Things are heating up in the world of genetics. The hot pepper (Capsicum annuum) is one of the most widely grown spice crops globally, playing an important role in many medicines, makeups, and meals worldwide. Although the plant’s so-called capsaicin chemical is well known for spicing things up, until now the genetic spark responsible for the pepper’s pungency was unknown. A team of scientists recently completed the first high-quality reference genome for the hot pepper. Comparing the pepper’s genome with that of its tame cousin, the tomato, the scientists discovered the gene responsible for fiery capsaicin production appeared in both plants. While the tomato carried four nonfunctioning copies of the gene, the hot pepper carried seven nonfunctioning copies and one functioning copy, the team reports online today in Nature Genetics. The researchers believe the pepper’s capsaicin-creating gene appeared after five mutations occurred during DNA replication, with the final mutation creating a functional copy. The mouth-burning chemicals likely protected the mutant pepper’s seeds from grazing land animals millions of years ago, giving the mutant a reproductive advantage and helping the mutant gene spread. The team says the finding could help breeders boost the pepper’s heat, nutrition, and medicinal properties. One researcher even suggests that geneticists could activate one of the tomato’s dormant genes, enabling capsaicinoid production and creating a plant that makes ready-made salsa. © 2014 American Association for the Advancement of Science.

Keyword: Pain & Touch; Evolution
Link ID: 19151 - Posted: 01.20.2014

A clean slate—that’s what people suffering from posttraumatic stress disorder (PTSD) crave most with their memories. Psychotherapy is more effective at muting more recent traumatic events than those from long ago, but a new study in mice shows that modifying the molecules that attach to our DNA may offer a route to quashing painful memories in both cases. One of the most effective treatments for PTSD is exposure psychotherapy. A behavioral psychologist asks a patient to recall and confront a traumatic event; each time the traumatic memory is revisited, it becomes susceptible to editing through a phenomenon known as memory reconsolidation. As the person relives, for example, a car crash, the details of the event—such as the color and make of the vehicle—gradually uncouple from the anxiety, reducing the likelihood of a panic attack the next time the patient sees, say, a red Mazda. Repeated therapy sessions can also lead to memory extinction, in which the fears tied to an event fade away as old memories are replaced with new ones. Yet this therapy works only for recent memories. If too much time passes before intervention, the haunting visions become stalwart, refusing to budge from the crevices of the mind. This persistence raises the question of how the brain tells the age of a memory in the first place. Researchers at the Massachusetts Institute of Technology, led by neurobiologist Li-Huei Tsai, have now uncovered a chemical modification of DNA that regulates gene activity and dictates whether a memory is too old for reconsolidation in mice. A drug that tweaks these “memory wrinkles” gives old memories a face-lift, allowing them to be edited by reconsolidation and resulting in fear extinction during behavior therapy. © 2014 American Association for the Advancement of Science.

Keyword: Learning & Memory; Stress
Link ID: 19150 - Posted: 01.18.2014

By SABRINA TAVERNISE WASHINGTON — In a broad review of scientific literature, the nation’s top doctor has concluded that cigarette smoking — long known to cause lung cancer and heart disease — also causes diabetes, colorectal and liver cancers, erectile dysfunction and ectopic pregnancy. In a report to the nation to be released on Friday, the acting surgeon general, Dr. Boris D. Lushniak, significantly expanded the list of illnesses that cigarette smoking has been scientifically proved to cause. The other health problems the report names are vision loss, tuberculosis, rheumatoid arthritis, impaired immune function and cleft palates in children of women who smoke. Smoking has been known to be associated with these illnesses, but the report was the first time the federal government concluded that smoking causes them. The finding does not mean that smoking causes all cases of the health problems and diseases listed in the report, but that some of the cases would not have happened without smoking. The surgeon general has added to the list of smoking-related diseases before. Bladder cancer was added in 1990 and cervical cancer in 2004. When President Nixon signed the National Cancer Act many expected quick results, comparing the effort to the one that put man on the moon. After 42 years, what progress have we made? The report is not legally binding, but is broadly held as a standard for scientific evidence among researchers and policy makers. Experts not involved in writing the report said the findings were a comprehensive summary of the most current scientific evidence, and while they might not be surprising to researchers, they were intended to inform the public as well as doctors and other medical professionals about the newest proven risks of smoking. © 2014 The New York Times Company

