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"Researchers led by New York University neuroscientist Joseph LeDoux recently claimed to be the first scientists to erase a single memory. Working with rats, LeDoux's team first taught the animals to fear both a beep and a siren by giving them an electric shock every time either of the tones sounded. Then LeDoux gave half the rats the drug U0126, which is known to interfere with memory storage, and replayed the beep without electric shocks. A day later, when LeDoux played back both tones to the rats, the animals that hadn't been given the drug were still fearful of both sounds. But the rats that had been given the memory-blocking drug weren't afraid of the beep, which they had last heard while under the influence of U0126. advertisement | article continues below Click here! Exactly how U0126 exerts its amnesiac effect is unknown, but it may block the synthesis of proteins that help strengthen connections between neurons and establish memories. The opportunity for erasure occurs during the act of retrieving a memory because that's when the memory is being updated and stabilized again for long-term storage. "Only those memories that are activated are vulnerable," LeDoux says. Drugs like U0126 may someday help sufferers of traumatic memories. A small group of human studies have been done on a drug called propranolol, which blocks the action of stress neurotransmitters that help cement memories in the brain, but LeDoux's work shows the potential for greater precision. "You might be able to reduce the traumatic impact of memories in people with PTSD," says LeDoux. "The good news is you wouldn't be erasing their memory bank." "

"Humans are storytelling machines. We don't passively perceive the world - we tell stories about it, translating the helter-skelter of events into tidy narratives. This is often a helpful habit, helping us make sense of mistakes, consider counterfactuals and extract a sense of meaning from the randomness of life. But our love of stories comes with a serious side-effect: like all good narrators, we tend to forsake the facts when they interfere with the plot. We're so addicted to the anecdote that we let the truth slip away until, eventually, those stories we tell again and again become exercises in pure fiction. Just the other day I learned that one of my cherished childhood tales - the time my older brother put hot peppers in my Chinese food while I was in the bathroom, thus scorching my young tongue - actually happened to my little sister. I'd stolen her trauma. The reason we're such consummate bullshitters is simple: we bullshit for each other. We tweak our stories so that they become better stories. We bend the facts so that the facts appeal to the group. Because we are social animals, our memory of the past is constantly being revised to fit social pressures. The power of this phenomenon was demonstrated in a new Science paper by Micah Edelson, Tali Sharot, Raymond Dolan and Yadin Dudai. The neuroscientists were interested in how the opinion of other people can alter our personal memories, even over a relatively short period of time. The experiment itself was straightforward. A few dozen people watched an eyewitness style documentary about a police arrest in groups of five. Three days later, the subjects returned to the lab and completed a memory test about the documentary. Four days after that, they were brought back once again and asked a variety of questions about the short movie while inside a brain scanner. This time, though, the subjects were given a "lifeline": they were shown the answers given by other people in their film-viewing g

"Virtually nobody has memories from very early childhood - but it's not because we don't retain information as young children. Rather, it may be because at that age, our brains don't yet function in a way that bundles information into the complex neural patterns that we know as memories. It's clear that young children do remember facts in the moment - such as who their parents are, or that one must say "please" before mom will give you candy. This is called "semantic memory." Until sometime between the ages two and four, however, children lack "episodic memory" -- memory regarding the details of a specific event. Such memories are stored in several parts of the brain's surface, or "cortex." For example, memory of sound is processed in the auditory cortexes, on the sides of the brain, while visual memory is managed by the visual cortex, at the back. A region of the brain called the hippocampus ties all the scattered pieces together. "

