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University of Central Florida Retrospective Theses and Dissertations Masters Thesis (Open Access) Effects of Noise on Blood Pressure and Heart Rate in Deaf Adults 1974 Albert R. Bartee University of Central Florida Find similar works at: http://stars.library.ucf.edu/rtd University of Central Florida Libraries http://library.ucf.edu Part of the Social and Behavioral Sciences Commons STARS Citation Bartee, Albert R., "Effects of Noise on Blood Pressure and Heart Rate in Deaf Adults" (1974). Retrospective Theses and Dissertations. 87. http://stars.library.ucf.edu/rtd/87 This Masters Thesis (Open Access) is brought to you for free and open access by STARS. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of STARS. For more information, please contact [email protected]. EFFECTS OF NOISE ON BLOOD PRESSURE A1D HEART RATE IN DEAF ADULTS BY ALBERT ROSS BARTEE THESIS Submitted in partial fulfill ment of th e requirements for the degree of Master of Arts in the Graduate Studi es Program of Florida Technological Univer sity Orlando, Florida 1974 ACKNOWLEDGMENT I would like to express appreciation to all those individuals without whose help this study would not have become a reality. To my Committee Chairman and friend, Dr. Thomas A. Mullin, whose professionalism, attention to detail and constant encouragement has made my experience at F.T.U., both enriching and pleasurable. MY gratitude is also extended to other members of my Committee: Dr. Robert Arnold and Dr. Thomas MOrgan and a sincere thank you to Dr. Albert Pryor, who although not an official member of my Committee gave unselfishly of his time and expertise. Others who have helped this thesis become a reality are Dr. Raymond Buchanan, Dr. David Barr, and Dr. Charles Dziuban and Mrs. Janice FitzGerald. Finally my appreciation is extended to my loving wife, Tiny, for her patience and confidence and to my son Michael, who gave of his time. ii to my mother and father in appreciation of their never ending faith and everlasting encouragement this thesis is affectionately dedicated iii TABLE OF CONTENTS Page LIST OF TABLES • • • • • • • • • • • • • • • • • • • • • • • • • • LIST OF ILLUSTRATIONS • • • • • • • • • • • • • • • • • • • • • • • INrRODUCTION AND RATIONALE • • • • • • • • • • • • • • • • • • • • • The Auditory Mechanism • • • • • • • • • • • • The Effects of Noise • • • • • • • • • • • • • Normal Hearing Individuals • • • • • • • • • • Deaf Individuals • • • • • • • • • • • • • • METHODOLOGY • • • • • • • • • • • • • • • • • • • • 6 • • • • • • • • • • • • • • • • • • • ............. .............. ~ • • 9 • • 10 10 • • • • • • • • • •• • • • • • •• • • • • • • • 12 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Heart Rate • • • • • • • • • • • • • • • • • • • • • • • • • Systolic Blood Pressure • • • • • • • • • • • • • • • • • • Diastolic Blood Pressure • • • • • • • • • • • • • • • • • • DISCUSSION • • • 0 • 8 . 8 8 8 8 8 8 9 0 . . . .- . . 1 2 3 4 5 Test Site • • • • • • • • • • Subjects • • • • • • • • • Instrumentation • • • • • • • Rooms • • • • • • • • • Pure Tones • • • • • • • Calibration • • • • • • • Stimulus Presentation • • • Blood Pressure and Heart Rate Stimulus Materials • • • • • Procedures • • • • • • • RESULTS vii • • • • • • • • • • • • • • • • 0 STATEMENT OF THE PROBLEM vi • • • • • • • • • • • • • • • • • • • • • • • • • 12 17 • 25 • Heart Rate • • • • • • • • • • • • • • • • • • • • • • • • • • Systolic Blood Pressure • • • • • • • • • • • • • • • • • • • • Diastolic Blood Pressure • • • • • • • • • • • • • • • • • • • • Pathology • • • • • • • • • • • • • • • • • • • • • • • • • Implications for Further Research • • • • • • • • • • • • • • iv 12 • • • • • 25 26 26 28 28 Page S~RY • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • APPENDIX A. APPENDIX B. APPENDIX C. APPENDIX D. APPENDIX E. 30 ..... Audiogram Form . . . . . . . . . . . . . . . . . . . . Test Instructions • . . . . . . . . . . . . . . . . . . 33 Differences from Base Rate Scores for Heart Rate and Blood Pressure • • • • • • • • • • • • • • • • 34 Raw Scores • • • • • • • • • • • • 40 • • • • • • • • • • • • • • • • • • 46 Permissible Noise Exposure Limits Chart • • • • • • • • • • • LIST OF REFERENCES • • • • • .. v 31 32 LIST OF TABLES Table I II III Page 3 x 5 Analysis of Variance for Heart Rate for Stimuli ~f No Noise, White Noise and 250 Hz ...... 13 Mean Average for Heart .Rate for Stimuli of No Noise, . White Noise and 250 Hz • • • • • • • • • • • • • 14 3 x 5 Analysis of Variance for Systolic Blood Pressure for Stimuli of No Noise, White Noise and 250 Hz • • " • • • • • • • • • • • • • • • • • • • IV v VI VII T Test for Systolic Blood Pressure Between 15 Minute No Noise and 15 Minute 250 Hz • • • • ~ • • • 16 • • • • • 18 Mean Average for Systolic Blood Pressure for Stimuli of No Noise, White Noise and 250 Hz • • • • • • 20 3 x 5 Analysis of Variance for Diastolic Blood Pressure for Stimuli of No Noise, White Noise and 250 Hz • • • • • • • • • • • • • • • • • • • • • • 21 Mean Average for Diastolic Blood Pressure for Stimuli of No Noise, White Noise and 250 Hz • • . 