Keyword: Drug Abuse
Link ID: 19149 - Posted: 01.18.2014

Overweight and obese adults who drink diet pop also tend to eat more calories each day from food, a finding that hints at how relying on diet beverages for weight loss could be a mistake. In this week’s issue of the American Journal of Public Health, researchers from Johns Hopkins Bloomberg School of Public Health in Baltimore analyzed U.S. survey data for 24,000 people from 1999 to 2010. They looked for patterns in beverage consumption and calories. The sweet taste of beverages, whether from sugar or artificial sweeteners, seems to enhance our appetite and encourage cravings for sugar. (Rob Carr/Associated Press) Overweight consumers of diet beverages took in 1,965 in food calories a day compared with 1,874 calories among those in the same weight class who drank beverages sweetened with sugar, such as non-diet soda, sports drinks, fruit drinks and sweetened tea. As people increasingly switch to diet beverages, the focus on reducing sugar from drinks might not be enough to lose weight in the long term, the researchers concluded. "The switch from a sugary beverage to a diet beverage should be coupled with other changes in the diet, particularly reducing snacks," suggested lead author Sara Bleich. In the study, snacking patterns were generally the same between diet and sugary beverage drinkers. The researchers said the finding is consistent with evidence that the sweet taste of beverages, whether from sugar or artificial sweeteners, enhances our appetite and encourage cravings for sugar. © CBC 2014

Keyword: Obesity
Link ID: 19148 - Posted: 01.18.2014

-- Bats and other animals use ultrasound to their advantage. Now a new study of humans suggests ultrasound can alter brain activity to boost people's sensory perception. First, researchers placed an electrode on the wrist of volunteers to stimulate the nerve that runs down the arm and into the hand. Before stimulating the radial nerve, they delivered ultrasound to the head -- to an area of the cerebral cortex that processes sensory information received from the hand. The participants' brain responses were recorded using electroencephalography (EEG). The ultrasound decreased the EEG signal and weakened the brain waves responsible for processing sensory input from the hands, according to the study published online Jan. 12 in the journal Nature Neuroscience. The Virginia Tech researchers then conducted two common neurological tests. One measures a person's ability to distinguish whether two pins placed close together and touching the skin are actually two distinct contact points. The other test measures sensitivity to the frequency of a series of air puffs. The scientists were surprised to discover that when they received ultrasound, the participants showed significant improvements in their ability to distinguish pins at closer distances and to identify small differences in the frequency of successive air puffs. The ultrasound may have changed the balance of inhibition and excitation between neighboring neurons within the cerebral cortex, resulting in a boost in sensory perception, explained study leader William Tyler, an assistant professor at Virginia Tech's Carilion Research Institute. © 2014 HealthDay

Keyword: Pain & Touch
Link ID: 19147 - Posted: 01.18.2014

By Melissa Healy Adolescents treated with the antidepressant fluoxetine -- better known by its commercial name, Prozac -- appear to undergo changes in brain signaling that result in changed behavior well into adulthood, says a new study. Adult mice and rats who were administered Prozac for a stretch of mid-adolescence responded to daunting social and physical challenges with less despair than animals who passed their teen years unmedicated, a team of researchers found. But, even as adults long separated from their antidepressant days, the Prozac veterans reacted to stressful situations with greater anxiety than did the adult Prozac virgins. The latest research, published Wednesday in the Journal of Neuroscience, offers evidence that treatment with a selective serotonin reuptake inhibitor -- an SSRI antidepressant -- has long-lived effects on the developing brain. It also zeroes in on how and where fluoxetine effects those lasting changes: by modifying the cascade of chemical signals issued by the brain's ventral tegmentum -- a region active in mood regulation -- in stressful situations. Yet, the new research raises more questions than it answers, since the changes in adults who were treated with Prozac as adolescents seem contradictory. Sensitivity to stress appears to predispose one to developing depression. So how does a medication that treats depression in children and teens -- and that continues to protect them from depression as adults -- also heighten their sensitivity to stress?