"MIT researchers have shown, for the first time ever, that memories are stored in specific brain cells. By triggering a small cluster of neurons, the researchers were able to force the subject to recall a specific memory. By removing these neurons, the subject would lose that memory. As you can imagine, the trick here is activating individual neurons, which are incredibly small and not really the kind of thing you can attach electrodes to. To do this, the researchers used optogenetics, a bleeding edge sphere of science that involves the genetic manipulation of cells so that they're sensitive to light. These modified cells are then triggered using lasers; you drill a hole through the subject's skull and point the laser at a small cluster of neurons. Now, just to temper your excitement, we should note that MIT's subjects in this case are mice - but it's very, very likely that the human brain functions in the same way. To perform this experiment, though, MIT had to breed genetically engineered mice with optogenetic neurons - and we're a long, long way off breeding humans with optogenetic brains. In the experiment, MIT gave mice an electric shock to create a fear memory in the hippocampus region of the brain (pictured above) - and then later, using laser light, activated the neurons where the memory was stored. The mice "quickly entered a defensive, immobile crouch," strongly suggesting the fear memory was being recalled."

"Jeffrey Mitchell, a volunteer firefighter in the suburbs of Baltimore, came across the accident by chance: A car had smashed into a pickup truck loaded with metal pipes. Mitchell tried to help, but he saw at once that he was too late. The car had rear-ended the truck at high speed, sending a pipe through the windshield and into the chest of the passenger-a young bride returning home from her wedding. There was blood everywhere, staining her white dress crimson. Mitchell couldn't get the dead woman out of his mind; the tableau was stuck before his eyes. He tried to tough it out, but after months of suffering, he couldn't take it anymore. He finally told his brother, a fellow firefighter, about it. Miraculously, that worked. No more trauma; Mitchell felt free. This dramatic recovery, along with the experiences of fellow first responders, led Mitchell to do some research into recovery from trauma. He eventually concluded that he had stumbled upon a powerful treatment. In 1983, nearly a decade after the car accident, Mitchell wrote an influential paper in the Journal of Emergency Medical Services that transformed his experience into a seven-step practice, which he called critical incident stress debriefing, or CISD. The central idea: People who survive a painful event should express their feelings soon after so the memory isn't "sealed over" and repressed, which could lead to post-traumatic stress disorder. In recent years, CISD has become exceedingly popular, used by the US Department of Defense, the Federal Emergency Management Agency, the Israeli army, the United Nations, and the American Red Cross. Each year, more than 30,000 people are trained in the technique. (After the September 11 attacks, 2,000 facilitators descended on New York City.) Even though PTSD is triggered by a stressful incident, it is really a disease of memory. The problem isn't the trauma-it's that the trauma can't be forgotten. Most memories, and their associated emotion

"Scientists say they have found a way to activate the brain cells that trigger particular memories, according to research published today in the journal Science. Researchers at MIT employed optogenetics, a branch of science that uses light to stimulate molecules, to show that memories reside in specific brain cells, and that activating a tiny fraction of brain cells can revive the entire memory. The study was performed on mice, but the researchers say it is a powerful demonstration that memories are tangible and are physically stored in a particular part of the brain. "We demonstrate that behaviour based on high-level cognition, such as the expression of a specific memory, can be generated in a mammal by highly specific physical activation of a specific small subpopulation of brain cells, in this case by light," said Susumu Tonegawa, the Picower Professor of Biology and Neuroscience at MIT and lead author of the study. In the early 1900s, the Canadian neurosurgeon Wilder Penfield found that when he electrically stimulated certain neurons in the hippocampus area of the brain, his patients vividly recalled whole events. Until now, however, scientists have been unable to prove that the direct reactivation of the hippocampus was enough to cause memory recall."

"Despite memory's obvious benefits, it can also let us down, said Daniel Schacter, PhD, longtime memory researcher and chair of Harvard University's psychology department, at an APA 2003 Annual Convention session honoring the publication of his book, "The Seven Sins of Memory: How the Mind Forgets and Remembers" (Houghton Mifflin, 2001). "Memory, for all that it does for us every day...for all the feats that can sometimes amaze us, can also be a troublemaker," said Schacter of his book, which describes the seven major categories of memory foibles being investigated by psychologists. However, noted Schacter, the same brain mechanisms account for memory's sins as well as its strengths, so investigating its negatives exposes its positives. "We shouldn't think of these fundamentally as flaws in the architecture of memory," he explained, "but rather as costs we pay for benefits in memory that make it work as well as it does most of the time." At the session, during which Schacter received the APA Div. 1 (Society for General Psychology) William James Book Award, he defined his book's seven sins. The first three are "sins of omission" that involve forgetting, and the second four are "sins of commission" that involve distorted or unwanted recollections."

