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"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."

"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."

"Exposure to even dim light at night is enough to cause physical changes in the brains of hamsters that may be associated with depression, a new study shows."

"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

"An army hospital in Tacoma, Wash. is under fire for reneging on mental health care for troops diagnosed with post-traumatic stress disorder. Since 2007, more than 300 soldiers under consideration for medical retirement because of PTSD had their diagnoses reversed by a screening team at Madigan Army Medical Center -- a move criticized for putting costs before care. "Over 40 percent of those service members who walked in the door with a PTSD diagnosis had their diagnosis changed to something else or overturned entirely," Sen. Patty Murray said at a Defense Appropriations Subcommittee hearing Wednesday. "In light of all the tragedies we have seen that stem from the untreated, invisible wounds of war, I'm sure that you would agree that this is very concerning." PTSD is an anxiety disorder brought on by a traumatic event. The symptoms -- from anger and hypervigilance to numbness and avoidance, not to mention recurrent nightmares and terrifying flashbacks -- can wreak havoc on a person's personal and professional life. A 2010 study by Walter Reed Army Institute of Research found up to 30 percent of Iraq war veterans have symptoms of PTSD. The diagnosis can cost taxpayers as much as $1.5 million per soldier, according to an Army Medical Command memo obtained by the Seattle Times. "The challenges of PTSD and mental health care are real. And no one -- no one -- should be denying any service member purely because of a question of cost," said Murray. "That is something the tax payers of this country bear the burden of providing. We will provide it." Madigan is currently under investigation by the U.S. Army Medical Command for the reversed diagnoses. But Murray argued the investigation should be military-wide. "I want to make sure that we are really looking not just at Madigan… but system-wide," she said, adding that cost should not stand in the way of soldiers getting "the care that they have earned and they deserve and that this country expects them to have." Army

"One day last summer, Anne and her husband, Miguel, took their 9-year-old son, Michael, to a Florida elementary school for the first day of what the family chose to call "summer camp." For years, Anne and Miguel have struggled to understand their eldest son, an elegant boy with high-planed cheeks, wide eyes and curly light brown hair, whose periodic rages alternate with moments of chilly detachment. Michael's eight-week program was, in reality, a highly structured psychological study - less summer camp than camp of last resort. Michael's problems started, according to his mother, around age 3, shortly after his brother Allan was born. At the time, she said, Michael was mostly just acting "like a brat," but his behavior soon escalated to throwing tantrums during which he would scream and shriek inconsolably. These weren't ordinary toddler's fits. "It wasn't, 'I'm tired' or 'I'm frustrated' - the normal things kids do," Anne remembered. "His behavior was really out there. And it would happen for hours and hours each day, no matter what we did." For several years, Michael screamed every time his parents told him to put on his shoes or perform other ordinary tasks, like retrieving one of his toys from the living room. "Going somewhere, staying somewhere - anything would set him off," Miguel said. These furies lasted well beyond toddlerhood. At 8, Michael would still fly into a rage when Anne or Miguel tried to get him ready for school, punching the wall and kicking holes in the door. Left unwatched, he would cut up his trousers with scissors or methodically pull his hair out. He would also vent his anger by slamming the toilet seat down again and again until it broke. When Anne and Miguel first took Michael to see a therapist, he was given a diagnosis of "firstborn syndrome": acting out because he resented his new sibling. While both parents acknowledged that Michael was deeply hostile to the new baby, sibling rivalr

"Modern art is an explosion of colors, smooth lines, flat portraits - and it turns out, neuroscience. It also once triggered some strong psychology. A pot of paint has been flung in the face of the public," the criticCamille Mauclair, said in outrage over a Paris showing of the artist Henri Matisse's vibrant works. His condemnation today seems more colorful than the paintings themselves, many now hanging in museums all over the world. What was really going on at the turn of the last century to excite such controversy? Brain researchers have increasingly turned their eyes on artists, in an effort to enrich our understanding of how we see art and of the time when paintings could shake society. "When we look at a picture and feel rewarded, we know something is occurring in our brain," says neuroscientist and artist Bevil Conway of Wellesley (Mass.) College. Conway and other neuroscientists, such as Nobel Prize winner Eric Kandel, author of the just-released The Age of Insight: The Quest to Understand the Unconscious in Art, Mind, and Brain, represent the latest voices among brain researchers taking a look at art. "By closely examining artists' paintings and practices, we can discover hints to how the brain works, and achieve insight into the discoveries and inventions of artists and their impact on culture," Conway writes in the current Annals of the New York Academy of Sciences, looking at color in the paintings of Matisse , Paul Cezanne and Claude Monet . Public domain Montross Gallery 1915 exhibition catalogue image of 'Gold Fish' by Henri Matisse. Color depends on more than the wavelength of light reaching your eye. Five decades ago, brain researchers thought only the cone-shaped "photoreceptor" cells in the retina determined what colors we see. But we now know that starting from the retina and proceeding through at least five brain regions, our perception of color is shaped not so much by the redness of the paint used to hang an apple from a tree, but

As behavioral genetics enters a second century, the field's oldest research method remains both relevant and controversial. "Twins have a special claim upon our attention; it is, that their history affords means of distinguishing between the effects of tendencies received at birth, and those that were imposed by the special circumstances of their after lives." -- Sir Francis Galton, 19th century behavioral genetics pioneer, Inquiries into Human Faculty and its Development,1875 More than a century after Galton's observation, twin studies remain a favorite tool of behavioral geneticists. Researchers have used twin studies to try to disentangle the environmental and genetic backgrounds of a cornucopia of traits, from aggression to intelligence to schizophrenia to alcohol dependence. But despite the popularity of twin studies, some psychologists have long questioned assumptions that underlie them--like the supposition that fraternal and identical twins share equal environments or that people choose mates with traits unlike their own. The equal environments assumption, for example, has been debated for at least 40 years. Many researchers have found evidence that the assumption is valid, but others remain skeptical (see Further Reading below). Overall, twin studies assumptions remain controversial, says psychologist James Jaccard, PhD, a psychologist who studies statistical methods at the University at Albany of the State University of New York. In response, though, researchers are working to expand and develop twin study designs and statistical methods. And while the assumptions question remains a stumbling block for some researchers, many agree twin studies will continue to be an important tool--along with emerging genome and molecular research methods (see article page 42)--in shedding light on human behavioral genetics."

"The hormone oxytocin has come under intensive study in light of emerging evidence that its release contributes to the social bonding that occurs between lovers, friends, and colleagues. Oxytocin also plays an important role in birth and maternal behavior, but until now, research had never addressed the involvement of oxytocin in the transition to fatherhood."

"These points are extremely well-taken, particularly his last comments about the use of brain scans as indications of the brain's functions. I'm delighted to see a scientist of Gazzaniga's stature provide these cautions. Others have also worried about the over-interpretations of brain scans, a question I raised in my Psychology Today blog posting "MRI's: The new phrenology?" How many times have you heard the expression "the brain lights up"? The brain does not behave in technicolor; it's just that the colors make for a better story when researchers are trying to sell their results to the public and funding agencies. It's important that we not over-interpret the pretty colors that brain scans provide but instead recognize that everyone's brain is a little bit different and that activity in a region doesn't signify exactly what a person is thinking or feeling. I hope that we will keep these cautions in mind even as brain scans become more and more commonplace. "