Keyword: Depression; Development of the Brain
Link ID: 19146 - Posted: 01.18.2014

By Evelyn Boychuk, Caleb is a 14-year-old who enjoys playing video games and reading any book he can get his hands on – and in his spare time, he edits neuroscience papers for a scientific journal. Frontiers for Young Minds is the first journal to bring kids into the middle of the scientific process by making them editors – and it’s free for everyone. The idea came “from the depths of my mind, in a moment when I was bored at a scientific meeting,” says Bob Knight, editor in chief of Frontiers for Young Minds and a professor of psychology and neuroscience at the University of California, Berkeley. This is one of many science outreach efforts that are trying to get youth excited about science, technology, engineering and math courses. A preview version with 15 articles was released at the Society for Neuroscience conference on Nov. 11. The official launch of the monthly journal is planned for the U.S.A. Science and Engineering Festival in Washington D.C. in April. “The kids have been great,” says Knight. “Their reviews are not filtered, they just tell you what they think.” In an e-mail, one of the young editors said, “'Hey Bob, I have to tell you, I didn’t understand anything in this article. The words are too big and it’s too confusing,'” Knight recounted. When Caleb was asked if he would edit an article for this preview, "it seemed like an interesting opportunity," he said, so he gave it a try. © CBC 2014

Keyword: Miscellaneous
Link ID: 19145 - Posted: 01.18.2014

By TRICIA ROMANO Like many men of his generation, Larry Faust, 61, of Seattle, went to a lot of rock concerts in his youth. And like many men of his generation, his hearing isn’t what it used to be. “My wife has been bugging me for several years to do something about my hearing,” said Mr. Faust. “I spent part of the summer of 1969 at Woodstock. So that probably didn’t help.” Instead of going the traditional route — buying hearing aids through an audiologist or licensed hearing aid dispenser — Mr. Faust purchased a device that is classified as a personal sound amplifier product, or P.S.A.P., which is designed to amplify sounds in a recreational environment. Unlike hearing aids, P.S.A.P.’s are exempt from Food and Drug Administration oversight and can be sold as electronic devices directly to consumers, with no need to see a physician before buying one. They come with a range of features and vary widely in price. And while some hearing professionals have long cautioned against the devices, citing their unreliability and poor quality, many also say that a new generation of P.S.A.P.s that utilize the latest wireless technology are offering promising alternatives for some people with hearing loss. The device Mr. Faust bought, the CS10 from a Chicago-based company called Sound World Solutions, cost $299.99, thousands of dollars cheaper than most digital hearing aids. While it has many of the same features that high-end hearing aids have, including 16 channels to process sound, directional microphones, feedback insulation and noise reduction, it has one capability that hearing aids and other devices on the market currently don’t have. It comes with software that enables consumers to program it themselves, a feature made possible in part by the adoption of the widely available Bluetooth wireless technology, rather than the proprietary platforms used by most wireless hearing aids. © 2014 The New York Times Company

Keyword: Hearing
Link ID: 19144 - Posted: 01.16.2014

Ian Sample, science correspondent Two men with progressive blindness have regained some of their vision after taking part in the first clinical trial of a gene therapy for the condition. The men were among six patients to have experimental treatment for a rare, inherited, disorder called choroideremia, which steadily destroys eyesight and leaves people blind in middle age. After therapy to correct a faulty gene, the men could read two to four more lines on an optician's sight chart, a dramatic improvement that has held since the doctors treated them. One man was treated more than two years ago. The other four patients, who had less advanced disease and good eyesight before the trial, had better night vision after the therapy. Poor sight in dim light is one of the first signs of the condition. Writing in The Lancet , doctors describe the progress of the patients six months after the therapy. If further trials are as effective, the team could apply for approval for the therapy in the next five years. Some other forms of blindness could be treated in a similar way. Toby Stroh, 56, a solicitor from London, was in his early 20s when a consultant told him he would be blind by the age of 50. "I said 'what do you mean?' and he said, 'you won't be able to see me'. It was a long way away, but still a bit of a shock." Stroh was told later that his vision had deteriorated so much he would have to stop driving. Then, when he joined a solicitors' firm he told a partner his eyesight was not expected to last. The response was: "We'll be sorry to see you go." © 2014 Guardian News and Media Limited

