-Dominic Ramos-

You've probably heard it before: the brain is a muscle that can be strengthened. It's an assumption that has spawned a multimillion-dollar computer-game industry of electronic brainteasers and memory games. But in the largest study of these games to date, a team of British researchers has found that healthy adults who undertake computer-based "brain training" do not improve their mental fitness in any significant way.

The study, published online on Tuesday by the journal Nature, tracked 11,430 participants through a six-week online study. The participants were divided into three groups: the first group undertook basic reasoning, planning and problem-solving activities (like choosing the "odd one out" of a group of four objects); the second completed more complex exercises of memory, attention, math and visual-spatial processing that were designed to mimic popular brain-training computer games and programs; and the control group was asked to use the Internet to research answers to trivia questions.

All participants were given a battery of unrelated, benchmark cognitive-assessment tests before and after the six-week study. These tests, designed to measure overall mental fitness, were adapted from reasoning and memory tests that are commonly used to gauge brain function in patients with brain injury or dementia. All three study groups showed marginal — and identical — improvement on these benchmark exams.

But the improvement had nothing to do with the interim brain-training, says study co-author Jessica Grahn of the Cognition and Brain Sciences Unit in Cambridge, Mass. Grahn says the results confirm what she and other neuroscientists have long suspected: people who practice a certain mental task — for instance, remembering a series of numbers in sequence, a popular brainteaser used by many video games — improve dramatically on that task, but the improvement does not carry over to cognitive function in general. (Indeed, all the study participants improved in the tasks they were given; even the control group got better at looking up answers to obscure questions.) The "practice makes perfect" phenomenon probably explains why the study participants improved on the benchmark exams, says Grahn — they had all taken them once before. "People who practiced a certain test improved at that test, but improvement does not translate beyond anything other than that specific test," she says.

The authors believe the study, which was run in conjunction with the BBC television program Bang Goes the Theory, undermines the sometimes outlandish claims of brain-boosting websites and digital games. On TIME.com in 2009, Anita Hamilton wrote about HAPPYneuron, a brain-training website that invites visitors to "give the gift of brain fitness" and claims that its users see "16%+ improvement" through exercises such as learning to associate a bird's song with its species and shooting basketballs through virtual hoops. Hamilton also took note of Nintendo's best-selling game Brain Age, which promises to "give your brain the workout it needs" through exercises like solving math problems and playing Rock, Paper, Scissors on the handheld DS. However, "the widely held belief that commercially available computerized brain-training programs improve general cognitive function in the wider population lacks empirical support," the Nature paper concludes.

Not all neuroscientists agree. In 2005, Torkel Klingberg, a professor of cognitive neuroscience at the Karolinska Institute in Sweden, used brain imaging to show that brain-training can alter the number of dopamine receptors in the brain — dopamine is a neurotransmitter involved in learning and other important cognitive functions. Other studies have suggested that brain-training can help improve cognitive function in elderly patients and those in the early stages of Alzheimer's disease, but the literature is contradictory.

Klingberg has developed a brain-training program called Cogmed Working Memory Training, and owns shares in the company that distributes it. He tells TIME that the Nature study "draws a large conclusion from a single negative finding" and that it is "incorrect to generalize from one specific training study to cognitive training in general." He also criticizes the design of the study and points to two factors that may have skewed the results.

On average, the study volunteers completed 24 training sessions, each about 10 minutes long — for a total of three hours spent on different tasks over six weeks. "The amount of training was low," says Klingberg. "Ours and others' research suggests that 8 to 12 hours of training on one specific test is needed to get a [general improvement in cognition]."

Second, he notes that the participants were asked to complete their training by logging onto the BBC Lab UK website from home. "There was no quality control. Asking subjects to sit at home and do tests online, perhaps with the TV on or other distractions around, is likely to result in bad quality of the training and unreliable outcome measures. Noisy data often gives negative findings," Klingberg says.

Brain-training research has received generous funding in recent years — and not just from computer-game companies — as a result of the proven effect of neuroplasticity, the brain's ability to remodel its nerve connections after experience. The stakes are high. If humans could control that process and bolster cognition, it could have a transformative effect on society, says Nick Bostrom of Oxford University's Future of Humanity Institute. "Even a small enhancement in human cognition could have a profound effect," he says. "There are approximately 10 million scientists in the world. If you could improve their cognition by 1%, the gain would hardly be noticeable in a single individual. But it could be equivalent to instantly creating 100,000 new scientists."

