Test4

READING PASSAGE 3
You should spend about 20 minutes on Questions 27-40, which are based on Reading Passage 3
below.

EFFECTS OF NOISE
In general, it is plausible to suppose that we should prefer peace and quiet to noise. And
yet most of us have had the experience of having to adjust to sleeping in the mountains or
the countryside because it was initially 'too quiet', an experience that suggests that
humans are capable of adapting to a wide range of noise levels. Research supports this
view. For example, Glass and Singer (1972) exposed people to short bursts of very loud
noise and then measured their ability to work out problems and their physiological
reactions to the noise. The noise was quite disruptive at first, but after about four minutes
the subjects were doing just as well on their tasks as control subjects who were not exposed
to noise. Their physiological arousal also declined quickly to the same levels as those of
the control subjects.
But there are limits to adaptation and loud noise becomes more troublesome if the person
is required to concentrate on more than one task. For example, high noise levels interfered
with the performance of subjects who were required to monitor three dials at a time, a
task not unlike that of an aeroplane pilot or an air-traffic controller (Broad bent, 1957).
Similarly, noise did not affect a subject's ability to track a moving line with a steering
wheel, but it did interfere with the subject's ability to repeat numbers while tracking
(Finkelman and Glass, 1970).
Probably the most significant finding from research on noise is that its predictability is
more important than how loud it is. We are much more able to 'tune out' chronic
background noise, even if it is quite loud, than to work under circumstances with
unexpected intrusions of noise. In the Glass and Singer study, in which subjects were
exposed to bursts of noise as they worked on a task, some subjects heard loud bursts and
others heard soft bursts. For some subjects, the bursts were spaced exactly one minute
apart (predictable noise); others heard the same amount of noise overall, but the bursts

Loud noise 40.1 31.8 35.9

Soft noise 36.7 27.4 32.1

Average 38.4 29.6

Table I: Proofreading Errol"s and Noise

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 Reading

occurred at random intervals (unpredictable noise). Subjects reported finding the

predictable and unpredictable noise equally annoying, and all subjects performed at about
the same level during the noise portion of the experiment. But the different noise
conditions had quite different after-effects when the subjects were required to proofread
written material under conditions of no noise. As shown in Table I the unpredictable
noise produced more errors in the later proofreading task than predictable noise; and soft ,
unpredictable noise actually produced slightly more errors on this task than the loud,
predictable noise.
Apparently, unpredictable noise produces more fatigue than predictable noise, but it takes
a while for this fatigue to take its toll on performance.
Predictability is not the only variable that reduces or eliminates the negative effects of
noise. Another is control. If the individual knows that he or she can control the noise, this
seems to eliminate both its negative effects at the time and its after-effects. This is true even
if the individual never actually exercises his or her option to turn the noise off (Glass and
Singer, 1972). Just the knowledge that one has control is sufficient.
The studies discussed so far exposed people to noise for only short periods and only
transient effects were studied. But the major worry about noisy environments is that living
day after day with chronic noise may produce serious, lasting effects. One study, suggesting
that this worry is a realistic one, compared elementary school pupils who attended schools
near Los Angeles's busiest airport with students who attended schools in quiet
neighbourhoods (Cohen et al. , 1980). It was found that children from the noisy schools
had higher blood pressure and were more easily distracted than those who attended the
quiet schools. Moreover, there was no evidence of adaptability to the noise. In fact, the
longer the children had attended the noisy schools, the more distractible they became. The
effects also seem to be long lasting. A follow-up study showed that children who were
moved to less noisy classrooms still showed greater distractibility one year later than
students who had always been in the quiet schools (Cohen et al, 1981 ). It should be noted
that the two groups of children had been carefully matched by the investigators so that
they were comparable in age, ethnicity, race, and social class.

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Test 4

Questions 27-29

Choose the correct letter, A, B, Cor D.

Write the correct letter in boxes 27-29 on your answer sheet.

27 The writer suggests that people may have difficulty sleeping in the mountains because
A humans do not prefer peace and quiet to noise.
B they may be exposed to short bursts of very strange sounds.
C humans prefer to hear a certain amount of noise while they sleep.
D they may have adapted to a higher noise level in the city.
28 In noise experiments, Glass and Singer found that
A problem-solving is much easier under quiet conditions.
B physiological arousal prevents the ability to work.
C bursts of noise do not seriously disrupt problem-solving in the long term.
D the physiological arousal of control subjects declined quickly.
29 Researchers discovered that high noise levels are not likely to interfere with the
A successful performance of a single task.
B tasks of pilots or air traffic controllers.
C ability to repeat numbers while tracking moving lines.
D ability to monitor three dials at once.

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 Reading

Questions 30-34

Complete the summary using the list of words and phrases, A-J, below.

Write the correct letter, A-J, in boxes 30-34 on your answer sheet.

NB You may use any letter more than once.

Glass and Singer (1972) showed that situations in which there is intense noise have
less effect on performance than circumstances in which 30 .......... .. ............ noise
occurs. Subjects were divided into groups to perform a task. Some heard loud bursts
of noise, others soft. For some subjects, the noise was predictable, while for others its
occurrence was random. All groups were exposed to 31 ................ .... .... noise. The
predictable noise group 32 ............ ............ the unpredictable noise group on this task.
In the second part of the experiment, the four groups were given a proofreading task
to complete under conditions of no noise. They were required to check written material
for errors. The group which had been exposed to unpredictable noise 33 .......... ........ .. .. ..
the group which had been exposed to predictable noise. The group which had been
exposed to loud predictable noise performed better than those who had heard soft,
unpredictable bursts. The results suggest that 34 ...... .................. noise.' produces
fatigue but that this manifests itself later.

A no control over
B unexpected
C intense
D the same amount of
E performed better than
F performed at about the same level as
G no
H showed more irritation than
I made more mistakes than
J different types of

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Test4

Questions 35-40

Look at the following statements (Questions 35-40) and the list of researchers below.

Match each statement with the correct researcher( s), A-E.

Write the correct letter, A-E, in boxes 35-40 on your answer sheet.

NB You may use any letter more than once.

35 Subjects exposed to noise find it difficult at first to concentrate on problem-solving

tasks.
36 Long-term exposure to noise can produce changes in behaviour which can still be
observed a year later.
37 The problems associated with exposure to noise do not arise if the subject knows they
can make it stop.
38 Exposure to high-pitched noise results in more errors than exposure to low-pitched
noise.
39 Subjects find it difficult to perform three tasks at the same time when exposed to noise.
40 Noise affects a subject's capacity to repeat numbers while carrying out another task.

List of Researchers
A Glass and Singer
B Broadbent
C Finkelman and Glass
D Cohen et al.
E None of the above

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