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Assessed the impact of noise on attentional strategies, learned helplessness, performance on cognitive tasks, and blood pressure. Third and 4th graders were tested on the same measures twice, with a 1-yr interval between sessions. Longitudinal data were used to determine whether Ss adapted to aircraft noise over the 1-yr period and to assess the effectiveness of noise abatement interventions introduced in a number of noise-impacted classrooms. Additional cross-sectional data are presented to provide further information on the utility of noise abatement. In general, there was little evidence for adaptation to noise over the 1-yr period. Noise abatement had small ameliorative effects on cognitive performance, Ss' ability to hear their teachers, and school achievement. (20 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Carnegie Mellon University
Research Showcase @ CMU
Department of Psychology Dietrich College of Humanities and Social Sciences
Aircra noise and children: Longitudinal and cross-
sectional evidence on adaptation to noise and the
eectiveness of noise abatement
Sheldon Cohen
University of Oregon,
David Krantz
Uniformed Services University of the Health Sciences
Gary W. Evans
University of California - Irvine
Daniel Stokols
University of California - Irvine
Sheryl Kelly
University of California - Irvine
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Recommended Citation
Cohen, Sheldon; Krantz, David; Evans, Gary W.; Stokols, Daniel; and Kelly, Sheryl, "Aircra noise and children: Longitudinal and
cross-sectional evidence on adaptation to noise and the eectiveness of noise abatement" (1981). Department of Psychology. Paper 768.
... The source of chronic noise exposure was external noise such as aircraft Negative effect for children aged 11 and 12 years old, no effect for children aged 13 years old b Children in the schools with high aircraft noise had significantly poorer scores than children in noise-abated schools but scores were not significantly different to those from children at schools with low aircraft noise c Children performed significantly poorer in the babble condition than the quiet condition but performance in the babble and environmental condition was not statistically significantly different to that in the quiet condition or babble condition d No effect for children with low intelligence, positive effect for children with high intelligence e Negative effect for children in second grade, no effect for children in sixth grade f The effect of reverberation was only apparent in the classroom noise condition (not quiet) and depended on the grade of the children with younger children performing poorer than older children in the longer reverberation condition but not the shorter condition. No significant effects of reverberation and listening condition on reaction time were found g egative effect for children in second grade, no effect for children in sixth grade h Negative effect for external noise, no effect for internal noise i Negative effect for hyperactive children, positive effect for control children Fig. 2 Publication years for the 15 papers reviewed in the numeracy performance scoping review noise [26,27] or traffic noise [28], internal building and service noise such as noise from heating and cooling systems [29,30], or internal occupied noise such as talking and movement noise from the children in the classroom [31,32]. The details of the acoustic conditions can be found in Table 1. ...
... Six studies used the results of standardised school tests to assess the impact of chronic noise exposure on children's mathematical performance. Cohen et al. [26] used the California Test of Basic Skills tests scores gathered from the schools. Haines et al. [27] used the children's United Kingdom National Standardised Assessment Test mathematics scores. ...
... Papers could have more than one result depending on the grade, but also on the types of noise or schools studied. For example, the study by Cohen et al. [26] was scored twice as there was a negative effect on mathematics performance for high noise schools compared to schools with high noise but noise abatement, but no effect for high versus low noise schools. As shown in Fig. 3, there was a mix of negative effects and no effects of noise on children's mathematical performance. ...
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Obtaining adequate numeracy skills and listening comprehension skills at primary school are vital for children’s future success. However, classrooms are often noisy and reverberant which may interfere with learning these skills. Two scoping reviews were conducted to synthesise research assessing the effect of different classroom acoustic conditions on (1) children’s numeracy performance and (2) children’s listening comprehension and to identify areas for future research. The PRISMA-ScR protocol was used for these scoping reviews. A comprehensive search of four online databases was conducted in September 2021 using the search term classroom AND ( noise OR reverberation OR acoustics ) AND ( numeracy OR math* OR arithmetic ) for the first scoping review, and in May 2022 using the search term classroom AND ( acoustic* OR noise OR reverb* ) AND (" listening comprehension" OR "auditory comprehension" OR "spoken language comprehension" OR "speech comprehension ”) for the second scoping review. The effect of the acoustic conditions on children’s numeracy was varied with most studies showing a negative or no effect of noise, but two showed a positive effect. Therefore, future research is needed to better understand the effect of different classroom acoustic conditions on children’s numeracy performance. For listening comprehension overall, signal-to-noise ratios below + 10 dB mostly had a negative effect on children’s listening comprehension compared to quiet conditions; however, variables such as the noise type, signal-to-noise ratio tested, the listening comprehension domain examined, the population studied, and the voice used for the stimuli affected this. Future research avenues to better understand these effects are proposed.