24 . vi • • LIST OF ILLUSTRATIONS Figure I II III Page Composite of Mean Scores for Heart Rate for Stimuli of No Noise, White Noise and 250 Hz • • • • • • Composite of Mean Scores for Systolic Blood Pressure for Stimuli of No Noise, White Noise and 250Hz • • • • • • • • • • • • • • • • • • • • • • • Composite of Mean Scores for Diastolic Blt'Od Pressure for Stimuli of No Noise, White Noise and 250 Hz • • • • • • • • • • • • • • • • • • • • • • • vii 15 • 19 • • 23 • Introduction and Rationale Our bodies are in a delicate state of equilibrium. This state can be disturbed in many ways. : ordinarily there are built-in systems in the body which tend to preserve this internal and autonomic equilibrium. It now appears, however, that noise is a factor which can produce disturbances in various physiological activities of the human body (Kryter, 1970). Not until recently has noise as a form of pollution attracted attention. While noise was once thought of as a by-product unique to industry, it has now spread to our cities and into our environment (Welch, 1970). Some communities already have noise levels which exceed those found in industry (Sataloff, 1957). It has long been known (Kryter, 1970 and Peterson and Gross, 1972) that noise exposure causes hearing loss; however, more recent studies indicate that other non-auditory effects on one's body can also take place as a result of such exposure. High noise levels of 120-150 decibels (dB) at certain resonant frequencies of body structures can produce noticeable symptomatic reactions (Sataloff, 1957). Even moderate noise levels produce temporary changes in the size of some blood vessels, although it is not known how much these effects eventually produce permanent change (Bail~y, 1969). The production of stress and fatigue by noise exposure is difficult to verify in a meaningful way though these effects cannot be ignored. So great is this concern over the hazardous effects of noise on man that the Occupational Safety and Health Administration (OSHA) of the United States 2 Department of Labor recently set guidelines for the protection of workers in noisy areas. These standards apply to every working man and woman in the United States. These guidelines including the time limits individuals are allowed to be exposed to industrial noise may be seen in Appendix A. The Auditory Mechanism The ear is one of the most complex and intriguing organs known to science, and it is necessary to understand, at least in a general way, how this delicate and intricate mechanism functions in order to appreciate more clearly the various aspects of the problems of industrial deafness {Sataloff, 1957). Air conducted sound waves must travel through the outer, middle ~d inner ear in order for hearing to occur (Davis and Silverman, 1970). The outer ear consists of a fleshy appendage attached to the head and the ear canal, both of which serve to channel sound waves toward the elastic tympanic membrane commonly known as the eardrum. The conically shaped tY1D- panic membrane transforms the acoustic energy into mechanical energy. The ossicular chain, acting as an impedance transformer transmits the vibrations of the tympanic membrane to the oval window. This window moves in and out, much like a piston, generating pressure waves in the perilymph, a nearly incompressible fluid in the inner ear. The pressure differential that results moves the basilar membrane and the organ of Corti. The hair cells in the organ of Corti transform the mechanical motions into nerve impulses, which are transmitted through the eighth nerve into higher centers in the brain where they are decoded and interpreted as sound. As can be noted then, there is no distinction made by the ear between sound and noise (Kryter, 1970 and Rose, 1971). 3 The human ear is sensitive to sound waves vibrating at frequencies as low as 16 cycles per second or Hertz (Hz) and to those as high as 20,000 Hz, but man will not hear any of these frequencies unless they are loud enough. Sataloff (1957) points out that our ears are most sensitive in the frequency range between 1,000 and 3,000 Hz. In this middle frequency range it takes less sound energy for tones than it does for tones above or below these levels. As we grow older, higher frequency sensitivity decreases; so that many adults are not able to hear above 12,000 Hz, and it is not uncommon for persons to ·have difficulty hearing tones above 8,000 Hz. The Effects of Noise Welch and Welch (1970) postulated that noise may produce permanent damage and actually result in a partial loss of hearing if exposure is for long periods of time at high intensities. They further state that noise produces emotional reactions of annoyance, irritability, loss of attention and other conscious factors. It was recently reported (Bailey, 1969) that Medical research is beginning to show that loss of hearing is by no means the only ill effect of noise. Loud sounds cause blood vessels to constrict, the skin to pale, muscles to tense and adrenal hormones to be suddenly injected into the blood stream ••• Millions of city dwellers with heart disease, high blood pressure and emotional illnesses need protection from the additional stress of noise ••• Ears cannot shut out noise the way eyelids shut out light. The reflex effect which causes constriction of blood vessels occurs with equal intensity during sleep with many people showing fatigue from their effort to remain asleep in spite of noise (p. 78). Lehman (1956) and Tamm and Jansen (1962) found that exposure to 90 dB Sound Pressure Level (SPL) or white noise caused vasoconstriction of blood vessels which persisted for the duration of the noise. This condition persisted to the same degree in persons long accustomed to such noise as it did to those not regularly exposed to it. 4 Normal Hearing Individuals. Rosen et al., (1962) studied the hearing of an isolated primitive black tribe in southeast Sudan, the Maabans. These people live in an environment where noise rarely exceeds 40 db Sound Pressure Level. It was reported that they never have high blood pressure, and coronary heart disease is unknown. have better hearing with aging. They live longer and Rosen concluded that a single burst of white noise of 90 dB will not damage hearing; however, when an individual is exposed to such noise for many years, a cochlear hearing loss results. If an individual has a disorder such as atherosclerosis or coronary heart disease, this noise exposure could be harmful. Levi (1967) reported an increase in excretion of catecholamines (chemicals excreted by the endocrine glands - found in urine) as a result of workers being subjected to work in industrial noise. Arguelles et -al., - (1970) support Levi's