Acta Oto-Laryngologica
ISSN: 0001-6489 (Print) 1651-2251 (Online) Journal homepage: http://www.tandfonline.com/loi/ioto20
Human Sleep Modifications Induced By Urban Traffic Noise B. Bergamasco, P. Benna & M. Gilli To cite this article: B. Bergamasco, P. Benna & M. Gilli (1976) Human Sleep Modifications Induced By Urban Traffic Noise, Acta Oto-Laryngologica, 81:sup339, 33-36, DOI: 10.3109/00016487609124921 To link to this article: http://dx.doi.org/10.3109/00016487609124921
Published online: 08 Jul 2009.
Submit your article to this journal
Article views: 3
View related articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ioto20 Download by: [University of New England]
Date: 22 March 2016, At: 15:15
Acta Otolaryng Suppl 339: 33-36, 1976
HUMAN SLEEP MODIFICATIONS JNDUCED BY URBAN TRAFFIC NOISE B. Bergamasco, P. Benna, M. Gilli
Downloaded by [University of New England] at 15:15 22 March 2016
Froiii tlie
Depurtment of’ Audiology and the Nervous utid Mentul Diseuses Clitiic, University of’ Turin, Turin, Iialy
SCOPE OF THE RESEARCH
MATERIAL AND METHODS
In previous research, we examined the effects of noise on various cerebral electrophysiological parameters with the encephalon in waking state. As it is widely believed that noise is the major sleep-disturbance factor, we undertook a study of the modifications induced by road noise on human EEG during sleep, road noise being an element of stress which is becoming more and more important, especially in large towns. The literature, however, contains few reports by workers who have studied the way in which noise interferes i n this highly important factor in human homoeostasis. On the one hand, Kryter (1 970) has highlighted the importance of certain noise characteristics (its intensity, its unexpectedness, or the fact that it belongs to the subject’s normal habitat, its continuity in time or the intermittence of its source); on the other, Alexandre (1972 a, b) has demonstrated the importance of inherent factors within each individual. These vary with the stage of sleep and the subject’s age, sex, character and state of health. It is equally true, however, that to some extent the subject manages to adapt to greater or less noise in his environment: Schieber et al. (1968) have shown that the depth of sleep falls proportionally to the backgrounti noise against which the subject sleeps. It has also been noted that the more an organism is in need of sleep, the higher becomes its threshold to noise stimuli. This, however, does not belie the current belief that noise disturbs a person trying to sleep.
Our research into the effects of road noise on sleep was carried out with the assistance of five normal volunteers of both sexes and aged between 23 and 32. The road noise employed consisted of 3 recordings of night-time traffic made in 3 different points of Turin lasting 15 min eachwith intervals of 15 min silence. These were put on to 4 tapes of 90 min each to enable us to carry out experiments lasting 6 hours. The road noise data in terms of L,n and Ler, were as follows: N.
Mln.
L,dB
L,,dB
1
0-15 15-30 30-45
63.3 87.7 63.4 86.5 63.9 87.9
63.6 89.3 63.8 88.7 64.2 90.7
2 3 4 5 6
45-60 60-75 75-90
0
i dB
1.7 4.1
1.6 4.62 1.65 4.5
L,dB(A)
L,,dB(A)
oidB(A)
5317 74.9 54 71.6 54.2 75.4
54.7 76.9 54 74 54.2 77.7
1.6 4.3 0.6 4.2 0.86 4.45
The road noise was used with real intensity characteristics valued by means of a Bruel and Kjaer mod. 2209 phonometer, with mod. 1613 octave filter at the subject’s head. The tape was played on a Uher 4400, Report Stereo I C tape-recorder and put throug an Elit 815 audiometer into a free field from a speaker located half a metre from the subject’s head. The subject was laid on a normal bed in a darkened room of the EEG section of the Clinic of Nervous and Mental Diseases, University of Turin. Acru Otolaryng Suppl
33Y
34 G. Rossi
Downloaded by [University of New England] at 15:15 22 March 2016
Table I . Percentage values of the duration of the various stages qfsleep in 5 normirl subjects during administrution o f road noise, compared with the average duration values of sleep phases in the normal adult. Subiects
Aw.
Sleep adult G.P. M.A. R.G. C.F. C.P.
1 % 7.8 % 2 % 10.6% 21.5% 3.5 %
mean values in normal subjects 23 y. 26 y. 26 y. 32 y. 30 y.
I.st St.