... Control schools were matched for socioeconomic status. In contrast, Cohen et al. 27 found that children from noisier schools due to aircraft noise exposure were less distracted by noise on a visual selective attention task than children from quieter schools. However, this advantage appeared to disappear after 4 years of exposure. ...
... In regard to the chronic exposure studies, four studies showed a positive effect of noise exposure. Cohen et al. 27 found that children from noisier schools due to aircraft noise exposure were less distracted by noise on a visual selective attention task than children from quieter schools. The study however found that while there was initial increased ability for noise-exposed children to tune out to auditory distractions, this advantage appeared to disappear after 4 years of exposure. ...
... Both groups of children were assessed in different types of noise (white noise, low-pass filtered noise, lunchroom noise, Moog sound synthesizer, man talking in a spooky voice, digit repetition, and reading of a passage). Cohen et al. 27 assessed children's cognition in natural ambient noise and while a story was played over headphones and found that children from noisier schools due to aircraft noise exposure were less distracted by noise but this advantage disappeared after 4 years of exposure. Given these results, it would therefore be beneficial for more studies to assess whether chronic noise exposure (both external and internal) improves children's attention and memory in noise. ...
Classroom acoustic conditions are often suboptimal, so how do they affect children’s cognition? This review synthesized research assessing the effect of different classroom acoustic conditions on children’s attention and memory. A comprehensive search of four online databases was conducted in January 2022 using the search term classroom AND (noise* OR reverberat* OR acoustic*) AND (cognit* OR attention OR memory OR processing). The results revealed 21 relevant papers plus an additional 10 from their references. The papers assessed the effect of a range of chronic and acute acoustic exposures on different attention and memory processes. Overall, the majority of studies showed a negative effect or no effect of higher noise levels, longer reverberation times, or lower speech clarity on children’s cognition. It would therefore be beneficial to improve classroom acoustic conditions if possible. Suggestions for future research to more fully understand the effect of different classroom acoustic conditions on children’s cognition are posed.
... We identified one study investigating noise exposure and performance on standardised academic tests, which found that children at low noise exposed schools had better task completion and test scores on reading and maths tests compared to children at high-noise exposed schools; covariates were not controlled for although authors state this was a homogenous sample (Papanikolaou et al., 2015). Prior to June 2015, Clark and Paunovic identified 11 papers on this subject (Cohen et al., 1973, Cohen et al., 1981a, Cohen et al., 1981b, Eagan et al., 2004, Green et al., 1982, Haines et al., 2002, Lukas et al., 1981, Pujol et al., 2014, Sharp et al., 2014, Shield and Dockrell, 2008, Zusman, 2007. This evidence supported an association but was low quality for traffic noise and very low quality for aircraft noise. ...
... Clark and Paunovic identified 12 studies of noise and attention in children (Cohen et al., 1973, Cohen et al., 1981a, Cohen et al., 1981b, Haines et al., 2001a, Haines et al., 2001c, Hygge et al., 2002, Lercher et al., 2003, Matsui et al., 2004, Sanz et al., 1993, Stansfeld et al., 2005, which were supportive of associations with attention for aircraft and traffic noise exposure, with one study finding evidence against an effect of railway noise on attention. ...