"You'll probably remember exactly where you were and what you were doing when you first learned that passenger jets had crashed into the World Trade Center. People tend to form exceptionally vivid memories of highly consequential news, and it doesn't get much bigger than 9/11. Recollections of that day have given researchers a unique window into how the brain forms memories of shocking events. "It's as if a flashbulb goes off and you take a mental picture of your surroundings," says psychologist William Hirst of the New York School for Social Research. Flashbulb memories, as they are known, are tricky to study as people are seldom keen to talk to researchers just after hearing or seeing emotionally charged news. It can also be difficult to know how accurate a person's memory of the event is, since there is usually no way to be sure what actually happened. Elizabeth Phelps of New York University was in Manhattan on 9/11 and saw the attack. When fellow neuroscientist John Gabrieli called to check on her they "decided to put together a consortium of memory researchers, and started collecting data within a week"."

"Witness testimony has been the gold standard of the criminal justice system, revered in courtrooms and crime dramas as the evidence that clinches a case. Yet scientists have long cautioned that the brain is not a filing cabinet, storing memories in a way that they can be pulled out, consulted and returned intact. Memory is not so much a record of the past as a rough sketch that can be modified even by the simple act of telling the story. For scientists, memory has been on trial for decades, and courts and public opinion are only now catching up with the verdict. It has come as little surprise to researchers that about 75 percent of DNA-based exonerations have come in cases where witnesses got it wrong. This month, the Supreme Court heard its first oral arguments in more than three decades that question the validity of using witness testimony, in a case involving a New Hampshire man convicted of theft, accused by a woman who saw him from a distance in the dead of night. And in August the New Jersey Supreme Court set new rules to cope with failings in witness accounts, during an appeal by a man picked from a photo lineup, and convicted of manslaughter and weapons possession in a 2003 fatal shooting. Rather than the centerpiece of prosecution, witness testimony should be viewed more like trace evidence, scientists say, with the same fragility and vulnerability to contamination. Why is a witness's account so often unreliable? Partly because the brain does not have a knack for retaining many specifics and is highly susceptible to suggestion. "Memory is weak in eyewitness situations because it's overloaded," said Barbara Tversky, a psychology professor at Columbia University's Teachers College in New York. "An event happens so fast, and when the police question you, you probably weren't concentrating on the details they're asking about." "

"Scientists have for the first time recorded individual brain cells in the act of summoning a spontaneous memory, revealing not only where a remembered experience is registered but also, in part, how the brain is able to recreate it. The recordings, taken from the brains of epilepsy patients being prepared for surgery, demonstrate that these spontaneous memories reside in some of the same neurons that fired most furiously when the recalled event had been experienced. Researchers had long theorized as much but until now had only indirect evidence. Experts said the study had all but closed the case: For the brain, remembering is a lot like doing (at least in the short term, as the research says nothing about more distant memories). The experiment, being reported Friday in the journal Science, is likely to open a new avenue in the investigation of Alzheimer's disease and other forms of dementia, some experts said, as well as help explain how some memories seemingly come out of nowhere. The researchers were even able to identify specific memories in subjects a second or two before the people themselves reported having them. "This is what I would call a foundational finding," said Michael J. Kahana, a professor of psychology at the University of Pennsylvania, who was not involved in the research. "I cannot think of any recent study that's comparable. "

"A 54-year-old woman showed up in the emergency room at Georgetown University Hospital with her husband, unable to remember the past 24 hours. Her newer memories were hazy, too. One thing she did recall: Her amnesia had started right after having sex with her husband just an hour before. While sex can be forgettable or mind-blowing, for some people, it can quite literally be both at the same time. The woman, whose case was reported in the September issue of The Journal of Emergency Medicine, was experiencing transient global amnesia, a rare condition in which memory suddenly, temporarily, disappears. People with transient global amnesia suffer no side effects, and the memory problems usually reverse themselves in the span of a few hours. It's a rare condition, affecting only about 3 to 5 people per 100,000 each year. But what makes transient global amnesia so eerie is that researchers aren't sure what causes it, or why patients remain otherwise chatty and alert while missing large chunks of their memories."