For now, there is no nifty computer game that will turn you into Einstein, Grahn says. But there are other proven ways to improve cognition, albeit by small margins. Consistently getting a good night's sleep, exercising vigorously, eating right and maintaining healthy social activity have all been shown to help maximize a brain's potential over the long term.

What's more, says Grahn, neuroscientists and psychologists have yet to even agree on what constitutes high mental aptitude. Some experts say physical skill, which stems from neural pathways, should be considered a form of intelligence — in that case, masterful ballet dancers and basketball players would be considered geniuses.

Jason Allaire, co-director of the Games through Gaming lab at North Carolina State University says the Nature study makes sense; rather than finding a silver bullet for brain enhancement, he says, "it's really time for researchers to think about a broad or holistic approach that exercises or trains the mind in general in order to start to improve cognition more broadly."

Or, as Grahn puts it, when it comes to mental fitness, "there are no shortcuts."

— With reporting by Tara Kelly / London

Disciplining young children is one of the key jobs of any parent — most people would have no trouble agreeing with that. But whether or not that discipline should include spanking or other forms of corporal punishment is a far trickier issue.

The American Academy of Pediatrics (AAP) does not endorse spanking for any reason, citing its lack of long-term effectiveness as a behavior-changing tactic. Instead the AAP supports strategies such as time-outs when children misbehave, which focus on getting kids to reflect on their behavior and the consequences of their actions. Still, as many parents can attest, few responses bring about the immediate interruption of a full-blown tantrum like a swift whack to the bottom.

Now researchers at Tulane University provide the strongest evidence yet against the use of spanking: of the nearly 2,500 youngsters in the study, those who were spanked more frequently at age 3 were more likely to be aggressive by age 5. The research supports earlier work on the pitfalls of corporal punishment, including a study by Duke University researchers that revealed that infants who were spanked at 12 months scored lower on cognitive tests at age 3.

"I'm excited by the idea that there is now some nice hard data that can back up clinicians when they share their caution with parents against using corporal punishment," says Dr. Jayne Singer, clinical director of the child and parent program at Children's Hospital Boston, who was not involved in the study.

Led by Catherine Taylor, the Tulane study was the first to control simultaneously for variables that are most likely to confound the association between spanking and later aggressive behavior. The researchers accounted for factors such as acts of neglect by the mother, violence or aggression between the parents, maternal stress and depression, the mother's use of alcohol and drugs, and even whether the mother considered abortion while pregnant with the child.

Each of these factors contributed to children's aggressive behavior at age 5, but they could not explain all of the violent tendencies at that age. Further, the positive connection between spanking and aggression remained strong, even after these factors had been accounted for.

"The odds of a child being more aggressive at age 5 if he had been spanked more than twice in the month before the study began increased by 50%," says Taylor. And because her group also accounted for varying levels of natural aggression in children, the researchers are confident that "it's not just that children who are more aggressive are more likely to be spanked."

What the study, published Monday in the journal Pediatrics, shows is that outside of the most obvious factors that may influence violent behavior in children, spanking remains a strong predictor. "This study controls for the most common risk factors that people tend to think of as being associated with aggression," says Singer. "This adds more credence, more data and more strength to the argument against using corporal punishment."

Among the mothers who were studied, nearly half (45.6%) reported no spanking in the previous month, 27.9% reported spanking once or twice and 26.5% reported spanking more than twice. Compared with children who were not hit, those who were spanked were more likely to be defiant, demand immediate satisfaction of their wants and needs, get frustrated easily, have temper tantrums and lash out physically against others.

The reason for that, says Singer, may be that spanking instills fear rather than understanding. Even if a child were to stop his screaming tantrum when spanked, that doesn't mean he understands why he shouldn't be acting up in the first place. What's more, spanking models aggressive behavior as a solution to problems.