findings and reported that exposure of normal, hypertensive and psychotic patients to a sound of 2,000 Hz for 30 minutes at an intensity of 90 dB caused endocrine disturbances (hormonal secretions). in many hypertensive patients. Blood pressure rose significantly Noise proved to be an important stressing agent capable of causing disturbances in cardiovascular and psychotic subjects. Kryter (1970) points out it is conceivable that intense low frequency sounds below 20 Hz effects on man. (infr~sonic) could have particularly adverse In addition to possible stimulation of the vestibular system and pain in the ear, sound in the region of 10-75 Hz could cause resonant vibrations in the chest, throat and nose cavities. Sataloff (1957) indicated a tickling sensation may be present in the ears, nose and throat and that we also may feel our skulls vibrate 5 in the presence of intense noise. A similar sensation in the chest may occasionally produce nausea and vomiting in some individuals. These findings agree with the data of Davis (1948), Brewer and Breiss (1960) MOhr (1965) and Peterson and Gross (1972). Deaf Individuals. The term deaf applies to those in whom the sense of hearing is non-functional for the ordinary purposes of life (Katz, 1972). In this study no distinction will be made between those Who are born deaf (congenitally deaf) and those who are born with normal hearing but in whom the sense of hearing became non-functional later through illness or accident {adventitiously deaf). Buyniski (1958) and Kryter (1970) reported that deaf employees in a large company made four to five times as many trips to the company dispensary per year and suffered greater medical pathologies than did normal hearing employees. These authors indicated that many of their complaints were coughs, hoarseness, otalgia and lesions often associated with working in noisy environments. Ades et al., (1958) exposed persons who were deaf to intense tones and noise. Such deaf individuals displayed similar pain levels to intense sound as did normals. Deaf subjects without eardrums, however, were able to withstand pain at higher levels than those having intact drums. It might be concluded then that pain thresholds might be determined by receptors in the tympanic membrane (eardrum). Statement of the Problem It is not an uncommon practice for large banks and Federal institutions to hire deaf individ~al~to work in computer rooms, print shops or other environments where noise often exceeds 120 dB. The theory here is that these people already deaf, could not have their hearing impaired by such noise exposure and thus the employer would not be liable for additional hearing loss encountered. The fact that such institutions are solving an employment problem for many of our aurally handicapped citizens, while at the same time helping to overcome their own noise problems, may not be as commendable as it would appear if, in fact, these employees are receiving some adverse systemic changes due to such exposure. There has been considerable research performed concerning the auditory effects of noise on man; however, very few studies relating to the nonauditory or physiological effects of noise have been reported in the literature. Since the deaf have their auditory faculties diminished, they have been almost entirely ignored in noise effects testing. It is believed by Buyniski (1958) Brewer and Breiss (1960) and Kryter (1970) that it would be helpful to learn more concerning the vibratory (physiological) aspects of noise on the deaf. deaf? How much noise is harmful? the deaf? Is noise harmful to the How does noise affect the bodies of What part does noise play in the future of the deaf? It is hoped that a thorough understanding of the effects of noise on the deaf may be obtained and eventually provide a more reliable answer to the now unanswered questions of the effects of noise on such individuals. 6 7 An attempt shall be made to answer the following questions: 1. Is blood pressure significantly affected in deaf individuals who are exposed to 110 dBA of white noise? 2. Is blood pressure significantly affected in deaf individuals who are exposed to a 250 Hz pure tone at 110 dBA? 3. Is heart rate significantly affected in deaf individuals who are exposed to 110 dBA of white noise? 4. Is heart rate significantly affected in deaf individuals who are exposed to a 250 Hz pure tone at 110 dBA? Methodology Test Site All testing was c~~4ucted in the Auditory Research Laboratory at Florida Technological University in Orlando, Florida. Subjects Two general requirements for all individuals included in this study were that they had no previous participation in noise experiments and that they were deaf. All ten deaf individuals were subjected to the three noise conditions--no noise, white noise and a 250 Hz pure tone. Instrumentation Rooms. A testing suite (Industrial Acoustic Company Series 1200) was used in all audiometric testing employed in this study. The noise level of the test room was within the standards set down by the American Standards Association for a room to be used for audiologic testing. Pure-tones. Pure tone audiometries were performed using a clinical and research audiometer (Grayson Stadler 1702). A matched set of earphones (Telephonics TDH 39) using MX 41 AR cushions were used for all pure-tone testing. A check of calibration of the audiometer was done each day prior to testing. Calibration. A Sound Pressure Level Meter B and K model 2803 was utilized to assure proper calibration of the audiometer, headsets and sound speakers. 