The effect of noise exposure on human performance and behavior continues to be a focus for research activities. This paper reviews developments in the field over the past 3 years, highlighting current areas of research, recent findings, and ongoing research in two main research areas: Field studies of noise effects on children's cognition and experimental studies of auditory distraction. Overall, the evidence for the effects of external environmental noise on children's cognition has strengthened in recent years, with the use of larger community samples and better noise characterization. Studies have begun to establish exposure-effect thresholds for noise effects on cognition. However, the evidence remains predominantly cross-sectional and future research needs to examine whether sound insulation might lessen the effects of external noise on children's learning. Research has also begun to explore the link between internal classroom acoustics and children's learning, aiming to further inform the design of the internal acoustic environment. Experimental studies of the effects of noise on cognitive performance are also reviewed, including functional differences in varieties of auditory distraction, semantic auditory distraction, individual differences in susceptibility to auditory distraction, and the role of cognitive control on the effects of noise on understanding and memory of target speech materials. In general, the results indicate that there are at least two functionally different types of auditory distraction: One due to the interruption of processes (as a result of attention being captured by the sound), another due to interference between processes. The magnitude of the former type is related to individual differences in cognitive control capacities (e.g., working memory capacity); the magnitude of the latter is not. Few studies address noise effects on behavioral outcomes, emphasizing the need for researchers to explore noise effects on behavior in more detail.
Keywords: Auditory distraction, cognition, epidemiology, noise, transportation
|How to cite this article:|
Clark C, Sörqvist P. A 3 year update on the influence of noise on performance and behavior. Noise Health 2012;14:292-6
| Background|| |
The effect of noise exposure on human performance and behavior continues to be a focus for research activities. The effect of environmental noise exposure on children's cognitive performance and learning has been researched since the early 1970s. In recent years, the effect of chronic noise exposure on children's cognition has been examined by methodologically robust epidemiological studies, whilst the effect of acute noise exposure has been examined in experimental studies. The aim of this research is to inform guidelines for external environmental noise exposure and the planning of school, office, and residential environments, as well as to inform the design of the internal acoustic environment and interventions that might improve performance and learning in schools, as well as productivity in offices. Recent advancements in the field include the use of larger-scale epidemiological community samples and better characterization of noise measurement. This paper highlights some of the recent developments in the field of noise effects on performance and behavior over the past 3 years summarizing developments in field studies of noise effects on children's cognitive performance and in experimental studies of auditory distraction.
| Recent Research|| |
Epidemiological studies of noise effects on cognitive performance
Overall, evidence for the effects of noise on children's cognition has strengthened in recent years.  Several studies have demonstrated that children exposed to chronic aircraft noise exposure at school have poorer reading ability, memory, and school performance on nationally standardized tests than children who are not exposed. ,,,,,,,,, Most research has been carried out in primary school children aged between 5 and 12 years. However, the evidence is predominantly cross-sectional, with evidence from longitudinal studies only beginning to emerge. , Studies have begun to examine exposure-effect relationships, to identify thresholds for noise effects on health and cognition, which can be used to inform guidelines for noise exposure. 
The RANCH project (Road Traffic Noise and Aircraft Noise Exposure and Children's Cognition and Health), the largest study of noise and children's cognition undertaken to date, examined the effects of aircraft noise and road traffic noise exposure at primary school on the cognitive performance of 2844 9-10 year old children attending 89 schools around Heathrow (London), Schiphol (Amsterdam), and Barajas (Madrid) airports finding linear exposure-effect relationships between aircraft noise exposure at school and children's reading comprehension and recognition memory. ,, A further paper at the conference presented preliminary findings of a follow-up study of the UK cohort in secondary school, one of the first longitudinal studies of its type, which suggested a trend for both aircraft noise exposure at primary school and secondary school to be associated with poorer reading comprehension assessed at 15 and 16 years of age.  Further longitudinal studies on large-scale samples remain a research priority.