6 %
11.5%
9.3 %
11.6% 14.6%
12.9%
Each subject began with a night of sleep during which noise was administered in the manner indicated in order to obviate those psychological problems which classically disturb the sleep of the normal adult (change of bed, environment, background noise). The following night, EEG, ECG and EOG were recorded using needle electrodes to permit subjects some motility during sleep. Before examining the results, it should be borne in mind that we did not compare sleep morphology during noise with the normal sleep morphology of the same subjects but with average statistical data, in spite of the fact that each individual has his own sleep modalities. This is because it was our intention to highlight the " acute " effects of noise with respect
2.nd St.
3.rd St.
4.th St
48 % 35.8 % 59.8 % 33.7% 38.8 % 51.6%
7 % 6.5 '%, 16.9 10.8% 16.9 % 7.9
15
%
9.8 'X 0.9 % 5.7 % 8.2% 6.2 %
REM St. 23 74 29.6 % 11.1
%
27.6 % 0 % 17.9 %
to an ideal functional situation. Nor did we investigate the adaptation modalities of the nervous system obliged to sleep in a noisy environment.
RESULTS The results showed quantitative and qualitative alterations to sleep (Table I). First of all, the arousal phase (including the waking period prior to going off to sleep as well as arousals during the night) was of greater duration percentage-wise than normal values, obviously meaning a reduction in total sleep duration in its various stages. The sleeping phase was much longer in all subjects, as may be seen in the percentage data relating to stage I although this, as already
Fig. I . Hypnogram of a normal subject during administration of road noise. Note the lengthening of the sleeping stage. Hypnograni substantially preserved. (white - silence; black noise). ~
Actu Otoluryn~rS i p [ ) [ 339
Downloaded by [University of New England] at 15:15 22 March 2016
Urhun t r u f i c noise 35
Fig. 2. Hypnogram of a subject during administration of road noise. Note the absence of the REM stage. (white = silence; black = noise).
Fig. 3. Hypnogram of a subject during administration of road noise. Note frcquent periods of light sleep and the short duration of REM and IV stages. (white - silence: black noise). ~
mentioned, takes in the numerous episodes of light sleep that occurred during the night. The duration of stage 11 was substantially the same while that of stage 111 was slightly increased, logically enough (this is the stage during which the " K complexes " occur, namely those bioelectric cortical potentials that would appear to be evoked by somatoaesthesic sensations and by external stimuli related to the state of marked neuronal hyperexcitability encountered i n this
stage of sleep). Alterations observed in stage IV were more marked (this is the stage of deep sleep during which the cortex produces large slow waves and loses its ability to respond to internal and external stimulation): the duration of stage IV was markedly reduced in all cases. The finding is of notable importance because this sleep stage is indispensable for CNS recuperation - like R E M sleep - as is shown by sleep deprivation data (West, 1967).
Downloaded by [University of New England] at 15:15 22 March 2016
36
G. Rossi
The length of REM sleep was not substantially changed compared to average values in three of our cases; in one case, the percentage of REM sleep was of short duration while another subject had no REM sleep at all. These latter two subjects enjoyed short percentage periods of IV sleep and high percentage periods of arousal (figs. 1 , 2, 3). It should be pointed out at this point that prior to EEG, our subjects were put through personality tests and those presenting the most marked REM stage changes were found by these tests to be of “anxietyintroversion ” type. Although not disconnected with the subject’s basic personality characteristics, these results still point to the gravity of the ‘‘ noise-sleep disturbance ” problem when it is considered that in our experimental situation, the night-time noise administered was that of “ normal ” roads at various points in Turin. CONCLUSIONS Our conclusions indicate that noise is a disturbing factor for the most delicate and de-
Acta Otoluryn~rSuppl 339
manding functions of the CNS in a high percentage of subjects and modifies the normal state of vigilance and particularly the regularity of sleep. With the present techiques, this may be observed objectively in those normal subjects who present some instability in emotion control mechanisms. We believe that in subjects where such control is disturbed (neurotics for instance) the effects are much more manifest and harmful and it is also likely that in such subjects noise plays a part in the development of mental disease symptomatology. “
”
REFERENCES Alexandre A . : Les effets du bruit sur le sommeil ( 1 . h partie). Nuisances et environnement, 3, 37, 1972 a. Alexandre A , : Les effets du bruit sur le sommeil (2.enie partie). Nuisances et environnement, 4, 43, 1972 b. Kryter K. D.: Effects of noise on man. Academic Press, New York-London, 1970. West L. Y .: Psychopathology produced by sleep deprivation. Sleep and altered states of consciousness. Williams and Wilkins, Baltimore, 1967. Schieber, J. P., Mery, J. et Huzet, A.: Etude analytique en laboratoire de I’influence du bruit sur le sommeil. Centre d’Efudes Bioclimafiques du CNRS de Strasbourg. Rapport, 1968.