8 9 Stimulus Presentation. Both the white noise and 250 Hz pure tone were presented via sound field utilizing the Grayson Stadler (1702) Audiometer. A calibrated noise booster (shure) was used to increase the intensity of the signal above normal audiometer limits. Blood Pressure and Heart Rate. Blood pressure and heart rate were measured using a physiograph polygraph model projector (Narco Bio-Systems, Inc., Type PMP-4B) equipped with a graphic recorder. Stimulus Materials Both of the noise stimuli were generated by the Grayson Stadler 1702 Clinical Audiometer. The stimuli were th.en amplified to 110 dBA through a Bozak Amplifier System and presented to the subjects in a sound field environment. Procedure A calibrated check of all equipment was completed prior to each testing session. All individuals were given written instructions informing them of the procedures they were to follow (see Appendix C). After they had read the instructions and the researcher was confident the individuals understood them, each was asked to be seated in the testing chamber. The pure tone air conduction hearing test that was administered to each subject followed the guidelines recommended by Bragg (1970), and all responses were recorded on the audiograms. Individuals that met subject inclusion requirements were placed in the sound suite and given a three minute rest period. During this were attached to the subject. t~e the electrodes of the physiograph Each subject was tested to determine base lines of heart rate and blood pressure prior to being subjected to the experimental conditions. Depending upon which group the subject belonged, he was presented with no noise or a noise stimulus of 110 dB through the speakers. Blood pressure and heart rate were measured and recorded automatically for the base rate after (1) one minute, (5) five minutes, 10 11 (10) t en minutes and (15) f ifteen minutes of stimuli. Upon completion of the t esting, each subject was removed from the test chamber and thanked fo r hi s coopera tion . RESULTS Heart Rate Table I represents - t~e results of a completely randomized two dimensional (3 x 5) Factorial Analysis of Variance for all conditions of heart rate. There were no F values found to be statistically significant (P< .05) relative to heart rate (Winer, 1962). Inspection of Table II reveals that heart rate in conditions of no noise appeared to be consistent over all time intervals. The mean average heart rate was 80 beats per minute {bpm) for the 15 minute period. Table II further suggests that heart rate in conditions of white noise lowered over the 15 minute period from 82 bpm to 81 bpm. Inspection of Figure I reveals that although there were no significant F ratios obtained for heart rate in the 250 Hz condition, a 4 bpm increase in heart rate did take place during this period. Systolic Blood Pressure The results of a completely randomized two dimensional (3 x 5) Factorial Analysis of Variance for all conditions of Systolic Blood Pressure {SBP) are presented in Table III. {p ~ Significant F ratios .05) were not obtained on the main effects; however, a significant F ratio was obtained within subjects, indicating that interaction between the noise stimulus and time presentation does exist. For this reason, a one-way analysis of variance was performed for all conditions and again revealed no significant F ratios. 12 13 TABLE I 3 x 5 Analysis of Variance for Heart Rate for Stimuli of No Noise, White Noise and 250 Hz Source of Variation ss DF MS F Between Subjects: 133.3733 A 19916.90 Er 2 27 66.68667 0.090 737.6630 Within Subjects: 13.57333 J 185.2267 AJ 1333.200 Er Legend: A J Er = Noise = Time = Respective 4 3.393333 8 23.15333 108 12.34444 Error Terms for Analysis 0.275 1.876 14 TABLE II Mean Average for Heart Rate for Stimuli of No Noise, waite Noise and 250 Hz (1) (5) (10) Base Rate One Minute Five Minutes Ten No Noise 81.80 81.80 White Noise 82.10 Noise Stimulus 250 Hz Pure Tone Noise Mean Minutes (15) Fifteen Minutes Time Mean 79.40 79.60 79.00 80.32 80.80 81.20 81.00 80.60 81.14 80.00 82.60 84.40 82.40 83.60 82.60 81.30 81.73 81.67 81.00 81.07 81.35 15 Figure I CompOsite of Mean Scores for Heart Rate TIME Base Rate Heart Rate (1) One Minute (5) Five Minutes (10) Ten Minutes (15) Fifteen Minutes 86 85 84 83 82 81 80 "'+----- - - - - +- - - - - - -- - - -+ 79 78 77 Legend: + = No Noise 0 = 250 * = White Hz Noise 16 TABLE III 3 x 5 Analysis of Variance for Systolic Blood Pressure for Stimuli of No Source of Variation Nois~, ss Whtte Noise and 250 Hz DF MS F 2 134.2467 0.264 27 509.3407 Between Subjects: A . 268.4933 Er 13752.20 Within Subjects: J 118.4267 4 29.60667 1.862 AJ 427.5733 8 53.44667 3.362 108 15.89630 1716.800 Er Legend: A J Er = Noise = Time = Respective Error Terms for Analysis . 17 Further t tests were performed to find the source of this interaction. One t ratio approached significance at the {p< .05) on the one tailed test, however, since no directional hypotheses were formed, the two tailed value would be more appropriate. may be seen in Table IV. justifiable ~or Results of the t test Although use of the one tailed test was not this study, the interacti~n affect is noted between the 15 minute no noise and the 15 minute 250 Hz condition. An increase in SBP for both white noise and 250 Hz is demonstrated over the control condition for the same period. No Noise. Inspection of Figure II indicates that.SBP for conditions of no noise remained at the base rate level of 115 millimeters mercury (mm) at one minute, and at the five minute measurement. SBP increased at the 10 minute measure to 117 mm and reduced to 112 mm at the fifteen minute reading. for the entire fifteen White Noise. As can be observed in Table V, the mean SBP minut~ time period was 115 mm. Table V further reveals that the SBP for the 250 Hz condition increased relative to the base rate at all time periods. The greatest increase, as can be seen in this table, was noted at the fifteen minute reading where the SBP score elevated 8 mm. The mean of all readings during the 250 Hz condition was 118 mm or an increase of 4 mm in the SBP over the base rate. Diastolic Blood Pressure Table VI represents the results of a completely randomized two dimensional (3 x 5) Factorial Analysis of Variance for all conditions of Diastolic Blood Pressure (DBP). There were no F values found to be 18 TABLE IV T Test for Systolic Blood Pressure Between 15 Min~te No Noise and 15 ~finute 250 Hz Number of Observations in Sample No Noise 250 Hz 10.000 10.000 Arithmetic Mean No Noise 250 Hz 112.5000 122.4000 Standard Deviation No Noise 250 Hz 11.0204 10.4709 Estimated Standard Deviation of Populations No Noise 250 Hz 11.6165 11.0373 Estimated Standard Error of Mean No Noise 250 Hz 3.6734 3.4903 Absolute Value of the Difference 9.9000 T Statistic 1. 