The Federal Interagency Committee on Aviation Noise (FICAN) funded a pilot study that assessed the relationship between aircraft noise reduction and standardized test scores. , The study evaluated whether abrupt aircraft noise reduction within classrooms, caused either by airport closure or newly implemented sound insulation, was associated with improvements in test scores, in 35 public schools near three US airports in Illinois and Texas. This study is one of the only recent studies to examine the effectiveness of school sound insulation programs as few intervention studies have been carried out. , Overall, this study found some evidence for effects of aircraft noise reduction and improved test results, although some associations were null and some associations were not in the direction hypothesized. This was a pilot study and the authors stress that the airports and schools selected for the study may not be representative and that further, larger studies are required. A larger scale study of this nature is currently ongoing funded by the Aviation Cooperative Research Program.
Several pathways for effects of chronic noise exposure on children's cognition have been suggested including teacher and pupil frustration,  learned helplessness,  impaired attention, , increased arousal,  indiscriminate filtering out of noise during cognitive activities resulting in loss of focused attention/concentration,  noise annoyance, and sleep disturbance.  A recent secondary analysis of night-time noise exposure in the cross-sectional Munich and RANCH study datasets found that self-reported sleep disturbance did not mediate the association of aircraft noise exposure and cognitive impairment in children.  In the RANCH sample, whilst night-time aircraft noise exposure at the child's home was associated with impaired reading comprehension and recognition memory, night-time aircraft noise had no additional effect on these cognitive outcomes, once day-time noise exposure had been taken into account. These findings suggest that the school should be the main focus for the protection of children against the effects of aircraft noise on children's performance. 
Recent years have seen research begin to explore the link between internal classroom acoustics and children's learning outcomes. ,,,,,,, These studies typically focus upon noise interference with verbal communication as the mechanism for the effect: Some studies simply describe the acoustic characteristics of classrooms, some specifically assess speech intelligibility, and a few relate acoustic conditions to performance outcomes such as individually completed cognitive tests, as well as nationally standardized tests.  At the conference, an ongoing study, the ISESS project (Identifying a Sound Environment for Secondary Schools) - a 3-year project investigating the effects on teaching and learning of different acoustic designs within secondary schools and classrooms in the United Kingdom was presented.  This study will build knowledge as it focuses on secondary school rather than primary school children.
A further paper at the conference reported on the World Health Organisation's Burden of Disease from Environmental Noise project,  estimating that for children's cognitive performance, 45,036 disability-adjusted life years are lost each year in the Europe A region, for children aged between 7 and 19 years due to environmental noise exposure.  This compares with 61,000 years for ischaemic heart disease, 654,000 years for noise annoyance, and 903,000 years for sleep disturbance. 
Experimental studies of noise effects on cognitive performance
Functional differences between types of auditory distraction
During the past 3 years, a set of theoretically interesting findings have been reported in the literature. One theoretical debate has concerned whether the effect of sound on serial recall is caused by a conflict between serial order processes or whether it is caused by attentional capture. To address this question, let us consider the difference between the following two effects. The sound sequence "k l m v r q c" is more distracting to serial recall than is the sound sequence "c c c c c c c." This finding is called the changing-state effect., An auditory event that stands out or deviates from the recent auditory past, such as the sound "m" in the sound sequence "c c c m c c c," also disrupts serial recall. This phenomenon is known as the deviation effect., In a set of recent experiments, Jones, Hughes, and colleagues , have shown that the two effects are caused by separate mechanisms. Based on this work, Hughes et al.  have proposed a duplex-mechanism account of auditory distraction whereby the changing-state effect is the result of interference between order processes whereas the deviation effect is caused by attentional capture. Sound, it seems, can impair cognitive performance in two functionally different ways: Either by interfering with the deliberate processes that are engaged in the focal task or by interrupting the execution of the processes (but see  ).
