Contraction of front and side parts - as cells die off - was observed in some subjects in their thirties, but it was still not evident in some sixty­year­olds and seventy­year­olds.

　　Matsuzawa concluded from his tests that there is a simple remedy to the contraction normally associated with age - using the head.

　　The findings show in general terms that contraction of the brain begins sooner in people in the country than in the towns. Those least at risk, says Matsuzawa, are lawyers, followed by university professors and doctors. White collar workers doing routine work in government offices are, however, as likely to have shrinking brains as the farm workers, bus drivers and shop assistants.

　　Matsuzawa's findings show that thinking can prevent the brain from shrinking. Blood must circulate properly in the head to supply the fresh oxygen the brain cells need. "The best way to maintain good blood circulation is through using the brain，" he says, "Think hard and engage in conversation. Don't rely on pocket calculators."

　　语篇解读：一项研究表明多思考、多用脑会让人老得慢一些。

　　5．The team of doctors wanted to find out ________.

A．why certain people age sooner than others

B．how to make people live longer

　　 C．the size of certain people's brains

　　 D．which people are most intelligent

　　解析：选A　细节理解题。由第二段可知医生们想要弄清楚为什么一些人比其他人老得更快。

　　6．On what are their research findings based?

　　A．A survey of farmers in northern Japan.

　　B．Tests performed on a thousand old people.

　　C．The study of brain volumes of different people.

　　D．The latest development of computer technology.

　　解析：选C　细节理解题。由第三段"... he set about measuring brain volumes of a thousand people of different ages and varying occupations."可知选C。

　　7．The doctors' test shows that ________.

　　A．our brains shrink as we grow older

　　B．the front section of the brain does not shrink

　　C．sixty­year­olds have better brains than thirty­year­olds

　　D．some people's brains have contracted more than other people's

解析：选D　细节理解题。由倒数第二段"The findings show in general terms that contraction