9537 19 Figure II Composite of Mean Scores for Systolic Blood Pressure Systolic Blood Pressure Base Rate (1) One Minute TIME (5) Five Minutes (10) Ten Minutes (15) Fifteen Minutes 123 122 121 120 119 118 117 116 -_..+--- ----:.- 115 , "' "' ' '' \ '\ ' 114 113 112 111 110 Legend: -~' ~ ~ + = No Noise * ·=White Noise 0 = 250 Hz ' \ '\ + 20 TABLE V Mean Average for Systolic Blood Pressure for Stimuli of No Noise, White Noise and 250 Hz (1) (5) (10) (15) Base Rate One Minute Five Minutes Ten Minutes Fifteen Minutes Time Mean No Noise 115.00 115.50 115.30 117.20 112.50 115.10 White Noise . 117.20 116.70 116.10 116.90 118.20 117.02 114.30 116.10 119.90 118.10 122.40 118.16 115.50 116.10 117.10 117.40 117.70 116.82 Noise Stimulus 250 Hz Pure Tone Noise Mean 21 TABLE VI 3 x 5 Analysis of Variance for Diastolic Blood Pressure for Stimuli of No Noise, White Noise and 250 Hz Source of Variation ss DF MS F 15.70667 0.038 Between Subjects: 31.41333 A 11261.76 Er 2 27 417.1022 Within Subjects: 64.37333 J 4 16.09333 1.919 16.62333 1.982 AJ 132.9867 8 Er 905.8400 108 Legend: A = Noise J = Er T~me = Respective Error Terms for Analysis 8.387407 22 statistically significant (p< .OS) relating to DBP. There was an F ratio that approached significance (p<: .OS) within subjects. This would suggest interaction between the noise stimuli and the time presentations. This interaction is further illustrated in Figure III. Because of this suggested interaction a one-way analysis of variance was performed for all conditions.. There were no F values found to be statistically -significant . (p <.OS) for the DBP. No Noise. As can be observed in Table VII, the mean DBP for the entire fifteen minute period was 71 mm which represents an increase of only 1 mm .over the base rate. White Noise. Table VII further illustrates that the mean DBP for the lS minute period was 71 mm, the same as the base rate score for this condition. Interaction exists between the white noise and the no noise stimuli at the five minute reading only. 2SO Hz. Although there were no significant F ratios obtained for DBP for the 3 x S analysis or the one-way analysis, these scores did increase as a function of time from a base line score of 70 mm to a score of 74 mm at the 15 minute interval. The mean DBP for all time intervals was 72 mm or an increase of 2 mm over the base rate. Interaction existed between 2SO Hz and white noise at the five minute reading. A t test was performed which again revealed no significant t ratios for conditions of DBP. 23 Figure III Composite of Mean Scores for Diastolic Blood Pressure Diastolic Blood Pressure TIME , Base Rate 77 76 75 74 73 72 71 70 69 68 67 Legend: + = No Noise * = White Noise 0 = 250 Hz (1) One (5) Five (10) Ten Minute Minutes Minutes (15) Fifteen Minutes 24 TABLE VII Mean Average for Diastolic Blood Pressure for Stimuli of No Noise, White Noise and 250 Hz Five Minutes (10) Ten Minutes (15) Fifteen Minutes Time Mean 70.40 71.70 71.70 70.30 70.76 70.70 73.50 70.80 70.60 71.40 71.40 70.10 70.60 72.30 74.00 74.40 72.28 70.17 71.50 ·71.60 72.10 72.03 71.48 (1) (5) Base Rate One Minute No Noise 69.70 White Noise Noise Stimulus 250 Hz Pure Tone Noise Mean DISCUSSION Heart Rate Although heart rate increased when subjects were exposed to 110 dBA of 250 Hz tone over the 15 minute period and decreased in the presence of White noise at the same intensity (qv. Figure I), these differences were not found to be statistically significant. As may be observed in Table II, heart rate generally decreased in the control condition as a function of time. This decrease may be the result of the subject simply relaxing since no adverse stimuli was being presented and all subjects were assumed to be aware of the procedures being followed. Examination of heart rate differences from base rate in the 250 Hz condition at the 15 minute time interval revealed seven of the ten subjects to have elevated heart rates (see Appendix D). Further inspection of Appendix D revealed, as expected, that heart rate in the no noise condition remained the same or decreased from the base rate over the 15 minute session. An unexpected observation, however, was revealed in the white noise condition (qv. Table II) where heart rate also generally reduced as a function of time, similar to the pattern found in the no noise condition. One might reason that white noise may have an anesthetic effect on some individuals (reported by Stevens, 1966) which may bring about a reduction of cardiac . rhythm. Since all of these subjects were deaf, it is 25 26 possible that the vibratory rather than the acoustic _transmission may be an important consideration in determining the use of such anesthetic techniques •. Systolic Blood Pressure Measurement of the ~BP and DBP were analyzed separately. Although there were no significant F values obtained between subjects, a significant F ratio was obtained within subjects. The significance here may be explained as interaction between the noise ·conditions and the time intervals. The combination of the noise conditions and the time intervals and their relationship to each other as factors of the design, may have created an internal imbalance within the analysis of variance, thus creating the significant F ratio within subjects and negating ~he F ratio between subjects. Further examination was performed within subjects using t tests. The only result that approached significance may be observed in Table