1. wearing a seat belt saves lives; it reduces your chance of death or serious injury by more than half.
2. but it will be the driver’s responsibility to make sure that children under 14 do not ride in the front unless they are wearing a seat belt of some kind.
3. however，you do not have to wear a seat belt if you are reversing your vehicle； or you are making a local delivery or collection using a special vehicle； or if you have a valid medical certificate which excuses you from wearing it.
4. remember you may be taken to court for not doing so，and you may be fined if you cannot prove to the court that you have been excused from wearing it.
5. professor taiju matsuzawa wanted to find out why otherwise healthy farmers in northern japan appeared to be losing their ability to think and reason at a relatively early age，and how the process of ageing could he slowed down.
6. with a team of colleagues at tokyo national university，he set about measuring brain volumes of a thousand people of different ages and varying occupations.
7. computer technology enabled the researchers to obtain precise measurements of the volume of the front and side sections of the brain， which relate to intellect （智能） and emotion， and determine the human character.
8. 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 sixty and seventy-year-olds.
9. the findings show in general terms that contraction of the brain begins sooner in people in the country than in the towns.
10. white collar workers doing routine work in government offices are， however， as likely to have shrinking brains as the farm worker， bus driver and shop assistant.