Keyword: Vision
Link ID: 19143 - Posted: 01.16.2014

By DAN HURLEY Two and a half millenniums ago, a prince named Siddhartha Gautama traveled to Bodh Gaya, India, and began to meditate beneath a tree. Forty-nine days of continuous meditation later, tradition tells us, he became the Buddha — the enlightened one. More recently, a psychologist named Amishi Jha traveled to Hawaii to train United States Marines to use the same technique for shorter sessions to achieve a much different purpose: mental resilience in a war zone. “We found that getting as little as 12 minutes of meditation practice a day helped the Marines to keep their attention and working memory — that is, the added ability to pay attention over time — stable,” said Jha, director of the University of Miami’s Contemplative Neuroscience, Mindfulness Research and Practice Initiative. “If they practiced less than 12 minutes or not at all, they degraded in their functioning.” Jha, whose program has received a $1.7 million, four-year grant from the Department of Defense, described her results at a bastion of scientific conservatism, the New York Academy of Sciences, during a meeting on “The Science of Mindfulness.” Yet mindfulness hasn’t long been part of serious scientific discourse. She first heard another scientist mention the word “meditation” during a lecture in 2005. “I thought, I can’t believe he just used that word in this audience, because it wasn’t something I had ever heard someone utter in a scientific context,” Jha said. Although pioneers like Jon Kabat-Zinn, now emeritus professor at the University of Massachusetts Medical Center, began teaching mindfulness meditation as a means of reducing stress as far back as the 1970s, all but a dozen or so of the nearly 100 randomized clinical trials have been published since 2005. And the most recent studies of mindfulness — the simple, nonjudgmental observation of a person’s breath, body or just about anything else — are taking the practice in directions that might have shocked the Buddha. In addition to military fitness, scientists are now testing brief stints of mindfulness training as a means to improve scores on standardized tests and lay down new connections between brain cells. © 2014 The New York Times Company

Keyword: Attention; Consciousness
Link ID: 19142 - Posted: 01.16.2014

By Meeri Kim, Rats, like humans, will show kindness to strangers, but only if the rats in distress are of a familiar type, a new study has found. Neurobiologists from the University of Chicago have discovered that rats display empathy-like behavior toward other rats, but the basis of that empathy is environmental, rather than genetic. The creatures aren’t born with an innate motivation to help rats of their own kind, but instead those with whom they are socially familiar. “Rats choose to help according to which rats they’ve had a positive social experience with in the past,” said study author and postdoctoral researcher Inbal Ben-Ami Bartal. As part of what Bartal calls the “Mowgli experiment” — a reference to the boy raised by wolves in Rudyard Kipling’s “The Jungle Book” — researchers plucked albino pups from their mothers on the day they were born and transferred them to a group of black-patched rats. As adults, the albinos refused to help other albinos but readily freed black-patched rats. “There’s no mirror in nature,” said study author and neurobiologist Peggy Mason. “They are not born with an idea of who they are, and therefore, who they should help.” The study was published online Tuesday in the journal eLife. © 1996-2014 The Washington Post

Keyword: Emotions; Genes & Behavior
Link ID: 19141 - Posted: 01.16.2014

Dan Hurley Forget mindfulness meditation, computerized working-memory training, and learning a musical instrument; all methods recently shown by scientists to increase intelligence. There could be an easier answer. It turns out that sex might actually make you smarter. Researchers in Maryland and South Korea recently found that sexual activity in mice and rats improves mental performance and increases neurogenesis (the production of new neurons) in the hippocampus, where long-term memories are formed. In April, a team from the University of Maryland reported that middle-aged rats permitted to engage in sex showed signs of improved cognitive function and hippocampal function. In November, a group from Konkuk University in Seoul concluded that sexual activity counteracts the memory-robbing effects of chronic stress in mice. “Sexual interaction could be helpful,” they wrote, “for buffering adult hippocampal neurogenesis and recognition memory function against the suppressive actions of chronic stress.” So growing brain cells through sex does appear to have some basis in scientific fact. But there’s some debate over whether fake sex—pornography—could be harmful. Neuroscientists from the University of Texas recently argued that excessive porn viewing, like other addictions, can result in permanent “anatomical and pathological” changes to the brain. That view, however, was quickly challenged in a rebuttal from researchers at the University of California, Los Angeles, who said that the Texans "offered little, if any, convincing evidence to support their perspectives. Instead, excessive liberties and misleading interpretations of neuroscience research are used to assert that excessive pornography consumption causes brain damage." © 2014 by The Atlantic Monthly Group

