If you want to stay young, sit down and have a good think. This is the research finding of

If you want to stay young, sit down and have a good think. This is the research finding of a team of Japanese doctors, who say that most of out brains are not getting enough exercise, and as a result, we are growing old unnecessarily soon.
Professor Taiju Matsuzawa wanted to find out why quite healthy farmers in northern Japan appeared to be losing their ability to think and reason at a rather early age, and how the speed of getting old could be slowed down.
With a team of researchers at Tokyo National University, he set about measuring brain sizes of a thousand people of different ages with different jobs.
Computer technology helped the researchers to get most exact measurements of the sizes of the front and side parts of the brain, which have something to do with thinking and feeling, and decide the human character. As we all know, the back part of the brain, which controls task like eating and breathing, does not contract(萎缩) with age.
Contraction of front and side parts, as cells(细胞) die off, was seen in some people in their thirties, but it was still not found in some sixty and seventy-year-olds.
Matsuzawa concluded from his tests that there is a simple way to prevent the contraction---using the head.
The findings show that contraction of the brain begins sooner in people in the country than those in the towns. Those with least possibility, says Matsuzawa, are lawyers, followed by university professors and doctors. White-collar workers doing the same work day after day in government offices are, however, as possible to have contracting brains as the farm workers, bus drivers and shop assistants.
【小题1】 The team of doctors wanted to find out     .A．at what point people grow live longer.B．how to make people live longerC．the size of certain people’s brains.D．which group of people are the busiest【小题2】Their research findings are based on     .cA．an examination of farmers in northern JapanB．using puter technologyC．examining the brain sizes of different peopleD．tests given a thousand old people【小题3】The doctor’s tests show that     .A．our brains contract as we grow olderB．one part of the brain does not contractC．sixty-year-olds have better brains than thirty-year-oldsD．contraction of the brain begins sooner in people in the country【小题4】 According to the article,      are growing mentally old earlier.A．engineersB．office clerksC．professorsD．researchers【小题5】The most possible conclusion of the article is that     .A．most of us should take more exerciseB．it’s better to live in the townsC．the brain contracts if it is not usedD．the more one uses his brain, the sooner he bees old.A