... Aircraft noise N = 7 Eagan et al., 2004/ Zusman, 2007Green et al., 1982;Sharp et al., 2014;Cohen et al., 1981a;Cohen et al., 1981b;Haines et al., 2002 Most literature supports Cohen et al., 1981a;Cohen et al., 1981b;Haines et al., 2001a;Haines et al., 2001b;Hygge et al., 2002;Matsui et al., 2004;Stansfeld et al., 2010;Stansfeld et al., 2005 Cohen et al., 1973, Sanz et al., 1993, Stansfeld et al., 2005, Julvez et al., 2021 Equal mix of supportive and unsupportive literature Cohen et al., 1981aCohen et al., , 1981bClark et al., 2012;Clark et al., 2013;Clark et al., 2006;Green et al., 1982;Haines et al., 2001a;Haines et al., 2001b;Haines et al., 2001c;Hygge et al., 2002;Klatte et al., 2014;Klatte et al., 2017;Matsui et al., 2004;Seabi et al., 2012;Seabi et al., 2015;Stansfeld et al., 2010;Stansfeld et al., 2005; Fuks et al., 2019, Tzivian et al., 2016a, Tzivian et al., 2016b, Tzivian et al., 2017, Ju et al., 2021, Weuve et al., 2021, Yu et al., 2020 *includes meta-analytic effect in Fig. 4 5 summarises the direction and strength of the evidence for different outcomes. 2 areas have not been studied ('n/a'), and Table 3 explicates the quality of overall evidence judgements made for each outcome and exposure, including the references of studies each encompasses. ...
Background: This systematic review provides a comprehensive synthesis of recent epidemiological evidence that environmental noise negatively impacts human cognition. Methods: We update a prior review with recent publications (PROSPERO CRD42019151923). The strength of evidence for associations was assessed using the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) framework. We also conducted random-effects meta-analyses where suitable. Results: 16 studies were identified and reviewed in tandem with 32 studies previously reviewed by Clark & Paunovic (2018). A meta-analysis from 3 studies found that reading comprehension scores in quiet classrooms were 0.80 (95% confidence interval: 0.40; 1.20) points higher than children in noisier classrooms. Meta-analysis of the impact of 1 dB (dB) increase in environmental noise on reading and language abilities gave a pooled beta coefficient of -0.11(95% confidence interval: -0.32; 0.10). A meta-analysis of Odds Ratios (OR) from 3 studies found higher odds of cognitive impairment in people aged 45 + with higher residential noise exposure (OR 1.40, 95% CI: 1.18;1.61). After qualitative synthesis of remaining studies, there was high quality evidence for an association between environmental noise and cognitive impairment in middle-to-older adults, moderate quality evidence for an association between aircraft noise and reading and language in children, and moderate quality evidence against an association between aircraft noise and executive functioning in children. Generally the literature was supportive for other cognitive outcomes, but with low or very low-quality evidence. Discussion: The evidence so far suggests that noise exposure is associated with cognition, but more good quality research using standardised methodology is required to corroborate these results and to allow for precise risk estimation by larger meta-analyses. There is also a need for more research with older teenagers and young-to-middle aged adults, on the synergistic effects of noise and air pollution, and in Africa, Central and South America, South Asia and Australasia.
... In addition, it has been characterized as an independent predictor of annoyance for urban noise [2]. Coping strategies are strongly associated to the degree of exposure, leading to actions of tuning out unwanted noise events [85]. Age group is also an important factor, considering the developmental period of children as well as the development of coping strategies for stress events, such as noise. ...
... Energy-based indicators, expressing noise exposure in homes, with reference to the indicator L den , and in schools, with reference to the indicator L d or the indicator L e or the indicator L n , showed a significant effect. The latter evidence is in agreement with previous exposure-based studies [7,13,85]. Finally, the association between the L A,eq indicator in terms of road traffic noise exposure and cognitive functioning-based test results indicated the influence of noise exposure on complex tasks [57], which is in accordance with the study [87]. ...
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A systematic literature review was conducted to investigate which objective noise indicators related to various noise sources (i.e., aircraft, road-traffic, and ambient noise) are the best predictors of non-auditory health-effects in children. These relationships are discussed via a conceptual framework, taking into account main parameters such as the type of noise source, the exposure locations and their environments, the type of noise indicators, the children’s mediating factors, and the type of non-auditory health effects. In terms of the procedure, four literature databases were screened and data was extracted on study design, types of noise sources, assessment method, health-based outcomes and confounders, as well as their associations. The quality of the studies was also assessed. The inclusion criteria focused on both indoor and outdoor environments in educational buildings and dwellings, considering that children spend most of their time there. From the 3337 uniquely collected articles, 36 articles were included in this review based on the defined inclusion and exclusion criteria. From the included literature, it was seen that noise exposure, assessed by energetic indicators, has significant associations with non-auditory health effects: psychophysiological, cognitive development, mental health and sleep effects. Percentile and event-based indicators provided significant associations to cognitive performance tasks and well-being dimension aspects.
