, said the lead author, Joe Z. Tsien. “The difference is not how dark the pen is,” he said, “but that the newspaper already has writing on it.” The researchers focused on two proteins — NR2A and NR2B — long known to play a role in the forging of new connections in the brain. Before puberty, the brain produces more NR2B than NR2A; in adulthood, the ratio reverses. By prodding mice to produce more NR2A than NR2B, effectively mimicking the postpubescent brain, scientists expected the subjects to have trouble forming strong connections. Instead, the mice showed no trouble creating new short-term memories, but brain scans showed that they struggled to weaken the connections that had formed older long-term memories. © 2013 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: 17701 - Posted: 01.22.2013

Ed Yong For years, a particular protein has been cast as a lynchpin of long-term memory. Inhibiting this enzyme could erase old memories, whereas adding it could strengthen faded ones1–3. But two independent groups of US scientists have now seriously challenged the role of this 'memory molecule' by developing mice that completely lack it — and showing that these mice have no detectable memory problems. Their results are published today in Nature4, 5. The excitement around the enzyme, called protein kinase M-ζ (PKM-ζ), started building in 2006, when Todd Sacktor at the SUNY Downstate Medical Center in New York City wiped out established spatial memories in rats. He did so by injecting their brains with ZIP, a small peptide that is meant to block the enzyme1. Other teams obtained similar results, erasing different types of memory by injecting ZIP into various brain regions in rodents, flies and sea slugs. And in 2011, Sacktor did the opposite: he strengthened rats' memory of unpleasant tastes by injecting their brains with viruses carrying extra copies of PKM-ζ3. These fascinating studies suggested that long-term memory, rather than being static and stable, is surprisingly fragile, and depends on the continuous activity of a single enzyme. Richard Huganir of Johns Hopkins University in Baltimore, Maryland, was intrigued by these results, but was concerned that much of the data depended on the actions of ZIP. He and his collaborators took a different route, by deleting two genes — one for PKM-ζ and one for a related protein called PKC-ζ — in embryonic mice4. Working independently, Robert Messing and colleagues at the University of California, San Francisco, created similar mice5. © 2013 Nature Publishing Group

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 17653 - Posted: 01.05.2013

Barry Gordon The intuitive notion of a “photographic” memory is that it is just like a photograph: you can retrieve it from your memory at will and examine it in detail, zooming in on different parts. But a true photographic memory in this sense has never been proved to exist. Most of us do have a kind of photographic memory, in that most people's memory for visual material is much better and more detailed than our recall of most other kinds of material. For instance, most of us remember a face much more easily than the name associated with that face. But this isn't really a photographic memory; it just shows us the normal difference between types of memory. Even visual memories that seem to approach the photographic ideal are far from truly photographic. These memories seem to result from a combination of innate abilities, combined with zealous study and familiarity with the material, such as the Bible or fine art. Sorry to disappoint further, but even an amazing memory in one domain, such as vision, is not a guarantee of great memory across the board. That must be rare, if it occurs at all. A winner of the memory Olympics, for instance, still had to keep sticky notes on the refrigerator to remember what she had to do during the day. So how does an exceptional, perhaps photographic, memory come to be? It depends on a slew of factors, including our genetics, brain development and experiences. It is difficult to disentangle memory abilities that appear early from those cultivated through interest and training. Most people who have exhibited truly extraordinary memories in some domain have seemed to possess them all their lives and honed them further through practice. © 2012 Scientific American

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 17645 - Posted: 01.01.2013

By Jason G. Goldman While second nature to many of us, driving a car is actually a fairly complex process. At its most stripped down version, first you sit in the driver’s seat, then you start the engine, then you shift into gear, and then you must simultaneously steer while keeping your foot on the gas pedal. That doesn’t include things like adjusting your mirrors, verifying that you won’t drive into another person or car, and so on. In one sense, it is incredibly impressive that three dogs in New Zealand have learned – in a fairly rudimentary way – to drive a car. They sit in the driver’s seat, shift into gear, operate the steering wheel, and step on the accelerator. Those deserving the true accolades however are not the dogs, but the human trainers for their impressive patience and determination. The training that led man’s best friend to operate a car is no different from the kind of training behind the bird shows found at zoos all over the world, or the dolphin, killer whale, seal, or sea lion displays you might see at Sea World. It’s the same kind of training that scientists use to probe the emotional and cognitive lives of rats, mice, and the other critters that populate their laboratories. At the end of the day, it all comes down to a form of learning first described by Edward L. Thorndike at the beginning of the 1900s, which was later expanded and popularized by B.F. Skinner and taught to every student of Introductory Psychology: operant conditioning. While classical conditioning is a form of learning that binds external stimuli to reflexive, involuntary responses, operant conditioning involves voluntary behaviors, and is maintained over time by the consequences that follow those behaviors. In one experiment, Skinner placed pigeons individually into experimental chambers (sometimes referred to as “Skinner boxes”) that were designed to deliver food rewards at systematic intervals. He found that by rewarding a bird after it displayed a desired behavior, he could motivate the bird to increase the frequency of that particular behavior. © 2012 Scientific American

