Health & Science

It’s possible to get smarter

Intelligence has long been viewed by scientists as a stable trait: Either you’re smart or you’re not, and nothing you do can change that. But a new study has showed that the brain is like a muscle, and will get more powerful with the right kind of daily exercise. Scientists measured the IQs of 70 volunteers, then put them through a brain “boot camp‚” consisting of memory tasks that increased in difficulty as the subjects became more proficient. After 19 days of exercising their memories and solving puzzles, the volunteers’ IQs were retested, and the results were striking. Every single participant made significant gains in “fluid intelligence‚” the ability to solve problems, use abstract reasoning, and be quick on their feet. The longer people trained, the higher their scores rose. “Intelligence has always been considered principally an immutable inherited trait,” study co-author Susanne Jaeggi tells The New York Times. This study “definitely challenges the old opinions.”

The myth of the ‘green fairy’

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Absinthe, a green-colored, anise-flavored liquor once favored by Parisian artists and bohemians, was banned from the U.S. for decades, based on its reputation for causing wild hallucinations. It turns out that absinthe isn’t all it’s cracked up to be. A new study of both recently distilled absinthe and samples from antique bottles dating back a century found no chemicals capable of hallucinogenic effects, says LiveScience. A compound called thujone had been believed to have caused the drug-like effects, but the antique samples disproved this myth. If absinthe drinkers suffered dementia and death, the researchers said, it was because they drank large quantities of the 140-proof liquor daily, and had become alcoholics.

Restoring sight to the blind

An experimental gene-therapy technique has given partial sight to three legally blind people. Researchers packaged a light-sensitivity gene inside a harmless virus, then injected the virus directly into the eyes of three subjects, all of whom had very limited vision due to congenital defects. Just two weeks after the injections, the patients were reporting better sight: One was able to read three extra lines on a vision chart, and another was able to navigate an obstacle course. “All three subjects are asking if they can have their other eye injected,” study author Katherine High tells the Los Angeles Times. “That’s a pretty good indicator of effectiveness.” Gene therapy is a controversial field, known for alternating successes and dramatic failures that have resulted in the deaths of some patients. So far, the eye experiment has produced no significant side effects, and it offers a glimmer of hope to hundreds of thousands of people blinded by macular degeneration and other retinal disorders. “This is a really great advance,” says geneticist Stephen Rose. “This has changed the landscape for patients.”

How not to teach math

A train leaves New York and heads south at 40 miles per hour, while a second train pulls out of Washington, D.C., heading north at 55 miles per hour. If you just groaned, it’s because you remember these kinds of “helpful” real-world examples from math class, which generations of teachers and textbooks have offered in the belief that they make abstract math easier. But a new study says that these stand-ins just make math more difficult. When teachers use a paragraph-long problem like the classic two-trains scenario, “students only learn how to solve the problem with the trains,” study author Jennifer Kaminski tells LiveScience. “If students are later given a problem using the same mathematical principles, but about rising water levels instead of trains, that knowledge just doesn’t seem to transfer.” Students learn better, says researcher Vladimir Sloutsky, when they’re offered the concepts and equations in their natural, abstract form, undiluted by stories and objects. Once kids understand the math, he says, story problems are great for “testing what was learned. But they are bad instruments for teaching.”

Craving the taste of coal

Pregnant women today are more likely to report food cravings than were their mothers. A new survey of more than 2,000 women found that 75 percent of pregnant women today say they experience strong desires for particular foods, compared to 30 percent five decades ago. As usual, foods such as chocolate, ice cream with pickles, and peanut butter topped the list. But the survey also turned up strange desires to eat such nonfood items as dirt, chalk, and laundry soap. Of those women surveyed who reported unusual cravings, 17 percent fantasized about chewing on coal and 9 percent wanted to eat toothpaste. The cause of the increase in cravings is not known, but pregnancy nutrition specialist Fiona Ford tells BBCnews.com that it may be the result of modern moms’ exposure to a much wider variety of foods and textures. Their previous experience with such textures and tastes may prime them to crave something similar when pregnancy stirs up their hormones. Ford recommends chewing ice as a way to satisfy a craving for texture, “rather than chewing plaster off the walls or chewing match heads, or some of the other things we have had.”