Keyword: Sexual Behavior; Neurogenesis
Link ID: 19140 - Posted: 01.16.2014

Injuries to the head can leave victims susceptible to early death even years later through impaired judgement, a major analysis of survivors shows. Those with a history of psychiatric disorders before the injury are most at risk of dying prematurely. The study, in JAMA Psychiatry, of 40 years of data on more than two million people, showed that overall a brain injury trebled the risk. Suicide and fatal injuries were among the commonest causes of early death. More than one million people in Europe are taken to hospital with a traumatic brain injury each year. The study, by researchers at the University of Oxford and the Karolinska Institute in Stockholm, looked at Swedish medical records between 1969 and 2009. They followed patients who survived the initial six-month danger period after injury. The data showed that without injury 0.2% of people were dying prematurely - before the age of 56. However, the premature-death rate was three-fold higher in patients who had previously suffered traumatic brain injury. In those who also had a psychiatric disorder the rate soared to 4%. Dr Seena Fazel, one of the researchers in Oxford, said: "There are these subgroups with really high rates, and these are potentially treatable illnesses, so this is something we can do something about." BBC © 2014

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 19139 - Posted: 01.16.2014

By ANAHAD O'CONNOR Scientists call it the obesity paradox, the notion that being overweight or moderately obese lowers the risk of an early death. They have documented the phenomenon in large population studies and in groups of patients with chronic diseases like hypertension and Type 2 diabetes. But now a new report, published on Wednesday in The New England Journal of Medicine, is calling the obesity paradox into question, at least for patients with Type 2 diabetes. The study, of nearly 12,000 people with the disease, found that there was no survival advantage for those who had a body mass index that put them in the overweight or obese categories. Instead, the researchers found that the diabetics with the lowest mortality rate were those who were considered normal weight. The study is among the largest to examine the obesity paradox among people with Type 2 diabetes, an illness that afflicts more than 25 million Americans. The authors argue that previous studies showing a protective effect of a high B.M.I. among diabetics were flawed because they were too small or failed to account for factors like smoking or undiagnosed illnesses that can contribute to low body weight but a shorter life span as well. The new study found that when smoking and other factors that can contribute to weight loss were accounted for, people in the highest B.M.I. groups had higher mortality rates. “I think the case is not necessarily closed,” said Deirdre K. Tobias, the lead author of the paper and a research fellow at the Harvard School of Public Health. “But at this point, there is no reason to believe that being overweight or obese would be protective for people with diabetes.” © 2014 The New York Times Company

Keyword: Obesity
Link ID: 19138 - Posted: 01.16.2014

A new website that helps determine whether someone might have Alzheimer's disease or dementia is so popular that the site crashed temporarily. Ohio State University's website says its Self-Administered Gerocognitive Exam (SAGE) is a test that can be done in your own home with a paper and pencil. When researchers visited 45 community events where they asked people to take the simple test, they found that of the 1, 047 who did it, 28 per cent were identified with cognitive impairment, test developer Dr. Douglas Scharre of Ohio State and his team reported Monday in The Journal of Neuropsychiatry and Clinical Neurosciences. Alzheimer's test Researchers in Ohio say the SAGE test has been shown to be effective in spotting the early signs of cognitive decline. (Ohio State University Wexner Medical Center) Participants were told the test represented their baseline level, which doctors could use for future comparisons during re-screening. "What we found was that this SAGE self-administered test correlated very well with detailed cognitive testing," Scharre said in a release. "If we catch this cognitive change really early, then we can start potential treatments much earlier than without having this test." The Alzheimer Society of Canada says early diagnosis can help with planning, care and support. © CBC 2014