"Stress in the Brain Anxiety has become a hot topic in education research, as educators and policymakers become increasingly focused on test performance and more-intensive curricula, and neuroscience has begun to provide a window into how the brain responds to anxiety. Anxieties and Stereotypes Researchers have found that the more anxious their female teachers were about math, the more likely girls-but not boys- were to endorse gender-related stereotypes about math ability. In turn, the girls who echoed those stereotypical beliefs were performing less well than other students in math by year's end. SOURCE: University of Chicago Anxiety can literally cut off the working memory needed to learn and solve problems, according to Dr. Judy Willis, a Santa Barbara, Calif.-based neurologist, former middle school teacher, and author of the 2010 book Learning to Love Math. When first taking in a problem, a student processes information through the amygdala, the brain's emotional center, which then prioritizes information going to the prefrontal cortex, the part responsible for the brain's working memory and critical thinking. During stress, there is more activity in the amygdala than the prefrontal cortex; even as minor a stressor as seeing a frowning face before answering a question can decrease a student's ability to remember and respond accurately. "When engaged in mathematical problem-solving, highly math-anxious individuals suffer from intrusive thoughts and ruminations," said Daniel Ansari, the principal investigator for the Numerical Cognition Laboratory at the University of Western Ontario, in London, Ontario. "This takes up some of their processing and working memory. It's very much as though individuals with math anxiety use up the brainpower they need for the problem" on worrying. Moreover, a series of experiments at the Mangels Lab of Cognitive Neuroscience of Memory and Attention at Baruch College at the City University of New York sugg

"Recall a time you said or did something incorrect in front of peers or authority figures. Now think of all the details you can recall associated with that experience. Where you were, who was there, any other things you wouldn't ordinarily remember about distant events such as what you wore, saw, did earlier or later that day. If you have a minute, write down some of these ancillary sensory memories. What you recall now is the result of your dopamine-reward network and your flashbulb memory or event memory system. As the brain evolved for survival of the animal and the species, much of what we humans now do is directed by hard-wired neural networks and neurotransmitters not under conscious control. Actually only about 17% of your brain is capable of responding to your conscious will; the rest is pretty much like that of a lower mammal or newborn baby with reactions to input based on association with imminent danger, risk, or pleasure."

"Case histories make contributions to science and practice, but they can also be highly misleading. We illustrate with our re-examination of the case of Jane Doe; she was videotaped twice, once when she was six years old and then eleven years later when she was seventeen. During the first interview she reported sexual abuse by her mother. During the second interview she apparently forgot and then remembered the sexual abuse. Jane's case has been hailed by some as the new proof of recovery of repressed or dissociated traumatic memories, and even as proof of the reliability of recovered memories of repeated abuse. Numerous pieces of "supporting evidence" were given in the original article for believing that the abuse occurred. Upon closer scrutiny, however, there are reasons to doubt not only the "supporting evidence," but also that the sexual abuse ever happened in the first place. Our analysis raises several general questions about the use of case histories in science, medicine, and mental health. There is a cautionary tale not only for those professionals who advance the case history, but also for those who base their theories on it or would readily accept it as proof."