ISSN: 0001-6489 (Print) 1651-2251 (Online) Journal homepage: http://www.tandfonline.com/loi/ioto20
Human Sleep Modifications Induced By Urban Traffic Noise B. Bergamasco, P. Benna & M. Gilli To cite this article: B. Bergamasco, P. Benna & M. Gilli (1976) Human Sleep Modifications Induced By Urban Traffic Noise, Acta Oto-Laryngologica, 81:sup339, 33-36, DOI: 10.3109/00016487609124921 To link to this article: http://dx.doi.org/10.3109/00016487609124921
Published online: 08 Jul 2009.
Submit your article to this journal
Article views: 3
View related articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ioto20 Download by: [University of New England]
Date: 22 March 2016, At: 15:15
Acta Otolaryng Suppl 339: 33-36, 1976
HUMAN SLEEP MODIFICATIONS JNDUCED BY URBAN TRAFFIC NOISE B. Bergamasco, P. Benna, M. Gilli
Downloaded by [University of New England] at 15:15 22 March 2016
Froiii tlie
Depurtment of’ Audiology and the Nervous utid Mentul Diseuses Clitiic, University of’ Turin, Turin, Iialy
SCOPE OF THE RESEARCH
MATERIAL AND METHODS
In previous research, we examined the effects of noise on various cerebral electrophysiological parameters with the encephalon in waking state. As it is widely believed that noise is the major sleep-disturbance factor, we undertook a study of the modifications induced by road noise on human EEG during sleep, road noise being an element of stress which is becoming more and more important, especially in large towns. The literature, however, contains few reports by workers who have studied the way in which noise interferes i n this highly important factor in human homoeostasis. On the one hand, Kryter (1 970) has highlighted the importance of certain noise characteristics (its intensity, its unexpectedness, or the fact that it belongs to the subject’s normal habitat, its continuity in time or the intermittence of its source); on the other, Alexandre (1972 a, b) has demonstrated the importance of inherent factors within each individual. These vary with the stage of sleep and the subject’s age, sex, character and state of health. It is equally true, however, that to some extent the subject manages to adapt to greater or less noise in his environment: Schieber et al. (1968) have shown that the depth of sleep falls proportionally to the backgrounti noise against which the subject sleeps. It has also been noted that the more an organism is in need of sleep, the higher becomes its threshold to noise stimuli. This, however, does not belie the current belief that noise disturbs a person trying to sleep.
Our research into the effects of road noise on sleep was carried out with the assistance of five normal volunteers of both sexes and aged between 23 and 32. The road noise employed consisted of 3 recordings of night-time traffic made in 3 different points of Turin lasting 15 min eachwith intervals of 15 min silence. These were put on to 4 tapes of 90 min each to enable us to carry out experiments lasting 6 hours. The road noise data in terms of L,n and Ler, were as follows: N.
Mln.
L,dB
L,,dB
1
0-15 15-30 30-45
63.3 87.7 63.4 86.5 63.9 87.9
63.6 89.3 63.8 88.7 64.2 90.7
2 3 4 5 6
45-60 60-75 75-90
0
i dB
1.7 4.1
1.6 4.62 1.65 4.5
L,dB(A)
L,,dB(A)
oidB(A)
5317 74.9 54 71.6 54.2 75.4
54.7 76.9 54 74 54.2 77.7
1.6 4.3 0.6 4.2 0.86 4.45
The road noise was used with real intensity characteristics valued by means of a Bruel and Kjaer mod. 2209 phonometer, with mod. 1613 octave filter at the subject’s head. The tape was played on a Uher 4400, Report Stereo I C tape-recorder and put throug an Elit 815 audiometer into a free field from a speaker located half a metre from the subject’s head. The subject was laid on a normal bed in a darkened room of the EEG section of the Clinic of Nervous and Mental Diseases, University of Turin. Acru Otolaryng Suppl
33Y
34 G. Rossi
Downloaded by [University of New England] at 15:15 22 March 2016
Table I . Percentage values of the duration of the various stages qfsleep in 5 normirl subjects during administrution o f road noise, compared with the average duration values of sleep phases in the normal adult. Subiects
Aw.
Sleep adult G.P. M.A. R.G. C.F. C.P.
1 % 7.8 % 2 % 10.6% 21.5% 3.5 %
mean values in normal subjects 23 y. 26 y. 26 y. 32 y. 30 y.
I.st St.