... This research is closer to showing a causal effect of aircraft noise than the other cross-sectional studies and suggests that the negative effect of noise on cognitive abilities can be reversible. Cross sectional data on noise abatement programs have also shown positive effects on mathematics (Cohen, Krantz, Evans, Stokols, & Kelly, 1981 -for aircraft noise) and reading skills (Bronzaft, 1981 -for railway noise). ...
... The evolution of classroom noise levels, children's reactions to noise, executive functions, and school performance, will be presented in Chapter 7. Physical solutions to the issue of noise have been proposed in the literature. Sound absorbent panels, carpets or ceiling hangings can all absorb noise and reduce reverberation (Berg et al., 1996;Bronzaft, 1981;Cohen et al., 1981;Maxwell & Evans, 2000). This might be particularly useful when schools are exposed to high levels of external noise (e.g., road traffic noise, aircraft noise), and when it is difficult to meet the official requirement of 35dB of background noise in empty classrooms (Education Funding Agency, 2015). ...
Conference Paper
Noise is a prevalent part of primary school. Yet, it is unclear why some pupils are more affected by it than others. Theoretical and empirical evidence suggest that noise impacts learning by deviating attention. This hypothesis has been tested on adult populations using working memory and attention tasks, but not on children. This thesis presents laboratory and school studies filling this gap. Chapter 2 investigates the impact of moderate verbal noise (single-talker noise) and multi-talker classroom noise on reading comprehension, text recall and mathematics performance, among a sample of children in Years 4 to 6. Noise had a detrimental effect on text recall and mathematics, but only when the noisy session was presented before the silent session. There was no difference between the impact of the two types of noise. Inhibitory control was not identified as a protective factor. Better working memory was protective when doing mathematics in noise – but this was not found for reading comprehension and text recall. In Chapter 3, children in Years 1 to 6 were engaged in two idea generation tasks, with or without the presence of moderate multi-talker noise. Noise only had a detrimental impact on the original of ideas for children in Years 1 to 3, and this was evident in only one of the two tasks. Better inhibitory control was protective when generating new ideas in noise, especially for children in Years 1 to 3. Studies from Chapters 2 and 3 provide new insights into the mechanisms underlying the impact of noise. They also reveal a challenge for researchers and educators; namely, that the objective impact of noise on performance does not align with children’s self-reported experience of being distracted. Chapter 4 explores different dimensions of children’s reactions to noise, in a sample of pupils in Years 5 and 6. Here, perceiving noise as interfering with an ongoing activity in the classroom was partly dissociable from feeling annoyed by it. Children who reported greater difficulties in switching from one task to another also reported greater noise interference and annoyance. Children who reported greater mind-wandering reported greater interference, but not annoyance. Chapter 5, based on the same sample, highlighted that behavioural tests of sustained attention and working memory were associated with noise interference, but not annoyance. Together, these results bridge the gap between self-report, and behavioural assessments of distractibility. Finally, Chapters 6 and 7 reported on two separate mindfulness and sound awareness interventions that were co-designed with teachers, and implemented among the same sample as in Chapters 4 and 5. The reduction in noise levels was more important in the sound awareness and in the control groups than in the mindfulness group. Only the sound awareness group was associated with reduced feelings of noise interference and annoyance. Improvements in reading comprehension were more important in the mindfulness group than in the sound awareness group. In conclusion, this thesis shows that the impact of noise on learning and well-being is partly underlined by attentional mechanisms, and suggests practical solutions to reduce children’s negative reactions to noise.
... This is in agreement with Berglund and Lindvall (1995) and the Institute for Environment and Health (1997) who argue that that noise has a detrimental effect upon the learning and performance of primary school children, and that the older children in this age group are more affected than the younger children. Activities affected by noise among pupils include memory, reading, motivation, and attention (Bronzaft 1981;Cohen et al. 1981;Hygge et al. 1996;Berget al. 1996;Maxwell & Evans 2000;Lundquistet al. 2000;Haines et al. 2002;Clark et al. 2006). (k) Play equipment was noted as a source of physical hazards at Sefula Secondary School. ...
