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Lesson 25 |
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Non-auditory effects of noise |
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What conclusion does the author draw about noise and health in this piece? |
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Many people in industry and the Services, |
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who have practical experience of noise, |
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regard any investigation of this question as a waste of time; |
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they are not prepared even to admit the possibility that noise affects people. |
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On the other hand, |
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those who dislike noise will sometimes use most inadequate evidence |
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to support their pleas for a quieter society. |
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This is a pity, because noise abatement really is a good cause, |
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and it is likely to be discredited if it gets to be associated with bad science. |
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One allegation often made is that noise produces mental illness. |
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A recent article in a weekly newspaper, for instance, |
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was headed with a striking illustration of a lady in a state of considerable distress, |
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with the caption 'She was yet another victim, reduced to a screaming wreck'. |
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On turning eagerly to the text, one learns that the lady was a typist |
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who found the sound of office typewriters worried her more and more |
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until eventually she had to go into a mental hospital. |
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Now the snag in this sort of anecdote is of course |
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that one cannot distinguish cause and effect. |
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Was the noise a cause of the illness, |
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or were the complaints about noise merely a symptom? |
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Another patient might equally well complain |
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that her neighbours were combining to slander her and persecute her, |
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and yet one might be cautious about believing this statement. |
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What is needed in the case of noise |
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is a study of large numbers of people living under noisy conditions, |
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to discover whether they are mentally ill more often than other people are. |
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Some time ago the United States Navy, for instance, |
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examined a very large number of men working on aircraft carriers: |
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the study was known as Project Anehin. |
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It can be unpleasant to live even several miles from an aerodrome; |
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if you think what it must be like |
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to share the deck of a ship with several squadrons of jet aircraft, |
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you will realize that a modern navy is a good place to study noise. |
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But neither psychiatric interviews nor objective tests |
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were able to show any effects upon these American sailors. |
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This result merely confirms earlier American and British studies: |
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if there is any effect of noise upon mental health, |
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it must be so small that present methods of psychiatric diagnosis cannot find it. |
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That does not prove that it does not exist; but it does mean |
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that noise is less dangerous than, say being brought up in an orphanage |
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-- which really is a mental health hazard. |