Semantic auditory distraction
The role played by the semantic properties of speech has until recently been somewhat elusive. Older studies have provided conflicting results, some suggesting that disruption is larger when task-irrelevant speech is semantically related to the target material , whereas other studies suggest that disruption is solely a result of the physical properties of the sound. , Recently, however, Marsh and colleagues , have shown that when the focal task requires semantic processing (e.g., retrieving items on the basis of their meaning) the semanticity of irrelevant speech is more disruptive than the sound's acoustic properties. Marsh and colleagues have employed an experimental paradigm whereby each experimental trial involves visually-presented to-be-recalled exemplars that are members of the same semantic category (e.g., fruit). During some trials, the participants are also presented with to-be-ignored spoken words that are either taken from the same semantic category as the to-be-recalled items (e.g., other fruit) or from a different semantic category (e.g., tools). In this paradigm, recall is poorer in the semantically related condition, but only when the participants are allowed to recall the items in free order. This finding is called the between-sequence semantic similarity effect. Marsh and colleagues have interpreted these findings within an interference-by-process approach to auditory distraction, similar to that applied to the changing-state effect. , Semantic auditory distraction appears to be caused by deliberate inhibition of nontarget competitors-activated by speech-that spreads to target items and thus impairs recall.
Individual differences in susceptibility to auditory distraction
The reason why people differ in susceptibility to auditory distraction has also been debated during the past 3 years. This debate has mainly concerned whether auditory distraction can be overruled by cognitive control. In support of a role for cognitive control in auditory distraction, Sörqvist and colleagues ,,,, have shown that individuals with high working memory capacity (WMC) are generally less susceptible to auditory distraction. This conclusion is consistent with the notion that older individuals, who are known to be more lenient in cognitive control generally, are more susceptible to the effects of speech on prose memory.  However, the conclusion is qualified by an intriguing finding. High-WMC individuals are less susceptible to the deviation effect, but not to the changing-state effect.  It appears, therefore, as if some but not all types of auditory distraction can be overruled by cognitive control, supporting a duplex-mechanism account of auditory distraction.
Applied experimental research
Most applied experimental research in the past has concerned noise in schools. Effects of noise in other environments, like open-plan offices, have been relatively neglected. In recent years, however, several open-plan office studies have been reported. ,, These investigations have shown that noise does indeed impair work related performance, just as in schools, and some of these effects may be attenuated by applying masking sound. Another area that has been quite neglected in the past is how noise impairs memory of spoken information. In a series of recent experiments, however, Kjellberg, Ljung, and colleagues ,, have shown that low signal-to-noise ratio and reverberation impairs memory of spoken materials in comparison with better listening conditions, even when the participants can hear what is said. The general conclusion from this line of research is that classroom acoustics should, at least in part, be evaluated by applying a memory criterion (i.e. how much the pupils can remember from what they hear) rather than a comprehension criterion.
| Future Research Directions|| |
The European Network on Noise and Health (ENNAH) recently published recommendations for future research needs in the field of noise effects on cognition (see www.ennah.eu). These recommendations suggest that to understand the causal pathways between aircraft noise exposure and cognition, and design preventive interventions there is a need to study the associations longitudinally. Another area where knowledge is lacking concerns the question of what can be done to reduce noise-induced learning impairments; there has been little research testing whether sound insulation of classrooms might lessen the effects of aircraft noise on children's learning. It was also suggested that future studies should examine a range of additional noise metrics such as the number of noise events and peak sound events to assess their associations with children's cognitive performance. Finally, whilst recent evidence of exposure-effect relationships between aircraft noise exposure and children's cognition has provided knowledge about thresholds for effects, further examination of exposure-effect relationships in different contexts, for different samples, and for different noise metrics remains a research priority.
We would like to take the opportunity to request two lines of laboratory studies that could prove fruitful in the future. Laboratory studies could investigate how the spatial distribution of the irrelevant sound sources and the target materials influence auditory distraction. This line of study could further elucidate functional differences between various forms of auditory distraction and how the two hemispheres of the brain process sound differently. Moreover, knowledge in this realm would enhance our understanding of how to build classrooms and offices with optimal sound distribution. Moreover, most experimental studies use tasks wherein participants are (often visually) presented with some material and asked to remember it for later recall, to make inferences or to do some other cognitive operation with the material presented. Very few studies have looked at the effects of noise on tasks whereby the participants produce materials themselves,  even though production tasks such as writing are very common in school and office settings. Future studies should further investigate the effects of noise on writing and similar tasks.