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BSTRACT This study proposes a localised approach to school safety and health management, using Sefula secondary school as a case study. In this regard, the aim of this study was to develop a localised school Safety and Health Manual by using ideas and practices of safety and health held by sampled participants of Sefula Secondary School. This aim was operationalised through the following objectives: (a) to assess the state of safety and health at Sefula Secondary School herein used as a case study (b) to establish ideas and practices of safety and health held by sampled participants of Sefula Secondary School (c) to develop a localised school safety and health manual for Sefula Secondary School based on items (a) and (b) above.The study sample consisted of 10 pupils, 7 teachers, 3 auxiliary staff from Sefula secondary school, 5 parents from Sefula community, 1 Education Standards Officer (ESO)from Mongu district education office and 1 Environmental Health Technologist (EHT) from Sefula clinic. Homogeneous purposive sampling was used to sample teachers, pupils and auxiliary staff, expert purposive sampling was used to select EHT and ESO while parents were selected using snow bowling. The study used an intrinsic case study research model. Data was collected using interview schedules, focus group discussion, observation and document review. Qualitative data collected was transcribed and analyzed as an ongoing process as themes and sub themes emerged. Moreover, a manual was proposed arising from the interpreted results, and such a manual reflects idiosyncratic hazards and risks of Sefula secondary school. The main findings showed that, in addition to generally familiar hazards common to such educational institutions, Sefula secondary school had a variety of safety and health concerns unique to that school environment, for example, poor sanitary conditions, floods, bad company, threats posed by the Sefula stream and Sefula forest and so on. The study also deduced that safety and health concerns inherent at this school needed local solutions if they were to be fully managed because some of them were influenced by socio-cultural aspects of the Sefula environment. The study concludes that a localised school safety and health manual is more responsive to the needs of an individual school like Sefula secondary as opposed to a generic manual prepared at national, provincial or district level. This is partly because a localised school safety manual deals with specific safety and health issues peculiar to a particular school. To this effect, the study recommends that individual schools should be allowed to devise their own safety and health manuals to effectively respond to local needs. Key words: Manual, School, School Safety, School Health (16) (PDF) DEVELOPING A LOCALISED SCHOOL SAFETY AND HEALTH MANUAL FOR SEFULA SECONDARY SCHOOL IN WESTERN ZAMBIA. Available from: [accessed Sep 20 2021].
... A study of 9to 10-year-old children from rural Alpine areas. (Haines, Stansfeld, Brentnall, et al. 2001), (Haines, Stansfeld, Job, et al. 2001) (Cohen S, Krantz DS, Evans GW, et al, 1981) and (Lercher, Evans, Meis, 2003) found that modest levels of ambient community noise (train and road traffic noise above 60 dBA) were associated with poorer memory performance, but not with performance on a test of attention. Several studies have suggested that the effects of noise on children's cognition are not uniform across all cognitive tasks: tasks which involve central processing and language comprehension, such as reading, problem solving and memory appear to be most affected by exposure to noise, (Cohen, Evans, Stokols, et al 1986) and (Hygge, Evans, Bullinger, 2002). ...
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This paper describes the recent development on aircraft noise and the health consequences associated as a result of being exposed to it. The results connote that there a strong interference between aircraft noise and adverse health effects that develops as a result of exposure to it. The course of this paper is to analyse the findings that are involved which includes: Environmental Noise, Measurement of Noise, The Concept of Aircraft Noise, Sound production, Mechanism of Sound Production which is divided into three categories namely; Engine and other mechanical noise, Aerodynamic noise, Noise from aircraft systems. Other concepts are; Effects of Aircraft Noise on human health which are; Cardiovascular health effect, sleep disturbance, annoyance, psychological health. Diseases associated with long time exposure to Aircraft Noise include; effects of noise on low birth weight and prematurity, endocrine responses to noise exposure, blood pressure responses to noise exposure, annoyance, noise-Induced hearing loss, noise and sleep disturbance in children, noise and psychological health in children, quality of life and well-being, psychiatric disorders and noise exposure, noise and cognitive impairment in children. Finally, recommendations were made alongside with ways of reducing the effects of noise and control measures.