Keyword: Alzheimers
Link ID: 19137 - Posted: 01.16.2014

By ANDREW POLLACK Launch media viewer Kristin Tremblay helps make dinner at home in Gainesville, Fla. She has a disorder that makes her uncontrollably hungry. Rob C. Witzel for The New York Times Lisa Tremblay still recalls in horror the time her daughter Kristin pulled a hot dog crawling with ants from the garbage at a cookout and prepared to swallow it. Kristin has a rare genetic abnormality that gives her an incessant, uncontrollable hunger. Some people with the condition, called Prader-Willi syndrome, will eat until their stomach ruptures and they die. And, not surprisingly, many are obese. “She’s eaten dog food. She’s eaten cat food,” said Ms. Tremblay, who lives in Nokomis, Fla. When Kristin, now 28, was a child, neighbors once called social welfare authorities, thinking Kristin was not being fed because she complained of being hungry so much. Once an obscure and neglected disease, Prader-Willi is starting to attract more attention from scientists and pharmaceutical companies for a simple reason: It may shed some light on the much broader public health problems of overeating and obesity. “These are remarkable human models of severe obesity,” said Dr. Steven B. Heymsfield, a professor and former executive director of the Pennington Biomedical Research Center in Baton Rouge, La. “When we discover the underlying mechanism of these very rare disorders, they will shed light on garden-variety obesity.” One drug being developed to help obese people lose weight has shown some preliminary signs of success in patients with Prader-Willi. The drug, beloranib, is believed to work by reducing fat synthesis and increasing fat use. In a small trial, it reduced weight and body fat and lowered the food-seeking urge, according to the drug’s developer, Zafgen. © 2014 The New York Times Company

Keyword: Obesity; Genes & Behavior
Link ID: 19136 - Posted: 01.15.2014

By Emilie Reas “Come on. Get out of the express checkout lane! That’s way more than twelve items, lady.” Without having to count, you can make a good guess at how many purchases the shopper in front of you is making. She may think she’s pulling a fast one, but thanks to the brain’s refined sense for quantity, she’s not fooling anyone. This ability to perceive numerosity – or number of items – does more than help prevent express lane fraud; it also builds the foundation for our arithmetic skills, the economic system and our concept of value. Until recently, it’s remained a puzzle how the brain allows us to so quickly and accurately judge quantity. Neuroscientists believe that neural representations of most high-level cognitive concepts – for example, those involved in memory, language or decision-making – are distributed, in a relatively disorganized manner, throughout the brain. In contrast, highly organized, specialized brain regions have been identified that represent most lower-level sensory information, such as sights, sounds, or physical touch. Such areas resemble maps, in that sensory information is arranged in a logical, systematic spatial layout. Notably, this type of neural topography has only previously been observed for the basic senses, but never for a high-level cognitive function. Researchers from the Netherlands may have discovered an exception to this rule, as reported in their recently published Science paper: a small brain area which represents numerosity along a continuous “map.” Just as we organize numbers along a mental “number line,” with one at the left, increasing in magnitude to the right, so is quantity mapped onto space in the brain. One side of this brain region responds to small numbers, the adjacent region to larger numbers, and so on, with numeric representations increasing to the far end. © 2014 Scientific American,

Keyword: Attention
Link ID: 19135 - Posted: 01.15.2014

By Arthur Allen, Cognitive psychologist Mary Czerwinski and her boyfriend were having a vigorous argument as they drove to Vancouver, B.C., from Seattle, where she works at Microsoft Research. She can’t remember the subject, but she does recall that suddenly, his phone went off, and he read out the text message: “Your friend Mary isn’t feeling well. You might want to give her a call.” At the time, Czerwinski was wearing on her wrist a wireless device intended to monitor her emotional ups and downs. Similar to the technology used in lie detector tests, it interprets signals such as heart rate and electrical changes in the skin. The argument may have been trivial, but Czerwinski’s internal response was not. That prompted the device to send a distress message to her cellphone, which broadcast it to a network of her friends. Including the one with whom she was arguing, right beside her. Czerwinski is working in affective computing, which emerged in 2000 from the laboratory of Rosalind Picard at the Massachusetts Institute of Technology. Picard and her colleagues dreamed of creating caring robots. As a first step, they decided to make machines that could detect and help us cope with our sometimes hidden emotions. One of Picard’s early projects involved helping autistic children. Because her devices were often better than the children themselves at communicating their feelings, she designed ways of feeding information from a wrist sensor to the cellphones of parents and other caretakers so they could know about the stress their children were under and respond accordingly. © 1996-2014 The Washington Post