6 %
11.5%
9.3 %
11.6% 14.6%
12.9%
Each subject began with a night of sleep during which noise was administered in the manner indicated in order to obviate those psychological problems which classically disturb the sleep of the normal adult (change of bed, environment, background noise). The following night, EEG, ECG and EOG were recorded using needle electrodes to permit subjects some motility during sleep. Before examining the results, it should be borne in mind that we did not compare sleep morphology during noise with the normal sleep morphology of the same subjects but with average statistical data, in spite of the fact that each individual has his own sleep modalities. This is because it was our intention to highlight the " acute " effects of noise with respect
2.nd St.
3.rd St.
4.th St
48 % 35.8 % 59.8 % 33.7% 38.8 % 51.6%
7 % 6.5 '%, 16.9 10.8% 16.9 % 7.9
15
%
9.8 'X 0.9 % 5.7 % 8.2% 6.2 %
REM St. 23 74 29.6 % 11.1
%
27.6 % 0 % 17.9 %
to an ideal functional situation. Nor did we investigate the adaptation modalities of the nervous system obliged to sleep in a noisy environment.
RESULTS The results showed quantitative and qualitative alterations to sleep (Table I). First of all, the arousal phase (including the waking period prior to going off to sleep as well as arousals during the night) was of greater duration percentage-wise than normal values, obviously meaning a reduction in total sleep duration in its various stages. The sleeping phase was much longer in all subjects, as may be seen in the percentage data relating to stage I although this, as already
Fig. I . Hypnogram of a normal subject during administration of road noise. Note the lengthening of the sleeping stage. Hypnograni substantially preserved. (white - silence; black noise). ~
Actu Otoluryn~rS i p [ ) [ 339
Downloaded by [University of New England] at 15:15 22 March 2016
Urhun t r u f i c noise 35
Fig. 2. Hypnogram of a subject during administration of road noise. Note the absence of the REM stage. (white = silence; black = noise).
Fig. 3. Hypnogram of a subject during administration of road noise. Note frcquent periods of light sleep and the short duration of REM and IV stages. (white - silence: black noise). ~
mentioned, takes in the numerous episodes of light sleep that occurred during the night. The duration of stage 11 was substantially the same while that of stage 111 was slightly increased, logically enough (this is the stage during which the " K complexes " occur, namely those bioelectric cortical potentials that would appear to be evoked by somatoaesthesic sensations and by external stimuli related to the state of marked neuronal hyperexcitability encountered i n this
stage of sleep). Alterations observed in stage IV were more marked (this is the stage of deep sleep during which the cortex produces large slow waves and loses its ability to respond to internal and external stimulation): the duration of stage IV was markedly reduced in all cases. The finding is of notable importance because this sleep stage is indispensable for CNS recuperation - like R E M sleep - as is shown by sleep deprivation data (West, 1967).
Downloaded by [University of New England] at 15:15 22 March 2016
36
G. Rossi
The length of REM sleep was not substantially changed compared to average values in three of our cases; in one case, the percentage of REM sleep was of short duration while another subject had no REM sleep at all. These latter two subjects enjoyed short percentage periods of IV sleep and high percentage periods of arousal (figs. 1 , 2, 3). It should be pointed out at this point that prior to EEG, our subjects were put through personality tests and those presenting the most marked REM stage changes were found by these tests to be of “anxietyintroversion ” type. Although not disconnected with the subject’s basic personality characteristics, these results still point to the gravity of the ‘‘ noise-sleep disturbance ” problem when it is considered that in our experimental situation, the night-time noise administered was that of “ normal ” roads at various points in Turin. CONCLUSIONS Our conclusions indicate that noise is a disturbing factor for the most delicate and de-
Acta Otoluryn~rSuppl 339
manding functions of the CNS in a high percentage of subjects and modifies the normal state of vigilance and particularly the regularity of sleep. With the present techiques, this may be observed objectively in those normal subjects who present some instability in emotion control mechanisms. We believe that in subjects where such control is disturbed (neurotics for instance) the effects are much more manifest and harmful and it is also likely that in such subjects noise plays a part in the development of mental disease symptomatology. “
”
REFERENCES Alexandre A . : Les effets du bruit sur le sommeil ( 1 . h partie). Nuisances et environnement, 3, 37, 1972 a. Alexandre A , : Les effets du bruit sur le sommeil (2.enie partie). Nuisances et environnement, 4, 43, 1972 b. Kryter K. D.: Effects of noise on man. Academic Press, New York-London, 1970. West L. Y .: Psychopathology produced by sleep deprivation. Sleep and altered states of consciousness. Williams and Wilkins, Baltimore, 1967. Schieber, J. P., Mery, J. et Huzet, A.: Etude analytique en laboratoire de I’influence du bruit sur le sommeil. Centre d’Efudes Bioclimafiques du CNRS de Strasbourg. Rapport, 1968.