... To the best of our knowledge, only a few studies have considered academic maths tasks when assessing the impact of environmental noise on students' performance (Cohen, Krantz, Evans, Stokols, & Kelly, 1981;Dockrell & Shield, 2006), and little attention has been paid to verbally-presented maths tasks (i.e., maths tasks in which the problems are presented in the auditory modality). The first studies of this kind were conducted almost fifty years ago (Kassinove, 1972;Johansson, 1983;Zentall & Shaw, 1980), and the results indicated that noise had no effect on children's performance in mentally solving written additions, subtractions, multiplications and divisions, whatever their type or level of difficulty. ...
The main goal of the present research is to gain a better understanding of the consequences of background noise on learning, with a specific focus on how noise may impair maths achievement. A mental calculation task was administered in the classroom to 162 middle-school students (11 to 13 years old). The listening conditions were manipulated, choosing three different conditions - quiet, traffic and classroom noise - to reflect realistic noise exposure experienced in urban classrooms. A differential negative effect of listening condition on maths performance emerged in relation to task difficulty and children’s age. The youngest children performed better in the quiet and traffic noise conditions than in the classroom noise condition, while in the older children these differences gradually disappeared. The detrimental effect of classroom noise was most evident when the maths task was moderately difficult. With increasing task complexity, the difference between listening conditions faded. These data support the idea that younger children are more susceptible to the detrimental effects of noise in school classrooms than older children, and that their academic attainments are affected. Our findings have implications for classroom learning because different types of environmental noise affected children’s performance differently, depending on the complexity of the task in hand.
This chapter provides a systematic overview of the existing evidence investigating the health effects of environmental noise. There is now considerable scientific literature linking environmental noise exposure with a wide array of negative health effects. The most significant of these are annoyance and sleep disturbance, and a range of cardiovascular outcomes such as hypertension and ischaemic heart disease. Other emerging effects include myocardial infarction (heart attack), stroke, adverse birth and fertility issues as well as tentative links with various cancers. Moreover, the after-effects of noise-induced sleep disturbance are associated with numerous health-related problems including fatigue, reduced cognitive and physical performance, increased anxiety and negative emotional states such as anger and depression. Children appear to be a particular risk group with respect to noise with research showing that environmental noise exposure negatively impacts cognition in children. These negative impacts include reduced reading and problem-solving ability as well as reduced attention span and motivation among noise-exposed children. Moreover, the most recent evidence suggests a link with mental health issues including emotional problems, conduct disorder, hyperactivity and antisocial behaviour.
Whilst the effects of aircraft noise on children's cognition are well-accepted, their application in Health Impact Assessment (HIA) and methodologies to monetise the effects of noise on health have been limited. This paper presents the first meta-analysis of the effect of aircraft noise at school on children's reading comprehension and psychological health assessed with the Strengths and Difficulties Questionnaire. Data from three methodologically similar studies carried out in 106 schools near London Heathrow, Amsterdam Schiphol, and Madrid Barajas airports (the Schools Environment and Health Study, the West London Schools Study, and the RANCH study) were analysed finding that a 1 dB increase in aircraft noise exposure at school was associated with a −0.007 (−0.012 to −0.001) decrease in reading score and a 4% increase in odds of scoring well below or below average on the reading test. The analyses also found that a 1 dB increase in aircraft noise exposure at school was associated with a 0.017 (0.007–0.028) increase in hyperactivity score. No effects were observed for emotional symptoms, conduct problems or Total Difficulties Score. Meta-analyses confirm existing evidence for effects of aircraft noise exposure on children's reading comprehension, providing a pooled estimate and exposure-effect relationship, as well as additional estimates and relationships for effects on scoring ‘well below or below average’ on the reading test offering flexibility for taking reading comprehension into account in HIA and monetisation methodologies in a wide-range of contexts.
Introduction.- Vector and Matrix Algebra.- The Multivariate Normal Distribution, Multivariate Normality, and Covariance Structure.- One- and Two-Sample Tests.- Multivariate Analysis of Variance.- Discriminant Analysis.- Canonical Correlation.- Principal Component Analysis.- Factor Analysis.- Structural Equations.