At this time, there remains a lack of studies of noise effects on behavior. A recent systematic review  highlighted studies that have found that loud noise exposure in bars and nightclubs is associated both with increased aggressive behavior as well as with intoxication. Such studies illustrate links between noise exposure and behavior that have important public health implications. In terms of behavioral outcomes, one conference paper reported on an increased risk of accidents and injuries at work with occupational noise exposure  and another examined the role of intensive care unit noise on nurses' behavior  but overall, few studies addressed behavioral outcomes, reinforcing the need for the field to identify and explore noise effects on behavior in more detail.
| References|| |
|1.||Evans GW, Hygge S. Noise and performance in children and adults, Noise and its effects. In: Luxon L, Prasher D, editors. London: Whurr Publishers; 2007. |
|2.||Bronzaft AL. The effect of a noise abatement program on reading ability. J Environ Psychol 1981;1:215-22. |
|3.||Bronzaft AL, McCarthy DP. The effects of elevated train noise on reading ability. Environ Behav 1975;7:517-27. |
|4.||Clark C, Martin R, van Kempen E, Alfred T, Head J, Davies HW, et al. Exposure-effect relations between aircraft and road traffic noise exposure at school and reading comprehension: The RANCH project. Am J Epidemiol 2006;163:27-37. |
|5.||Cohen S, Glass DC, Singer JE. Apartment noise, auditory discrimination, and reading ability in children. J Exp Soc Psychol 1973;9:407-22. |
|6.||Eagan ME, Anderson G, Nicholas B, Hornojeff R, and Tivnan T. Relation between aircraft noise reduction in schools and standardized test scores. Washington, DC: FICAN; 2004. |
|7.||Evans GW, Hygge S, Bullinger M. Chronic noise and psychological stress. Psychol Sci 1995;6:333-8. |
|8.||Evans GW, Maxwell L. Chronic noise exposure and reading deficits: The mediating effects of language acquisition. Environ Behav 1997;29:638-56. |
|9.||Haines MM, Stansfeld SA, Brentnall S, Head J, Berry B, Jiggins M, et al. The West London Schools Study: The effects of chronic aircraft noise exposure on child health. Psychol Med 2001;31:1385-96. |
|10.||Haines MM, Stansfeld SA, Job RF, Berglund B, Head J. Chronic aircraft noise exposure, stress responses, mental health and cognitive performance in school children. Psychol Med 2001;31:265-77. |
|11.||Haines MM, Stansfeld SA, Head J, Job RF. Multilevel modelling of aircraft noise on performance tests in schools around Heathrow Airport London. J Epidemiol Community Health 2002;56:139-44. |
|12.||Stansfeld SA, Berglund B, Clark C, Lopez-Barrio I, Fischer P, Ohrström E, et al. Aircraft and road traffic noise and children's cognition and health: A cross-national study. Lancet 2005;365:1942-9. |
|13.||Matheson M, Clark C, Martin R, van Kempen E, Haines M, Barrio IL, et al. The effects of road traffic and aircraft noise exposure on children's episodic memory: The RANCH project. Noise Health 2010;12:244-54. |
|14.||FICAN, Findings of the FICAN pilot study on the relationship bn aircraft noise reduction and changes in standardised test scores. Washington, DC: FICAN; 2007. |
|15.||Cohen S, Krantz DS, Evans GW, Stokols D, Kelly S. Aircraft noise and children: Longitudinal and cross-sectional evidence on adaptation to noise and the effectiveness of noise abatement. J Pers Soc Psychol 1981;40:331-45. |
|16.||Evans G, Lepore S. Non-auditory effects of noise on children: A critical review. Child Environ 1993;10:42-72. |