For children to understand what and why they have done something wrong, it may take repeated efforts on the parent's part, using time-outs — a strategy that typically involves denying the child any attention, praise or interaction with parents for a specified period of time (that is, the parents ignore the child). These quiet times force children to calm down and learn to think about their emotions, rather than acting out on them blindly.

Spanking may stop a child from misbehaving in the short term, but it becomes less and less effective with repeated use, according to the AAP; it also makes discipline more difficult as the child gets older and outgrows spanking. As the latest study shows, investing the time early on to teach a child why his behavior is wrong may translate to a more self-aware and in-control youngster in the long run.

Multitasking has become a way of life. Most of us think nothing of juggling a couple of chores at once, whether at home or in the office or, most dangerously, on the road. And despite some states' bans on talking while driving, as well as a raft of studies showing the potential deadliness of distracted driving, chances are good that you still have cell-phone conversations behind the wheel.

Chances are also good that you think it's O.K. because you're a truly capable multitasker. Maybe you even consider yourself one of the few supertaskers who, unlike the rest of us, are so mentally agile that they can safely talk or text — or pen a novel — while driving.

A new University of Utah study on distraction in the driver's seat finds that such virtuosos do exist: the paper, which has been accepted for publication this year in the journal Psychonomic Bulletin & Review, found that a very small percentage of participants — 2.5% to be exact — were able to do other things successfully while driving (in the study, it was solving math problems and memorizing words) without a drop in performance on any task. In fact, some of these supertaskers performed better while multitasking than they did while completing the tasks alone.

The authors of the study suggest that there may be a set of biological, genetic and perhaps behavioral factors that contribute to efficient multitasking, and that maybe some of these factors can even be learned to make the rest of us better at doing two things at once.

Jason Watson and David Strayer, psychologists at the University of Utah, assembled a group of 200 undergraduates and asked them to perform a simulated driving test as well as a standardized memory test that involved math and word memorization. Each of the students first performed these tasks separately, then simultaneously. For the multitasking portion of the experiment, researchers asked the volunteers to complete a verbal version of the memory test on a hands-free cell phone while driving in a simulator.

During the hour-and-a-half session, 97.5% of the students showed a significant decrease in their driving abilities and memory skills while multitasking. "What we think is happening for most of us when we multitask is that it's more than what our mental capacity, or mental resources in the frontal cortex, can handle," says Watson. The frontal cortex acts as a master switching station that manages where the brain focuses its immediate attention. "So our performance is going to suffer when we combine different tasks."

But a minority of students in Watson and Strayer's study — the other 2.5% — showed no declines in performance, and in some cases even logged an overall improvement in ability when various tasks were combined. This is the small subset of individuals whom the authors call supertaskers, whose brains seem to function differently from those of the rest of us.

Supertaskers can juggle simultaneous tasks without experiencing a drop in attention or focus, which flies against the conventional wisdom about how the human brain functions. Experts believe that the brain has a fixed budget of resources, with demands on its attention serving as expenses. Given the limited neuronal budget, the brain can devote only so much of its resources to any particular task; if demanding tasks pile up on each other, then each task is allotted a smaller and smaller amount of resources, which translates into a decrease in performance.

Read more: http://www.time.com/time/health/article/0,8599,1977523,00.html#ixzz0kFXuvuhu 

(Health.com) -- Eating as little as a quarter of an ounce of chocolate each day -- an amount equal to about one small Easter egg -- may lower your risk of experiencing a heart attack or stroke, a new study has found. For best results, the chocolate should be dark, experts say.

"Dark chocolate exhibits the greatest effects, milk chocolate fewer, and white chocolate no effects," says the lead author of the study, Brian Buijsse, a nutritional epidemiologist at the German Institute of Human Nutrition, in Nuthetal, Germany.

In the study, Buijsse and his colleagues followed nearly 20,000 people for an average of eight years. The researchers surveyed the study participants about their chocolate consumption (as well as the rest of their diet), and also tracked the heart attacks and strokes that occurred in the group.

Compared with people who rarely ate chocolate (about one bar per month), the people who ate the most chocolate (slightly more than one bar per week) had a 27 percent and 48 percent reduced risk of heart attack and stroke, respectively, the researchers found.

The heart benefits observed in the study may be due in part to lower blood pressure, the study notes. Previous studies have suggested that eating chocolate can lower blood pressure, and the researchers observed a similar -- though less pronounced -- association in this study.