"Why do we sleep? We spend a third of our lives doing so, and all known animals with a nervous system either sleep, or show some kind of related behaviour. But scientists still don't know what the point of it is. There are plenty of theories. Some researchers argue that sleep has no specific function, but rather serves as evolution's way of keeping us inactive, to save energy and keep us safely tucked away at those times of day when there's not much point being awake. On this view, sleep is like hibernation in bears, or even autumn leaf fall in trees. But others argue that sleep has a restorative function-something about animal biology means that we need sleep to survive. This seems like common sense. Going without sleep feels bad, after all, and prolonged sleep deprivation is used as a form of torture. We also know that in severe cases it can lead to mental disturbances, hallucinations and, in some laboratory animals, eventually death. Waking up after a good night's sleep, you feel restored, and many studies have shown the benefits of sleep for learning, memory, and cognition. Yet if sleep is beneficial, what is the mechanism? Recently, some neuroscientists have proposed that the function of sleep is to reorganize connections and "prune" synapses-the connections between brain cells. Last year, one group of researchers, led by Gordon Wang of Stanford University reviewed the evidence for this idea in a paper called Synaptic plasticity in sleep: learning, homeostasis and disease."

"As neurologists, psychologists and biologists have zeroed in more and more precisely on the physical causes of mental disorders, they have found themselves addressing a much deeper mystery, a set of interrelated conundrums probably as old as humanity: What, precisely, is the mind, the elusive entity where intelligence, decision making, perception, awareness and sense of self reside? Where is it located? How does it work? Does it arise from purely physical processes-pulses of electricity zapping from brain cell to brain cell, helped along their way by myriad complex chemicals? Or is it something beyond the merely physical-something ethereal that might be close to the spiritual concept of the soul? Great thinkers have had no shortage of ideas on the subject. Plato was convinced that the mind must be located inside the head, because the head is shaped more or less like a sphere, his idea of the highest geometrical form. Aristotle insisted that the mind was in the heart. His reasoning: warmth implies vitality; the blood is warm; the heart pumps the blood. By the Middle Ages, though, pretty much everyone agreed that the mind arose from the brain -- but still had no clear idea how it arose. Finally, in the 17th century, the French philosopher Rena Descartes declared that the mind, while it might live in the brain, was a nonmaterial thing, entirely separate from the physical tissues found inside the head. Furthermore, said Descartes in one of history's most memorable sound bites, "Cogito, ergo sum" (I think, therefore I am). His point: consciousness is the only sure evidence that we actually exist. Until just a few years ago, unraveling the relationship of mind and brain was beyond the realm of observation and experimentation. But science has finally begun to catch up with philosophy. Using sensitive electrodes inserted deep into the gray matter of test animals, researchers have watched vision as it percolates inward from the eye's retina to the inner brain. Powerful te

"Science all but confirms that humans are hard-wired to respond to music. Studies also suggest that someday music may even help patients heal from Parkinson's disease or a stroke. In The Power of Music, Elena Mannes explores how music affects different groups of people and how it could play a role in health care. Mannes tracked the human relationship with music over the course of a life span. She tells NPR's Neal Conan that studies show that infants prefer "consonant intervals, the smooth-sounding ones that sound nice to our Western ears in a chord, as opposed to a jarring combination of notes." In fact, Mannes says the cries of babies just a few weeks old were found to contain some of the basic intervals common to Western music. She also says scientists have found that music stimulates more parts of the brain than any other human function. That's why she sees so much potential in music's power to change the brain and affect the way it works. Mannes says music also has the potential to help people with neurological deficits. "A stroke patient who has lost verbal function - those verbal functions may be stimulated by music," she says. One technique, known as melodic intonation therapy, uses music to coax portions of the brain into taking over for those that are damaged. In some cases, it can help patients regain their ability to speak. And because of how we associate music with memories, Mannes says such techniques could also be helpful for Alzheimer's patients. Less recently, archaeologists have discovered ancient flutes - one of which is presumed to be the oldest musical instrument in the world - that play a scale similar to the modern Western scale. "And remarkably," Mannes says, "this flute, when played, produces these amazingly pure tones." It's a significant discovery because it adds to the argument that musical ability and interest were present early in human history."