|17.||Evans GW, Stecker R. Motivational consequences of environmental stress. J Environ Psychol 2004;24:143-65. |
|18.||Yerkes RM, Dodson JD. The relation of strength of stimulus to rapidity of habit formation. J Comp Neurol Psychol 1908. 18: p. 459-482. |
|19.||Cohen S, Evans GW, Krantz DS, and Stokols D. Behavior, Health and Environmental Stress. New York: Plenum Press; 1986. |
|20.||HCN. The influence of night-time noise on sleep and health (2004/14E). Health Council of the Netherlands: The Hague; 2004. |
|21.||Stansfeld S, Hygge S, Clark C, Alfred T. Night time aircraft noise exposure and children's cognitive performance. Noise Health 2010;12:255-62. |
|22.||Astolfi A, Pellerey F. Subjective and objective assessment of acoustical and overall environmental quality in secondary school classrooms. J Acoust Soc Am 2008;123:163-73. |
|23.||Bradley JS, Sato H. The intelligibility of speech in elementary school classrooms. J Acoust Soc Am 2008;123:p. 2078-2086. |
|24.||de Oliveira Nunes MF, Sattler MA. Aircraft noise perception and annoyance at schools near Salgado Filho International Airport. Brazil J Build Acoust 2006;13:159-72. |
|25.||Dockrell JE, Shield BM. Children's perceptions of their acoustic environment at school and at home. J Acoust Soc Am 2004;115:2964-73. |
|26.||Dockrell JE, Shield BM. Acoustical barriers in classrooms: The impact of noise on performance in the classroom. Br Educ Res J 2006;32:509-25. |
|27.||Shield BM, Dockrell JE. External and internal noise surveys of London primary schools. J Acoust Soc Am 2004;115:730-8. |
|28.||Shield BM, Dockrell JE. The effects of environmental and classroom noise on the academic attainments of primary school children. J Acoust Soc Am 2008;123:133-44. |
|29.||Sato H, Bradley JS. Evaluation of acoustical conditions for speech communication in working elementary school classrooms. J Acoust Soc Am 2008;123:2064-77. |
|30.||Dockrell JE, Shield BM. Noise in secondary schools: Pupils' perceptions and performance, in International Congress on the Biological Effects of Noise. London, 2011. |
|31.||WHO, Burden of disease from environmental noise. Copenhagen, Europe: World Health Organisation; 2011. |
|32.||Hygge S. Noise effects on children's cognition - WHO work on noise, burden of diseases (BoD) and disability-adjusted life years (DALY), in International Congress on the Biological Effects of Noise.: London, 2011. |
|33.||Macken WJ, Phelps FG, Jones DM. What causes auditory distraction? Psychol Bull Rev 2009;16:139-44. |
|34.||Jones DM, Macken WJ. Irrelevant tones produce an irrelevant speech effect: Implications for phonological coding in working memory. J Exp Psychol Learn Mem Cogn 1993;19:369-81. |
|35.||Hughes RW, Vachon F, Jones DM. Disruption of short-term memory by changing and deviant sounds: Support for a duplex-mechanism account of auditory distraction. J Exp Psychol Learn Mem Cogn 2007;33:1050-61. |
|36.||Hughes RW, Vachon F, Jones DM. Auditory attentional capture during serial recall: Violations at encoding of an algorithm-based neural model? J Exp Psychol Learn Mem Cogn 2005;31:736-49. |
|37.||Perham N, Banbury SP, Jones DM. Reduction in auditory distraction by retrieval strategy. Memory 2007;15:465-73. |
|38.||Bell R, Dentale S, Buchner A, Mayr S. ERP correlates of the irrelevant sound effect. Psychophysiology 2010;47:1182-91. |
|39.||Neely CB, LeCompte DC. The importance of semantic similarity to the irrelevant speech effect. Mem Cognit 1999;27:37-44. |
