UNIT 9
TEXT
Throughout the ages different ideas have been expressed about the working of the human brain. It is only recently, however, that science has begun to give us some idea of how the brain really works.
The Brain
The Most Powerful
Computer in the Universe
Man still has a lot to learn about the most powerful and complex part of his body -- the brain.
In ancient times men did not think that the brain was the centre of mental activity. Aristotle the philosopher of ancient Greece thought that the mind was based in the heart. It was not until the 18th century that man realised that the whole of the brain was involved in the workings of the mind.
During the 19th century scientists found that when certain parts of the brain were damaged men lost the ability to do certain things. And so, people thought that each part of the brain controlled a different activity. But modern research has found that this is not so. It is not easy to say exactly what each part of the brain does.
In the past 50 years there has been a great increase in the amount of research being done on the brain. Chemists and biologists have found that the way the brain works is far more complicated that they had thought. In fact many people believe that we are only now really starting to learn the truth about how the human brain works. The more scientists find out, the more questions they are unable to answer. For instance, chemists have found that over 100,000 chemical reactions take place in the brain every second. Mathematicians who have tried to use computers to copy the way the brain works have found that even using the latest electronic equipment they would have to build a computer which weighed over 10,000 kilos. Some recent research also suggests that we remember everything that happens to us. We may not be able to recall this information, but it is all stored in our brains.
Scientists hope that if we can discover how the brain works, the better use we will be able to put it to. For example, how do we learn language? Man differs most from all the other animals in his ability to learn and use language but we still do not know exactly how this is dine. Some children learn to speak and read and write when they are very young compared to average children. But scientists are not sure why this happens. They are trying to find out whether there is something about the way we teach language to children which in fact prevents children from learning sooner.
Earlier scientists thought that during a man's lifetime the power of his brain decreased. But it is now thought that this is not so. As long as the brain is given plenty of exercise it keeps its power. It has been found that an old person who has always been mentally active has a quicker mind than a young person who has done only physical work. It is now thought that the more work we give our brains, the more work they are able to do.
Other people now believe that we use only 1% of our brains' full potential. They say that the only limit on the power of the brain is the limit of what we think is possible. This is probably because of the way we are taught as children. When we first start learning to use our minds we are told what to do, for example, to remember certain facts, but we are not taught how our memory works and how to make that best use of it. We are told to make noted hut we are not taught how our brains accept information and which is the best way to organise the information we want our brains to accept.
This century man has made many discoveries about the universe -- the world outside himself. But he has also started to look into the workings of that other universe which is inside himself -- the human brain.
NEW WORDS
computer
n. machine that stores information and works out answers 计算机
universe
n. 宇宙
complex
a. difficult to understand or explain 错综复杂的，难懂的
ancient
a. in or of times long ago 古代的;古老的
philosopher
n. 哲学家
philosophy
n. 哲学
involve
vt. cause to become connected or concerned 使卷入
working
n. (usu. pl.) operation; action 运转，运行，活动
ability
n. 能力
exactly
ad. with complete connected or concerned 确切地;精确地
amount
n. 数量，数额
chemist
n. one who studies and understands chemistry 化学家
biologist
n. one who studies the life of animals and plants 生物学家
biology
n. 生物学
complicated
n. difficult to understand, complex 难懂的;复杂的
chemical
a. of chemistry
unable
a. not able
reaction
n. 反应
mathematician
n. one who studies and understands mathematics 数学家
equip
n. 设备，装置
kilo = kilogram
公斤，千克
recent
a. done or made not long ago 近来的
recall
vt. remember 记得;回忆起
differ
vi. be different (from)
mentally
ad. 智力上，脑力上
physical
a. of the body; of matter; of the science of physics 身体的;物质的;物理学的
potential
n. 潜力
limit
n. 局限，限度
PHRASES & EXPRESSIONS
put...to (good) use
use (in a profitable) (好好)利用
differ from
be dissimilar to 与...不同
compared to / with
in comparison with 与...相比
make notes
take notes 记笔记
look into
examine 调查，观察
PROPER NAMES
Aristotle
亚里士多德
Greece
希腊