VII. It would seem justifiable to conclude that specific noises do indeed produce systemic body changes at 110 dBA. The specific acoustic signal of 250 Hz produced an increase from 114 mm to 122 mm over the 15 minute period (qv. Table V). The significance here is probably due to the large SBP difference (8 mm) from base readings occuring at the 15 minute measurement. Diastolic Blood Pressure Although there was an increase in the DBP, from the base rate over the 15 minute period f9r the 250 Hz stimulus, no significant F ratios were found between subjects, however, this analysis d'id 27 approach significance within subjects. This may be suggestive of interaction between noise conditions and time intervals. If these results were significant, the combination of the noise conditions and the time intervals and their relationship to each other as factors of the design, may have created an internal imbalance within the analysis of variance, thus creating the significant F ratio within subjects and negating the F ratio between subjects. It would seem· that neither noise nor time contingencies alone produced statistically significant differences in the DBP, however, an increasi~g DBP for the 250 Hz condition may be noted by examination of the raw data as illustrated in Appendix E. Whereas during white noise there appeared to be a decreasing trend in DBP from the base rate, it might have been hypothesized by a priori reasoning that given a longer period, white noise would tend to reduce DBP. Likewise, the 250 Hz condition, if continued for a longer period · ·w ould terid · to give an elevated DBP reading: It would appear that white noise has its greatest affects at the one minute level which might be explained as a function of subject adaptation; that is, the initial traumatic effect of the noise is adjusted to by the subject and, therefore, systemic changes over a longer time are not of the same magnitude as noted at the onset of the noise. Such adaptation to noise exposure, according to the research on normal hearing individuals reported earlier, has not been found. It would appear that the SBP and the DBP act somewhat independently under noise conditions of 250 Hz. 28 As was noted earlier, the 250 Hz signal produced an increase in SBP of 8 mm over the 15 minute period, whereas DBP for the same period increased only 4 ~· White noise readings, however, for both SBP and DBP, produced increases of 1 mm for the 15 minute time period. Pathology As indicated earlier, the Occupational Safety and Health Administration (OSHA) established guidelines for ear protection in workers exposed to excessive noise. It would seem, however, that deaf workers are ignored with this legislation since they have already supposedly lost all audition. In addition to hearing loss, this study indicates that physiological changes in heart rate and blood pressure do result from noise exposure. Deaf individuals, as well as normals, who may suffer from arteriosclerosis, hypertension and cardiac problems in general should not be exposed to such environmental health hazzards. Other complications such as glacoma, diabetes, hearing impairment, vascular and nervous disorders, to name a few, are also aggravated by blood pressure and heart rate increase and thus the deaf individual should not be inflicted with this form ~ of pollution. These noise conditions would seem to tend to shorten life span and decrease somatic efficiency. Implications for Further Research A measure of skin resistance alterations might be of interest in studying physiological changes occuring as a result of noise exposure. Through use of a psychogalvanometer and/or a Palmer sweat instrument, a researcher might be able to gain insight on additional vibratory 29 reactions to intense noise stimulation. Such autonomic reflexes measured in this fashion may have implications toward understanding the anesthetic effect of white noise as suggested by this research. The trends noted by examination of the raw data suggest that if either variables of .time or intensity of the noise were increased both heart rate and blood pressure would also elevate. Since many individuals are exposed to noise for many hours during a work day, a measure of these effects over a longer duration may be of importance with respect to the overall health of the individual. Deaf workers employed in noisy environments are rarely exposed to discrete frequencies such as 250 Hz or, on the other hand, to noise with as wide a spectrum as white noise. Other noise including the steady state and impact type typical of industry, though not as efficient for experimental control, would be of interest in assessing physiological effects upon deaf workers and would deserve consideration for further investigation. SUMMARY A review of the literature reveals that experimentation with the . · deaf has been limited in the area of noise exposure. This is partially because the deaf already have their auditory mechanism destroyed and, therefore, it is assumed that no further damage could occur to the auditory mechanism. It was decided to investigate the physiological effects of noise, if any, upon the deaf. All subjects were seated in a sound treated chamber and exposed to 110 dBA of white noise and 250 Hz pure tone in a sound field environment. dition. A no noise period was also employed as a control con- Heart rate and blood pressure were measured just prior to each noise exposure (base rate) and then again at 1, 5, 10, and 15 minutes after the onset of the noise. All subjects were exposed to all conditions using a counter balanced design and measurements were performed during one setting with appropriate rest periods between conditions. These heart rate and blood pressure findings were subjected to analysis of variance. Results of this treabment yielded a significant F ratio for SBP within subjects and approached significance within subjects for DBP. It would appear that from results