Building a Better Brain

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Human brain works a lot like a muscle - the harder you use it, the more it grows. Although scientists had long believed the brain's circuitry was hard-wired by adolescence and inflexible in adulthood, its newly discovered ability to change and adapt is apparently with us well into old age. Best of all, this research has opened up an exciting world of possibilities for treating strokes and head injuries - and warding off Alzheimer's disease.

The party last year was as rowdy as it gets in a convent. Celebrating her 100th birthday, Sister Regina Mergens discarded her habit in favour of a daring red gown, downed two glasses of champagne and proclaimed her intention to live to 102. She didn't quite make it. Now, at vespers on a March afternoon in Mankato, MN, dozens of nuns file past the open casket where Mergens, 101 lies, rosary beads in her hands.

Concealed from view is an incision in the back of Mergen's head through which her brain has been removed. Mergens and nearly 700 elderly sisters in her order are the largest group of brain donors in the world. By examining these nuns, as well as thousands of stroke victims, amputees and people with brain injuries, researchers are living up to the promise of a presidential proclamation that the 1990's be the Decade of the Brain. Scientists are beginning to understand that the brain has a remarkable capacity to change and grow, even into old age, and that individuals have some control over how healthy and alert their brains remain as the years go by. The Sisters of Mankato, for example, lead an intellectually challenging life, and recent research suggests that stimulating the mind with mental exercise may cause brain cells, called neurons, to branch wildly. The branching causes millions of additional connections, or synapses, between brain cells. Think of it, says Arnold Scheibel, director of UCLA's Brain Research Institute, as a computer with a bigger memory board: "You can do more things more quickly."

The capacity of the brain to change offers a new hope for preventing and treating brain diseases. It helps to explain why some people can:

• delay the onset of Alzheimer's disease symptoms for years. Studies show that the more educated a person is, the less likely he or she is to show symptoms of the disease. The reason: Intellectual activity develops brain tissue that compensates for tissue damaged by the disease.
• make a better recovery from strokes. Research indicates that even when areas of the brain are permanently damaged by stroke, new message routes can be created to get around the roadblock or to resume the function of that area.

New knowledge about the brain may be received from the obscure convent in Minnesota. Mankato is the site of the northwest headquarters of the School Sisters of Notre Dame, where a long life is normal. In part because the nuns of this order don't drink much, smoke or die in childbirth, they live to an average age of 85, and many live far beyond that. Of the 150 retired nuns residing in this real-life Cocoon, 25 are older than 90.

Дата добавления: 2014-12-27