|40.||Oswald CJ, Tremblay S, Jones DM. Disruption of comprehension by the meaning of irrelevant sound. Memory 2000;8:345-50. |
|41.||Buchner A, Irmen L, Erdfelder E. On the irrelevance of semantic information for the "irrelevant speech" effect. Q J Exp Psychol 1996;49A:765-79. |
|42.||Tremblay S, Nicholls AP, Alford D, Jones DM. The irrelevant sound effect: Does speech play a special role? J Exp Psychol Learn Mem Cognit 2000;26:1750-4. |
|43.||Marsh JE, Hughes RW, Jones DM. Auditory distraction in semantic memory: A process-oriented approach. J Mem Lang 2008;58:682-700. |
|44.||Sörqvist P. The role of working memory capacity in auditory distraction: A review. Noise Health 2010;12:217-24. |
|45.||Marsh JE, Hughes RW, Jones DM. Interference by process, not content, determines semantic auditory distraction. Cognition 2009;110:23-38. |
|46.||Sörqvist P. Effects of aircraft noise and speech on prose memory: What role for working memory capacity? J Environ Psychol 2010;30: 112-118. |
|47.||Sörqvist P. High working memory capacity attenuates the deviation effect but not the changing-state effect: Further support for the duplex-mechanism account of auditory distraction. Mem Cognit 2010;38:651-8. |
|48.||Sörqvist P, Halin N, Hygge S. Individual differences in susceptibility to the effects of speech on reading comprehension. Appl Cognit Psychol 2010;24:67-76. |
|49.||Sörqvist P, Ljungberg JK, Ljung R. A sub-process view of working memory capacity: Evidence from effects of speech on prose memory. Memory 2010;18:310-26. |
|50.||Bell R, Buchner A, Mund I. Age-related differences in irrelevant-speech effects. Psychol Aging 2008;23:377-91. |
|51.||Haapakangas A, Kankkunen E, Hongisto V, Virjonen P, Oliva D, Keskinen E. Effects of five speech masking sounds on performance and acoustic satisfaction. Implications for open-plan offices. Acta Acoust United Acoust 2011;97:641-55. |
|52.||Jahncke H, Hygge S, Halin N, Green A, and Dimberg K. Open-plan office noise: Cognitive performance and restoration. J Environ Psychol 2011; 31: 373-382. |
|53.||Liebl A, Haller J, Jödicke B, Baumgartner H, Schlittmeier S, Hellbrück J. Combined effects of acoustic and visual distraction on cognitive performance and well-being. Appl Ergon 2012;43:424-34. |
|54.||Kjellberg A, Ljung R, Hallman D. Recall of words heard in noise. Appl Cognit Psychol 2008;22:1088-98. |
|55.||Ljung R, Kjellberg A. Long reverberation time decreases recall of spoken information. Build Acoust 2009;16:301-12. |
|56.||Ljung R, Sörqvist P, Kjellberg A, and Green AM. Poor listening conditions impair memory of intelligible lectures: Implications for acoustic classroom standards. Build Acoust 2009;16:257-65. |
|57.||Sörqvist P, Nöstl A, Halin N. Disruption of writing processes by the semanticity of background speech. Scand J Psychol 2012;53:97-102. |
|58.||Hughes K, Quigg Z, Eckley L, Bellis M, Jones L, Calafat A, et al. Environmental factors in drinking venues and alcohol-related harm: The evidence base for European Intervention. Addiction 2011;106:37-46. |
|59.||Smith AP. Effects of noise, job characteristics and stress on mental health and errors at work. London: In International Congress on the Biological Effects of Noise; 2011. |
|60.||Ryherd EE, Okcu S, Hsu1 T, Zimring C, Persson Waye K. Impact of Intensive Care Unit noise on nurses. London: In International Congress on the Biological Effects of Noise; 2011. |
Senior Lecturer Environmental and Mental Health Epidemiology, Centre for Psychiatry, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Old Anatomy Building, Charterhouse Square, London EC1M 6BQ