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 17607 - Posted: 12.14.2012

By Brian Mossop Ten years into serving a life sentence for the rape of Jennifer Thompson, Ronald Cotton stepped out of prison a free man. It took that long for DNA evidence to exonerate Cotton, refuting a weak case built mostly on eyewitness accounts. According to Simon's new book In Doubt, despite advances in DNA forensic technologies, eyewitness testimony remains the most common way to nab criminals in the Anglo-American justice system. The problem, however, is that our mind often subconsciously twists the evidence to coincide with our biases, and we end up incarcerating innocent people. Simon, a professor of law and psychology at the University of Southern California, says that the false conviction rate, based on exoneration data from capital murder cases, is estimated to be near 5 percent, although that figure represents only a fraction of those wrongly imprisoned. Eyewitness testimony boils down to how well the witness remembers the event. Studies have shown that a victim of a crime may remember a specific piece of information from the horrid event, such as the attacker's jacket or a strange smell, but fail to recall other details. Investigators are left with a weak profile of the perpetrator. In Cotton's case, the victim initially chose two men from the lineup, and only after repeated questioning from investigators could Thompson say Cotton was her assailant. © 2012 Scientific American

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 17564 - Posted: 12.03.2012

By Hal Arkowitz and Scott O. Lilienfeld When Mick Jagger first sang “What a drag it is getting old,” he was 23 years old. Now at 69, he is still a veritable Jumpin' Jack Flash on stage. Jagger seems to have found the secret to staying physically fit in his advancing years, but getting old can be a drag on the psyche. Many older adults fear memory loss and worry they are headed down the road to dementia, such as Alzheimer's disease. Every time they forget their keys, leave a door unlocked or fail to remember a name, they are reminded of this nagging concern. In most cases, however, such annoying incidents are part of normal age-related memory loss, not a sign of impending dementia. Although lots of older adults think such a decline is inevitable, there is good news for many of them. Researchers have developed an array of helpful methods and activities that exercise our minds and bodies that can help keep the older mind in relatively good condition. In this column, we examine the most promising ways to shore up memory in the normal aging brain. Memory is not a single entity. The term encompasses several types of remembering, not all of which decline with age. For instance, older people still retain their vocabulary, along with general knowledge about the world (semantic memory). They can also perform certain routine tasks, such as making an omelet or typing on a computer (procedural memory), about as well as they could when they were younger. People do become worse, however, at recalling recent events in their lives (episodic memory) or where they first learned a piece of information (source memory), managing the temporary storage of short-term information (working memory), and remembering to do things in the future (prospective memory). © 2012 Scientific American

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: 17491 - Posted: 11.14.2012

Seniors who take common medications to treat insomnia, anxiety, itching or allergies may have symptoms of forgetfulness or trouble concentrating, a new review concludes. About 90 per cent of people aged 65 and older take at least one prescription medication and almost half take five or more, studies suggest. About 90 per cent of people aged 65 and older take at least one prescription medication, U.S. research suggests.About 90 per cent of people aged 65 and older take at least one prescription medication, U.S. research suggests. (iStock) As people increasingly report memory and attention problems and seek testing for early dementia, researchers in Montreal wanted to see how medications can induce such symptoms. Dr. Cara Tannenbaum, research chair at the Montreal Geriatric University Institute and her co-authors in Montreal, Calgary, Australia and the U.S. reviewed 162 studies on medications most likely to affect memory, creating what's called an amnesia effect, or affect brain functions like attention and concentration that are called non-amnestic. "There is a consistent body of evidence suggesting that drug-induced mild cognitive impairment can occur with episodic use of medications for insomnia, anxiety, [itching] or allergy symptoms," the study's authors concluded in the journal Drugs & Aging. "Combined amnestic and non-amnestic deficits occur with the use of benzodiazepine agents and may partially underlie older adults' frequent complaints of forgetfulness or difficulty concentrating." © CBC 2012

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 17465 - Posted: 11.07.2012

The brain holds in mind what has just been seen by synchronizing brain waves in a working memory circuit, an animal study supported by the National Institutes of Health suggests. The more in-sync such electrical signals of neurons were in two key hubs of the circuit, the more those cells held the short-term memory of a just-seen object. Charles Gray, Ph.D., of Montana State University, Bozeman, and colleagues, report their findings Nov. 1, 2012, online, in the journal Science Express. "This work demonstrates, for the first time, that there is information about short term memories reflected in in-sync brainwaves," explained Gray. "The Holy Grail of neuroscience has been to understand how and where information is encoded in the brain. This study provides more evidence that large scale electrical oscillations across distant brain regions may carry information for visual memories," said NIMH director Thomas R. Insel, M.D. Prior to the study, scientists had observed synchronous patterns of electrical activity between the two circuit hubs after a monkey saw an object, but weren’t sure if the signals actually represent such short-term visual memories in the brain. Rather, it was thought that such neural oscillations might play the role of a traffic cop, directing information along brain highways. To find out more, Gray, Rodrigo Salazar Ph.D., and Nick Dotson of Montana State and Steven Bressler, Ph.D., at Florida Atlantic University, Boca Raton, recorded electrical signals from groups of neurons in both hubs of two monkeys performing a visual working memory task. To earn a reward, the monkeys had to remember an object — or its location — that they saw momentarily on a computer screen and correctly match it. The researchers expected to see the telltale boost in synchrony during a delay period immediately after an object disappeared from the screen, when the monkey had to hold information briefly in mind.

Related chapters from BP7e: Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 17456 - Posted: 11.06.2012