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Children and noise
MAGNITUDE AND EFFECTS OF SOUND
COMMON EXAMPLE
dBA EFFECT
Breathing
Conversation at home
Freeway traffic (15 m), vacuum cleaner, noisy
party
Average factory, train (at 15 m)
Jet take-off (at 305 m), motorcycle
Thunderclap, textile loom, chain saw, siren,
rock concert
Toy cap pistol, Jet takeoff (at 25 m), firecracker
0-10 Hearing threshold
50
Quiet
Annoying, intrusive, interferes with
70
phone use
Possible hearing damage
80
100 Damage if over 1 minute
120
Human pain threshold
150
Eardrum rupture
VULNERABILITY OF CHILDREN Why might children be more
susceptible to noise effects?
 � Possible increased risk due to immaturity Increased cochlear
susceptibility?
 In utero
 Animal data studies
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� Critical periods in relation to learning
� Lack of developed coping repertoires
� Vulnerable tasks \ Vulnerable settings (schools, home,
streets)
What might be the implications of noise effects?
� Lifelong impairment of learning and education � Short-term deficit
followed by adaptation
� Non intentional lesions
FROM EXCESS NOISE EXPOSURE
�Direct ear damage
• Noise induced hearing loss
• Noise induced threshold shift
�Indirect adverse effects • Physiological effects
• Psychological effects
�Impaired cognition
PSYCHOLOGICAL DAMAGE
� Exposure to moderate level of noise can cause
• Psychological stress
• Annoyance, interference with activity, isolation
• Headache, tiredness and irritability; may impair intellectual function and performance of complex tasks
� Exposure to intense level of noise can
• Cause personality changes and aggressive/violent reactions
• Reduce ability to cope
• Alter work performance and intellectual function
• May cause muscle spasm and also break a bone (when combined with strong vibration) •Sleep
disturbance
•Changes in mental health.
� Exposure to sudden, unexpected noise can cause • Startle reaction with stress responses
• Cause non intentional injuries
INDIRECT ADVERSE EFFECTS
�Stress-related somatic effects • Stress hormone
• Blood pressure
• Muscle spasm
�Psychological effects • Annoyance / Isolation • Sleep disturbance
• Mental health
�Cognitive effects
• Reading, concentration, memory, attention .
IMPAIRED COGNITIVE FUNCTION
Chronic noise exposure impairs cognitive function

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Reading comprehension
Long term memory
� Dose-response relationships
• Supported by both laboratory and field studies
� Study of possible mechanisms and noise reduction interventions

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Tuning out of attention / concentration
Impairment of auditory discrimination
RAILWAY NOISE AND READING SCORES
� Reading scores compared between classes in same school � Exposed/not
exposed to railway noise
� No selection of children into classes
� Poorer performance on achievement test on noisy side � Measuring
reading age 3-4 months behind on noisy side .
IN PRE-SCHOOL AND SCHOOL-AGED CHILDREN
EFFECTS OF NOISE � Hearing impairment
• In isolated cases by toys or equipment � Sleep
disturbances
• Earlier responses than adults (EEG awakenings) � Somatic effects
• Blood pressure and stress hormones
� Psycho-social effects
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No studies on behaviour with high environmental noise levels
Cognitive tasks are impaired, like reading, long term memory, attention and
motivation
� Vocal nodule’ “
Bronzaft, A.L. and McCarthy, D.P. (1975) The effect of elevated train noise on
reading ability. Environment and Behaviour, 7(4), “( A 2x2x2 analysis of variance
performed on the word knowledge and reading comprehension scores of the children in the matched
classes of the 1974 academic year yielded a significant main effect for location( F= 7.270,df= 1,57,p<
.01). Students on the noisy side of the school building did more poorly on the achievement tests than
those on the quiet side of the building (see Table 1).
Finding a significant relationship between train noise and depressed reading scores
tends to support the Deutsch (1964) and Cohen et al. (1973) hypothesis which states
that low reading achievement may be related to exposure to noise
interference through the mediation of impaired auditory dis-crimination. Their
speculation that difficulty in learning how to read may be related to the tendency of a
child reared (or in this case, taught) in a noisy environment to block out indiscriminately all sound, whether relevant speech cues or not, is one plausible explanation of
the present finding.
Since Stempler (1973) reported that at least 11% of classroom teaching time is lost
daily because of passing trains, it is possible that lower test scores on the noisy side of
the school building may be the result of lost teaching time.”
Glass and Singer (1972a), through an extensive survey of previous noise research and their
own studies on noise adaptation, found that, following exposure to unpredictable and
uncontrollable high-intensity noise, the often reported after- effects were: degradation in
quality of task performance, lowered frustration tolerance, and impaired ability to resolve
cognitive conflicted,
Shield,B. and Dockrell, J. (2002), The effects of environmental noise on child
academic attainments. Proc. Institute of Acoustics 24(6).
Shield, B., Dockrell, J., Asker R. and Tachmatzidis, I. (2002) The effects of noise on
the attainments and cognitive development of primary school children. Final report
for Department of Health and DETR.
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