"The good news is that chocolate is not as bad as we used to think, and may even lower the risk of heart disease and stroke," says Buijsse. "The bad news, at least for some of us, is that the amounts that are needed to benefit from these effects appear to be quite low."

In other words, these findings don't mean that you should stuff yourself with chocolate Easter eggs. Chocolate is high in calories, and, as with any such food, eating too much of it can swell your waistline and harm your health in other ways.

"This is only one small egg per day," says Buijsse. "Eating higher amounts will most likely result in weight gain. If people start eating small amounts of chocolate, it should replace something else, preferably other high-calorie sweets or snacks." The people in the study were part of a larger study on the effect of diet and lifestyle on cancer risk. For the current study, Buijsse and his colleagues excluded anyone with a history of heart disease or stroke, and also controlled for age, diet, lifestyle, and other factors. Still, they note that factors not recorded in the surveys -- rather than chocolate consumption alone -- could have been responsible for some or all of the health benefits they observed.The study had some other important limitations. Most notably, the researchers did not determine whether the study participants ate dark, milk, or white chocolate.

Using one of the surveys administered during the study, the researchers estimated that 57 percent of the participants ate milk chocolate, 24 percent ate dark chocolate, and 2 percent ate white chocolate. This data, however, came from a subset of just under 1,600 participants, so they are merely estimates that may not have been borne out in the full study population.

Experts believe that natural compounds known as flavonoids (or flavonols), which appear to promote artery health and reduce inflammation, are responsible for the cardiovascular benefits that have been associated with chocolate consumption.

Flavonols are found in cocoa, and dark chocolate contains more cocoa than milk chocolate does.

"The benefits of chocolate come from flavonoids, and those are mainly found in dark chocolate, not Easter eggs, which are usually milk chocolate and have a lot of saturated fat," says Julia Zumpano, a registered clinical dietitian at the Cleveland Clinic, in Ohio. "I usually recommend less than one ounce of dark chocolate a day -- a tiny square -- for heart health," she adds. "The chocolate should be at least 70 percent cocoa with limited added sugar."

This study is merely the latest to point to the heart benefits of chocolate. In addition to lower blood pressure, cocoa consumption has been linked to improved blood vessel function, lower LDL (or bad cholesterol), and higher HDL (good cholesterol) in recent years.

Despite their findings, Buijsse and his colleagues caution that more research, namely randomized trials on the heart benefits of chocolate, is needed. Buijsse admits to being conservative about his own chocolate consumption.

"If I eat chocolate, which is not on a daily basis, I limit my intake to a small piece," he says.

(Health.com) -- Scientists have finally confirmed what the rest of us have suspected for years: Bacon, cheesecake, and other delicious yet fattening foods may be addictive.

A new study in rats suggests that high-fat, high-calorie foods affect the brain in much the same way as cocaine and heroin. When rats consume these foods in great enough quantities, it leads to compulsive eating habits that resemble drug addiction, the study found.

Doing drugs such as cocaine and eating too much junk food both gradually overload the so-called pleasure centers in the brain, according to Paul J. Kenny, Ph.D., an associate professor of molecular therapeutics at the Scripps Research Institute, in Jupiter, Florida. Eventually the pleasure centers "crash," and achieving the same pleasure--or even just feeling normal--requires increasing amounts of the drug or food, says Kenny, the lead author of the study.

"People know intuitively that there's more to [overeating] than just willpower," he says. "There's a system in the brain that's been turned on or over-activated, and that's driving [overeating] at some subconscious level."

In the study, published in the journal Nature Neuroscience, Kenny and his co-author studied three groups of lab rats for 40 days. One of the groups was fed regular rat food. A second was fed bacon, sausage, cheesecake, frosting, and other fattening, high-calorie foods--but only for one hour each day. The third group was allowed to pig out on the unhealthy foods for up to 23 hours a day.

Not surprisingly, the rats that gorged themselves on the human food quickly became obese. But their brains also changed. By monitoring implanted brain electrodes, the researchers found that the rats in the third group gradually developed a tolerance to the pleasure the food gave them and had to eat more to experience a high.