of this study that the Federal Government and industry should be made aware of the possible harmful effects of noise exposure to the deaf. 30 APPENDIX A 31 APPENDIX A Occupational Safety and Health Administration Guidelines for Noise Exposure of Workers Protection against the effects of noise exposure shall be provided when the sound level exceeds those shown on Table I of this section when measured on the A scale of a standard sound level meter at slow response ••• TABLE I Permissible Noise Exposures Sound Level dBA slow Duration per day, hours 8 90 6 92 4 95 3 97 2 100 1~ 102 1 105 ~ 110 %or 115 less The abbreviation of dB in the right-hand column of the table stands for decibels, the unit of measurement of sound levels. The A scale is one of several on the sound level meter, a measuring instrument used to determine sound intensity. On this scale, the instrument reacts in much the same way as does the human ear. APPENDIX B APPENDIX B 32 FLORIDA TECHNOLOGICAL BOX 25000 UNIVERSITY ORLANDO, FLORIDA tARTMENT OF COMMUNICATION )2816 Report of Audiologic Evaluation Date ·In· 125 - - - Sex_____ Age Audiogram Audi ogram Key FREQUENCY IN CYCLES PER SECOND AIR CONDUCTION 250 500 2000 1000 ~000 1500 750 0 Right e ar (red) X left ear (blue) 8000 3000 6000 -10 • I Free fie ld aided (black) ! With maskl ng: I i 0 i 0 0 10 BONE CONDUCTION ~ 20 0 • Right e ar (red) left ear (blue) ( ( Right ear (red} ] left ear (blue) 0 z c 30 "' ~ : •.. = = = ~0 ~ z 50 ( NR NO RESPON SE DNT DID NOT TEST CNT COULD NO T TEST NBN = NARROW BAND NOISE FA = FLETCHER AVERAGE HL = HEARING LE VEL SPL = SOUND PRE SSURE LEVEL . I Ill • I I 60 I I I I 70 I lI I 80 I Examiner I I I I 90 I AUDIOMETER USED :; 100 . TYPE OF MASKING I I I I I 110 AIC ~ t/C I RELIABILITY _,__r--Rf-R- ---L- - R - - L - 1--R-- - L - - R - -l+R- - L - - R - -L B/C ~MMENTS: BEKESY RESULTS Right: Left: AVERAGE LEVEL. FOR TEST TONES SPEECH AW<1.R~ff•lS'; THRESHOLDS LIVE: • VOl~[ Rt BONE: Rt - dB dB lt FIELD: FIELD: (Al l l dB ........ ftEBER: 'r q .._____ ~ PB-50 OTHf.P. Y/22 dB Ill Ill PKB OTHER LV REC % lt % It _ _ _____. Field - % ., -· (All lEVElS RE CliENT'S SRT) FVE!.S P.f NOP.MAl SRT) --· BING: Right: l~h . far Pos. Pos. Nrg. Neg. Pos Pos. l'!t"g ------- Neg. ---- Freq. V at _ _ _ _._ SISI TES T RESULTS RINNE: Right: Left: V IV IV Rt ~8 lf II II TONE DECAV TEST AUDIOMETRIC: lat. to -------- ~---------- ~e Rt dC db lt SPONDff:, I I SPEECH DISCR IMINATION - P.ECEr riON (500, 1000 & 2000 cps} AIR: EFFECTIVE MASKING RE OdB HL A/C Decay Freq • Ear: Right: left - ell ? ? APPENDIX C 33 APPENDIX C Instructions Hello, MY name is Mr. Bartee, and I am a will be participating in an experiment · entire process will take approximately me assure you that you will experience graduate student at F.T.U. You on environmental sounds. The forty-five (45) minutes. Let no pain or discomfort. First, I would like to ask you some questions: 1) 2) 3) 4) Name, age, date Address aP.d phone number Have you previously participated in any experiments? If yes, were you ever involved in a study about noise? Pure Tone Audiometries Now I would like to conduct a simple screening hearing test. take a seat inside the booth and relax. Please You are going to be listening to some tones which will sound like · short whistles. Every time you hear a sound, press the button and release it.. Do ~ot hold the button down, just press and release. Press the button only· when you hear the whistle--do not guess. Do you understand? For the next part of the experiment, I am going to attach some wires to your wrist and leg and a blood pressure cuff on your arm. These will help measure some of your body functions. Next I would like you to sit back ann relax for about fifteen (15) minutes as you will be listening to some form of environmental sounds. Do you understand? After the experiment is completed, please do not discuss this experiment with your friends as we may be needing them to help us also. Do you have any questions? We will begin in a few minutes. APPENDIX D 34 APPENDIX D Heart Rate Difference from Base Line for No Noise (1) (5) (10) (15) Ten Minutes Fifteen Minutes Subject No. Base Rate One Minute Five Minutes 1 84 -4 -2 - 4 -4 2 70 -4 -4 0 0 3 76 0 -4 0 -4 4 80 0 -2 - 2 -2 5 100 +6 +8 +4 -4 6 70 0 -6 - 6 -8 7 86 . -2 -8 -10 -6 8 80 -2 -2 0 0 9 72 0 0 0 0 10 100 +6 -4 - 4 0 35 APPENDIX D Heart Rate Difference from Base Line in White Noise. Subject No. Base Rate (1) (5) One Minute (15) Five Minutes (10) Ten Minutes Fifteen I.fi.nutes 0 -2 +2 + 2 1 80 . 2 70 -4 +6 0 - 4 3 80 -4 -2 -2 +4 4 80 +4 -2 -2 + 6 5 108 0 +2 -8 -14 6 70 -6 -6 0 - 6 7 82 0 -2 +2 . +2 8 76 -2 44 +4 - 2 9 72 -2 -8 -4 - 2 10 103 +1 +1 -3 - 3 36 APPENDIX D Heart ·Rate ·Difference from Base Line 250Hz Pure Tone Subjec·t (1) (5) Five Minutes (10) Ten 1-iinutes (15) Fifteen Minutes No. Base Rate One Minute 1 80 +4 +8 +2 + 2 2 76 +4 +12 +12 +14 3 74 + 2 - 2 - 2 - 2 4 80 +6 0 - 2 - 2 5 92 - 4 +18 - 2 +6 6. 66 0 + 2 2 - 2 7 82 +10 + 2 +2 +4 8 78 +4 0 + 6 + 6 9 72 - 2 2· +4 +4 10 100 +4 + 6 + 6 + 6 37 APPENDIX D Blood Pressure Difference from Base Line in No Noise (1) (5) Subject No. Base Rate One Minute . Five Minutes (10) Ten Minutes Fifteen Minutes 1 104 70 - 3 0 - 3 0 +4 0 - 2 0 2 108 70 + 6 +4 - 1 + 2 +5 +5 . - 2 +4 3 119 60 0 0 + 1 0 + 2 0 ::_]_ 0 4 106 75 - 1 +4 +4 + 3 +2 +4 0 +4 5 128 64 - 2 0 - 4 + 2 - 2 - 2 + 6 - 2 6 124 86 +12 - 1 +14 +8 +18 +2 + 8 +4 7 121 80 - 5 - 5 0 0 - 5 0 - 7 0 8 -116 . 62 - 2 + 2 + 2 + 6 - 1 +4 -10 +4 9 104 58 0 - 2 + 6 +3 + 6 - 3 +3 120 72 0 - 2 - 5 - 4 + 1 - 1 10 0 - 4 (15) - 8 38 APPENDIX D Blood Pressure Difference from Base Line in White Noise (1) (5) (10) (15) One Ten Minutes Fifteen 1-tl.nutes Base Rate Minute Five Minutes 1 . 