Book on noise effects on man covering audiometry, aural reflex, hearing damage risk, physiological responses, motor performance and speech communication
Results from a variety of studies suggest that under conditions of arousal and/or information overload, attention is focused on task-relevant cues at the cost of those that are less relevant to task performance. The stimuli under consideration in these studies have been exclusively nonsocial. To examine the effects of environmental stress on the processing of task-irrelevant cues of a social nature, subjects performed a free recall task in which they were instructed to recall six nonsense syllables presented serially under either noise or quiet. In all conditions, slides of social situations, each depicting either calm or distressed person(s), were presented just to the right of the nonsense syllables. After simulus presentation half of the subjects were given the expected recall test for nonsense syllables. The remaining subjects were instead given a recognition memory test for the peripheral social cues. While noise did not affect memory for the task-relevant cues (nonsense syllables), task-irrelevant cues (social-cue slides), regardless of whether they depicted calm or distressed persons, were remembered less well under noise than under quiet.
This study examined the relationship between a child's auditory and verbal skills and the noisiness of his home. Expressway traffic was the principal source of noise. Initial decibel measurements in a high-rise housing development permitted use of floor level as an index of noise intensity in the apartments. Children living on the lower floors of 32-story buildings showed greater impairment of auditory discrimination and reading achievement than children living in higher-floor apartments. Auditory discrimination appeared to mediate an association between noise and aeading deficits, and length of residence in the building affected the magnitude of the correlation between noise and auditory discrimination. Additional analyses ruled out explanations of the auditory discrimination effects in terms of social class variables and physiological damage. Partialling out social class did, however, somewhat reduce the magnitude of the relationship between noise and reading deficits. Results were interpreted as documenting the existence of long-term behavioral aftereffects in spite of noise adaptation. Demonstration of postnoise consequences in a real-life setting supplement laboratory research showing the stressful impact of noise on behavior.
Blood pressure, height, weight, maturation, triceps skinfold thickness, serum lipids, and hemoglobin were measured as risk factors for coronary artery disease in 3,524 children (93% of the eligible population) in Bogalusa, Louisiana. Nine blood pressures were taken on each child by trained observers with mercury sphygmomanometers (Baumanometer) and Physiometrics automatic recorders in a rigid randomized design in a relaxed atmosphere with other children present. The pressures observed were low compared to reported data. Black children had significantly higher blood pressures than white children. This difference, starting before age 10, was largest in the children in the upper five percent of the pressure ranks. Stepwise multiple regression analysis revealed that this racial differnce was significant when measured by an automatic recorder. Body size, expressed by height and by weight/height3 index, was a strong determinant of blood pressure level. Other positive determinants were blood hemoglobin and external maturation.
An overview of the effects of noise on people as can be determined from the scientific literature is presented. Only audible noise is considered and no attempt is made to describe the extent of the noise problem in terms of the number of people affected or in terms of social and economic costs. Rather, emphasis is placed on describing and classifying the adverse effects and relating them in a general way to the intensive and temporal properties of audible noise. For simplicity, the intensive dimension of the noise is usually given as the A weighted sound level and detailed descriptions and evaluations of various acoustical measurements are for the most part avoided. The effects of noise are classified as auditory, general psychological and sociological, or as general physiological.
In this study, indoor and outdoor measurements of jet aircraft noise were made at 7 schools beneath the eastern approach paths to the Los Angeles International Airport. At 5 elementary schools, the jet noise in the schoolyards ranged from 96 to 118 dBC and constituted a high risk of hearing damage for the children. The frequency of jet aircraft overflights averages one per 2 min interval for a total of about 200 per school day. The corresponding jet noise levels in the classrooms (80% of which are not air conditioned or acoustically treated) ranged from 80 to 96 dBA and caused continual disruption of communication and the learning processes. An investigation of aircraft operation alternatives indicated that the noise could be reduced by 10 dB or more if engine power were properly managed when the aircraft approaches the school areas, or if the aircraft approached at higher altitudes and landed further to the west on the unused 6000 ft long portion of the 12,000 ft long runways.