"In the 1980s, Dr. Lars Olov Bygren, a preventive-health specialist who is now at the prestigious Karolinska Institute in Stockholm, began to wonder what long-term effects the feast and famine years might have had on children growing up in Norrbotten in the 19th century - and not just on them but on their kids and grandkids as well. So he drew a random sample of 99 individuals born in the Overkalix parish of Norrbotten in 1905 and used historical records to trace their parents and grandparents back to birth. By analyzing meticulous agricultural records, Bygren and two colleagues determined how much food had been available to the parents and grandparents when they were young. Around the time he started collecting the data, Bygren had become fascinated with research showing that conditions in the womb could affect your health not only when you were a fetus but well into adulthood. In 1986, for example, the Lancet published the first of two groundbreaking papers showing that if a pregnant woman ate poorly, her child would be at significantly higher than average risk for cardiovascular disease as an adult. Bygren wondered whether that effect could start even before pregnancy: Could parents' experiences early in their lives somehow change the traits they passed to their offspring? (See the top 10 medical breakthroughs of 2009.) It was a heretical idea. After all, we have had a long-standing deal with biology: whatever choices we make during our lives might ruin our short-term memory or make us fat or hasten death, but they won't change our genes - our actual DNA. Which meant that when we had kids of our own, the genetic slate would be wiped clean. What's more, any such effects of nurture (environment) on a species' nature (genes) were not supposed to happen so quickly. Charles Darwin, whose On the Origin of Species celebrated its 150th anniversary in November, taught us that evolutionary changes take place over many generations and through millions of years of nat

"The scientists exchanged one last look and held their breath. Everything was ready. The electrode was in place, threaded between the two hemispheres of a living cat's brain; the instruments were tuned to pick up the chatter passing from one half to the other. The only thing left was to listen for that electronic whisper, the brain's own internal code. The amplifier hissed - the three scientists expectantly leaning closer - and out it came, loud and clear. "We all live in a yellow submarine, yellow submarine, yellow submarine ...." "The Beatles' song! We somehow picked up the frequency of a radio station," recalled Michael S. Gazzaniga, chuckling at the 45-year-old memory. "The brain's secret code. Yeah, right!" Dr. Gazzaniga, 71, now a professor of psychology at the University of California, Santa Barbara, is best known for a dazzling series of studies that revealed the brain's split personality, the division of labor between its left and right hemispheres. But he is perhaps next best known for telling stories, many of them about blown experiments, dumb questions and other blunders during his nearly half-century career at the top of his field. "

"SPEAKING two languages rather than just one has obvious practical benefits in an increasingly globalized world. But in recent years, scientists have begun to show that the advantages of bilingualism are even more fundamental than being able to converse with a wider range of people. Being bilingual, it turns out, makes you smarter. It can have a profound effect on your brain, improving cognitive skills not related to language and even shielding against dementia in old age. This view of bilingualism is remarkably different from the understanding of bilingualism through much of the 20th century. Researchers, educators and policy makers long considered a second language to be an interference, cognitively speaking, that hindered a child's academic and intellectual development. They were not wrong about the interference: there is ample evidence that in a bilingual's brain both language systems are active even when he is using only one language, thus creating situations in which one system obstructs the other. But this interference, researchers are finding out, isn't so much a handicap as a blessing in disguise. It forces the brain to resolve internal conflict, giving the mind a workout that strengthens its cognitive muscles. Bilinguals, for instance, seem to be more adept than monolinguals at solving certain kinds of mental puzzles. In a 2004 study by the psychologists Ellen Bialystok and Michelle Martin-Rhee, bilingual and monolingual preschoolers were asked to sort blue circles and red squares presented on a computer screen into two digital bins - one marked with a blue square and the other marked with a red circle. In the first task, the children had to sort the shapes by color, placing blue circles in the bin marked with the blue square and red squares in the bin marked with the red circle. Both groups did this with comparable ease. Next, the children were asked to sort by shape, which was more challenging because it required placing the images in a bin m