104 70 -3 0 -3 0 -f-4 0 - 2 0 2 115 72 -6 +7 -6 -2 0 +2 +13 - 6 3 118 70 +5 -6 0 -9 -+2 -9 + 6 -10 4 110 78 -4 +2 -4 +1 -1 +3 +5 + 5 5 131 62 +1 0 +5 0 +1 0 +5 - 2 6 132 86 +5 +6 -f-4 +6 +9 +3 + 2 0 7 113 80 -2 0 -7 0 -9 -2 - 1 0 8 116 66 -2 +2 -7 -3 -6 -5 - 9 + 2 9 115 62 -2 +8 -+2 0 -1 +2 - 3 +8 10 118 71 +1 -1 -f-4 -2 -7 - 6 0 Subject No. -1 39 APPENDIX D . . Blood Pressure Difference from Base Line in 250 Hz Pure Tone (1) One Minute (5) Five Minutes (10) Ten Minutes 101 70 +9 + 3 +10 + 1 0 + -6 2 110 73 -3 -2 0 +4 + 6 + 3 +12 + 7 3 124 60 0 -1 - 4 + 3 - 1 +4 + 2 0 4 110 75 +2 +5 +11 + 5 +11 +10 +18 +6 5 126 61 0 +1 + 8 - 3 +2 - 3 +3 + 1 6 130 89 +7 0 + 1 +2 - 4 +14 + 6 108 72 -3 +6 + 2 0 +2 + 8 + 2 + 8 8 115 66 +8 +6 +15 + 5 + 3 +10 + 3 0 9 99 59 +3 -1 +15 + 1 +11 + 5 +12 + 3 10 120 76 -2 +2 + 6 - 2 +4 - Subject No. Base Rate 1 7 -5 + 2 (15) Fifteen Minutes 7 0 + 8 +2 APPENDIX E 40 APPENDIX E Raw Scores (Heart Rate) for Conditions of No Noise (1) (5) Subject No. Base Rate One Minute Five Minutes 1 84 80 82 .2 70 66 66 3 76 76 4 80 5 (10) Ten Minutes (15) Fifteen Minutes Mean 80 81 70 70 68 72 76 72 74 80 78 78 78 78 100 106 108 104 96 102 6 70 70 64 64 62 66 7 86 84 78 76 80 80 8 80 78 78 80 80 79 9 72 72 72 72 72 72 10 100 106 96 96 100 99 80 . 41 APPENDIX E Raw Scores (Heart. Rate) for Conditions of White Noise Base Rate (1) One Minute 1 80 80 78 82 82 80 2 70 66 76 70 66 69 3 80 76 78 78 84 79 4 80 84 78 78 86 81 5 108 108 110 100 96 104 6 70 64 64 70 64 66 7 82 82 80 84 84 82 8 76 74 80 80 74 76 9 72 70 64 68 70 68 10 103 104 104 100 100 102 Subject No. - (5) Five Minutes (10) Ten Minutes (15) Fifteen Minutes Mean 42 APPENDIX E · Raw Scores (Heart Rate) for Conditions of 250 Hz Pure Tone (1) (5) Base Rate One Minute Five Minutes {10) Ten }:.inutes (15) Fifteen Minutes Mean 1 80 84 88 82 82 83 2 76 80 88 88 90 84 3 74 76 72 72 72 73 4 80 86 80 78 78 80 5 92 88 110 90 98 95 6 66 66 68 64 64 65 7 82 92 84 84 86 85 8 78 80 78 84 84 80 9 72 70 70 . 76 76 72 10 100 104 106 106 106 104 Subject No. 43 APPENDIX E Raw Scores (Blood . ~ressure) fo~ (1) One Minute .. Conditions of No Noise {5) Five Minutes (10) Ten Minutes (15) Fifteen Minutes Mean Subject No. Base Rate 1 104 70 101 70 101 70 108 70 102 70 103 70 2 108 70 114 74 107 72 113 75 106 74 109 73 ·3 119. 60 119 60 120 60 121 60 112 60 118 60 4 106 75 105 79 110 78 108 79 106 79 107 78 5 128 64 126 64 124 66 126 62 134 62 127 63 6 127 86 136 85 138 94 142 88 132 90 134 88 7 121 80 116 80 118 80 116 80 114 80 117 80 8 116 62 114 64 118 68 115 66 106 66 113 65 9 104 58 104 58 102 61 107 64 101 61 103 60 10 120 72 120 70 115 68 116 73 112 • 71 116 70 44 APPENDIX E Raw· Scores (Blood Pressure) for Conditions of White Noise Subject No. Base Rate One Minute Five Minutes (10) Ten Minutes 1 104 70 101 70 101 70 108 70 102 70 103 70 2 115 72 108 79 108 70 115 70 128 66 114 71 3 118 70 -121 64 118 61 120 61 124 60 120 63 4 110 78 106 80 108 79 109 81 115 83 109 80 5 131 62 137 62 136 62 132 62 136 60 134 61 6 132 86 137 92 136 92 141 89 134 86 136 89 7 113 80 111 80 106 80 109 78 112 80 110 8 116 66 114 68 109 63 110 61 107 68 111 65 9 115 62 113 70 117 62 114 114 64 112 70 10 118 71 119 70 122 69 111 70 112 71 116 72 (1) (5) (15) Fifteen Minutes Mean 79 65 LIST OF REFERENCES LIST OF REFERENCES Ades, H. W., Davis, H., El~redge, D. H., Von Gierke, H. E., Halstead, W. C., Hardy, J. D., Miles, W. R., Neff, W. D., Rudnick, I., Ward, Jr., A. A. and Warren, D. R. Benox Report - An Exploratory Study of the Biological Effects of Noise. Chicago: University of Chicago Press, 1953. . Arguelles, A. E. et al., Endocrine and Metabolic Effects of Noise on Normal, Hypertensive and Psychotic Subjects. Physiological Effects of Noise. New York: Plenum Press, 1970. Bailey, A. Noise Is a Slow Agent of Death. New York Times, 1969. Bragg, V. C. Accomplishing the Pure Tone Audiogram. Audiological Library Series, 1970, VII, 15. Maico Brewer, D. W. and Breiss, F. B. Industrial Noise: Laryngeal Considerations. New York State Journal of Medicine, 1960, 60, 1737-1740. Buyniski, E. F. Noise and Employee Health. No. 6, 45-46. Noise Control, 1958, 4, Davis, H. and Silverman, R. Hearing and Deafness. Rinehart and Winston, Inc., 1970. New York: Holt, Griffith, J. (Ed.). Persons with Hearing Loss. Charles Thomas Publisher, 1969. Springfield, Illinois: Katz, J. (Ed.). Handbook of Clinical Audiology. Williams and Wilkins, 1972. Baltimore, Maryland: Kryter, K. D. 1970. The Effects of Noise on Man. New York: Academic Press, Lehmann, G. and Tamm, J. (1956). Uber Veranderungen der Kreisla uf dynamik des ruhenden Menschen unter Einwirkung von Gerauschen. Physiological Effects of Noise. New York: Plenum Press, 1970. Levi, L. Sympatho-Adrenomedullary Responses to Emotional Stimuli: Methodologic, Physiologic and Pathologic Considerations. In An Introduction to Clinic Neuroendocrinology (E. Bajusz, Ed.). S. Karager, Basel, 1967. Mohr, G. c., Cole, J. N., Guild, E., and Von Gierke, H. E. Effects of Low Frequency and Infrasonic Noise on Man. Aerospace Medicine, 1965, 36, 817-824. 46 47 Peterson, A. and Gross, Jr., E. E. Handbook of Noise Measurement. (7th ed.) Concord, Massachusetts: General Radio Co., 1972. Rainer, J. D. (Ed.). Family Mental Health Problems in a Deaf Population. (2d ed.) Charles Thomas Publisher, 1969. Rose, D. E. Audiological Assessment. Prentice Hall, Inc., 1971. Englewood Cliffs, New Jersey: Rosen, s., Bergman, M., · Plestor, D., El-MOfty, A., and Satti, M. Presbycussis. Study of a Relatively Noise Free Population in the Sudan. Annals of Otology, Rhinology, Laryngology, 1962, 71, 727-743. Sataloff, J. Industrial Deafness. New York: McGraw Hill, 1957. Stevens, S. S. (Ed.). Handbook of Experimental Psychology. John Wiley and Son, Inc., 1966. u.s. New York: Department of Labor. Guidelines to the Department of Labor's Occupational Noise Standards. Washington: Occupational Safety and Health Administration (Federal Register Section 1910.95, October 18, 1972). Welch, B. L. and Welch, A. S. Physiological Effects of Noise. New York: Plenum Press, 1970. Winer, B. J., Statistical Principles in Experimental Design, Series in Psychology, New York: McGraw Hill Co., 1962.