Saturday, September 23, 2006



BRAIN EXCERCISE?

The giant Nintendo store in Manhattan was swarming with silver-haired citizens and their grandchildren. The elders, gathered on a recent Saturday, weren't there to spoil the kids, however. Nintendo was hosting a video game competition to determine the "Coolest Grandparent," and the aging gamers in the store were competing for a Nintendo DS handheld game player. They weren't playing Super Mario Bros. either, but a product called Brain Age, a mind challenger targeted at one of the fastest-growing segments of the game market: people over 40 worried about losing their mental edge.

Meanwhile, at The Hallmark retirement community in Chicago, 16 residents just completed a complex memory training program developed by neuroscientist Michael Merzenich of the University of California at San Francisco. While Brain Age advertises that it can "train your brain in minutes a day," the Brain Fitness Program, marketed by Merzenich's Posit Science Corp., is a computer-based set of exercises that a user must sit down with an hour a day for eight weeks.

Posit executives are emphatic that their programs are not video games, and the company published a scientific study in August that lays out the memory-enhancing bona fides of Brain Fitness. Hallmark resident Sadelle T. Greenblatt, age 85, is already convinced. After going through the Brain Fitness course she says "my memory, I think, is in some ways better. When I play bridge now, I can always remember if all the trumps are out."

Nintendo and Posit are both profiting from the memory decline that is one of the more disquieting markers of aging. As baby boomers march toward senior citizenship, hiding their mental age may prove as important to them as concealing their gray hair. Nintendo says its recent emphasis on what it calls "gray gamers" already pushed second-quarter profits up eightfold.

The industry must face down one potentially large obstacle, however. There is no empirical proof that brain teasers, crossword puzzles, or any of the other mental exercises out there will slow mental decline, or thwart Alzheimer's disease.

Efforts to improve the aging mind are one of the more contentious areas of science. Shelf after shelf of books call on seniors to "use it or lose it," arguing that brain activity will prevent cognitive losses. So far, it's only a catchphrase. Last spring, University of Virginia neuroscientist Timothy A. Salthouse analyzed a large number of studies meant to show that mental challenges arrest brain decline. He found none that proved its thesis. So far, he concluded, "the mental-exercise hypothesis is more of an optimistic hope than an empirical reality."

"LITTLE EVIDENCE"

Salthouse discovered that most brain-training studies suffer from a "chicken or the egg" problem. It could be that people who performed well in studies involving mental exercises were more mentally agile to begin with. It is true that practice makes perfect, says Matthew L. Shapiro, a neuroscientist at Mount Sinai School of Medicine in New York. "The more you try to remember, the better your skill at remembering." Still, he says there is little evidence that those improvements will lead to overall mental improvement, and a brain disease "will ultimately overwhelm any efforts to better your skills."

The most skillful game-playing grandparents at the Nintendo event were proof that practice pays off. Lynn Lipton, a 66-year-old retired teacher from Poughkeepsie, N.Y., says she has been an avid video gamer since Pong was introduced some 30 years ago. "I don't have the data to prove that it helps my memory, but I know it helps me to read faster. It keeps me sharp," she says.

Not everyone can make that claim at 66, which is why brain training is getting so much attention. The human brain reaches its maximum weight by the age of 20 and then slowly starts shrinking. By age 50 or so memory formation usually slows down, and by 70 some 12% of the population suffers from mild cognitive impairment (MCI), characterized by frequent short-term memory lapses. People with MCI are three to four times more likely than their peers to develop Alzheimer's disease.

For decades, researchers thought that little could be done once the brain started to decline. But in the early 1990s Merzenich and others discovered that the brain remains plastic throughout life. With training, it can be rewired to learn new skills. From this discovery grew the belief -- now an industry -- that the aging brain can be taught to be young again.

Nintendo is quick to disavow any scientific claims for its Brain Age games, which cost $19.95 each. "We're in the entertainment business," says Perrin Kaplan, head of marketing for Nintendo's U.S. operations. But Nintendo does boast that Brain Age was developed with the help of Dr. Ryuta Kawashima, a respected Japanese neuroscientist whose face pops up at the start of every game. Kawashima believes brains can be kept young and nimble through the rapid repetition of simple mental challenges. The game is wildly popular in Japan, and 4 million copies have been sold worldwide since Brain Age was introduced 15 months ago.

Posit, founded by Merzenich in 2003, is all about the science. He lends the company plenty of scientific street cred; he made some of the key early findings about brain plasticity, helped pioneer cochlear ear implants, and developed well-regarded training programs for children with learning disabilities. He says his $395 Brain Fitness program is grounded in hard data.

This summer Posit released two studies that Merzenich says prove its worth. One, involving 182 healthy people 60 and over, assigned half the group to Posit's brain exercises for eight weeks. The rest were asked only to watch educational DVDs. The researchers found that 93% of the Brain Fitness group significantly improved their memory function, while the control group did not.

In a second study released this summer, Posit's program was tried on 45 people diagnosed with MCI. PET scans of the brains of 15 participants were taken before and after the study. There was some evidence of memory gains in the Brain Fitness group, and the PET scans revealed a decline in brain activity in those who did not use the brain exercises. Brain activity held steady for the rest. "We've seen 80-year-old people improve from being sluggish and slow to having the mental performance level of a 35-year-old," says Merzenich.

Whether these people will be able to stave off further cognitive decline remains to be proven. Salthouse, at the end of his paper debunking such efforts, wrote that there's no harm in trying. Even if there is no beneficial evidence, he wrote, engagement in such mentally demanding activities at least serves as proof of existence: "If you can still do it, then you know that you have not yet lost it."

Source





The latest wonder food: "An alternative to white sugar that is about to become more widely available could help slimmers to lose weight. Agave nectar, a honey-like liquid derived from the same plant as tequila, is 25 per cent sweeter than sugar. More importantly, it helps to burn rather than store fat and is thought to reduce the craving for sweet foods. Its high fruit sugar content is absorbed by the body more slowly than white sugar, and does not need insulin to break it down. Agave nectar, which can be used in tea and coffee and to bake with, is usually sold in health food shops but Tesco is about to become the first big supermarket chain to stock it." [We'll be hearing that it gives you either cancer or heart attacks in a few years time]


Surgery hope for paralysed: "A new treatment to repair damaged nerves could help thousands of patients regain movement in their arms and legs. Using a finely woven plastic tube, surgeons will regrow and reconnect severed nerves in road and work accident victims. The neural prosthesis is attached to the ends of the damaged nerve and acts as a scaffold to aid repair. Victorian doctors say the advanced surgical technique is more effective than nerve grafts and will restore sensation in the limbs of victims. St Vincent's Hospital neurosurgeon Assoc Prof Michael Murphy said the device was a vast improvement. "You can't stretch severed nerves," he said. "You can do a graft, taking nerves from elsewhere in the body, but the end result is poor. "If the tubular scaffold works, it will speed up repair and improve the outcome." Chemicals in the polymer tube accelerate regrowth of nerve cells, allowing the nerve to grow up to 4mm a day."

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Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.


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