Keyword: Emotions; Robotics
Link ID: 19134 - Posted: 01.15.2014

By Ashutosh Jogalekar Popular wisdom holds that caffeine enhances learning, alertness and retention, leading millions to consume coffee or caffeinated drinks before a challenging learning task such as attending a business strategy meeting or a demanding scientific presentation. However a new study in the journal Nature Neuroscience conducted by researchers from Johns Hopkins hints that when it comes to long-term memory and caffeine, timing may be everything; caffeine may enhance consolidation of memories only if it is consumed after a learning or memory challenge. In the study the authors conducted a randomized, double-blind controlled experiment in which 160 healthy female subjects between the ages of 18 and 30 were asked to perform a series of learning tasks. The subjects were handed cards with pictures of various random indoor and outdoor objects (for instance leaves, ducks and handbags) on them and asked to classify the objects as indoor or outdoor. Immediately after the task the volunteers were handed pills, either containing 200 mg of caffeine or placebo. Saliva samples to test for caffeine and its metabolites were collected after 1, 3 and 24 hours. After 24 hours the researchers tested the participants’ recollection of the past day’s test. Along with the items in the test (‘old’) they were presented with new items (‘foils’) and similar looking items (‘lures’), neither of which were part of the task. They were then asked to again classify the items as old, new and similar. There was a statistically significant percentage of volunteers in the caffeinated group that was more likely to mark the ‘similar’ items as ‘similar’ rather than ‘old’. That is, caffeinated participants were clearly able to distinguish much better between the old and the other items, indicating that they were retaining the memory of the old items much better than the people in the placebo group. © 2014 Scientific American,

Keyword: Learning & Memory; Drug Abuse
Link ID: 19133 - Posted: 01.15.2014

By Sam Kean In 1559, the two surgeons Ambroise Paré and Andreas Vesalius discussed trepanning the skull of King Henri II of France to remove any excess fluids and “corrupted” blood inside, but the risks outweighed the benefits and they gave the idea up. In the meantime, they examined the heads of the decapitated criminals. History doesn’t record the exact methodology here—whether someone fixed each head inside a vice to provide a stable target, or perhaps strung the noggins up like piñatas to swing at—but the Count de Montgomery’s stump got quite a workout battering their mugs. It was a macabre mix of medieval brutality and modern experimental savvy, and Paré and Vesalius eagerly examined them for clues. Alas, they offered little inspiration for treatment. Instead, the two men could have learned a lot more by simply observing the king, whose suffering foreshadowed many great discoveries over the next four centuries of neuroscience. Henri continued to drift in and out of coherence, limning the borders of the unconscious. He suffered from seizures and temporary paralysis, two then-mysterious afflictions. Strangely, the paralysis or seizures would derange only half of his body at any one time, a clear hint (in retrospect) that the brain controls the body’s halves independently. Henri’s vision also went in and out, a clue that the back of the brain (where Paré expected to find the contrecoup damage) controls our sense of sight. Worst of all, Henri’s headache kept widening, which told Paré that his brain was swelling and that blood vessels had ruptured inside the skull. As we know today, inflammation and fluid pressure can crush brain cells, destroying the switches and circuits that run the body and mind. This explains why brain injuries can be lethal even if the skull suffers no fracture. Skull fractures can in fact save people’s lives, by giving the swollen brain or pools of blood room to expand into. The history of neuroscience has proved the brain amazingly resilient, but one thing it cannot stand is pressure, and the secondary effects of trauma, like swelling, often prove more deadly than the initial blow. © 2014 Time Inc.

Keyword: Brain Injury/Concussion
Link ID: 19132 - Posted: 01.15.2014