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ARTICLE Table of Contents   
Year : 2009  |  Volume : 11  |  Issue : 45  |  Page : 194-198
Effects of road traffic noise and irrelevant speech on children's reading and mathematical performance

Laboratory of Applied Psychology, Centre for Built Environment, University of Gävle, Sweden

Click here for correspondence address and email
Date of Web Publication2-Oct-2009

Irrelevant speech in classrooms and road traffic noise adjacent to schools have a substantial impact on children's ability to learn. Comparing the effects of different noise sources on learning may help construct guidelines for noise abatement programs. Experimental studies are important to establish dose-response relationships and to expand our knowledge beyond correlation studies. This experiment examined effects of road traffic noise and irrelevant speech on children's reading speed, reading comprehension, basic mathematics, and mathematical reasoning. A total of 187 pupils (89 girls and 98 boys), 12-13 years old, were tested in their ordinary classrooms. Road traffic noise was found to impair reading speed (P < 0.01) and basic mathematics (P < 0.05). No effect was found on reading comprehension or on mathematical reasoning. Irrelevant speech did not disrupt performance on any task. These findings are related to previous research on noise in schools and the implications for noise abatement guidelines are discussed.

Keywords: Children, irrelevant speech, mathematics, reading comprehension, reading speed, road traffic noise

How to cite this article:
Ljung R, Sorqvist P, Hygge S. Effects of road traffic noise and irrelevant speech on children's reading and mathematical performance. Noise Health 2009;11:194-8

How to cite this URL:
Ljung R, Sorqvist P, Hygge S. Effects of road traffic noise and irrelevant speech on children's reading and mathematical performance. Noise Health [serial online] 2009 [cited 2018 Aug 15];11:194-8. Available from: http://www.noiseandhealth.org/text.asp?2009/11/45/194/56212

  Introduction Top

The American National Standards Institute emphasizes that school buildings' sound isolation should prevent two types of noise: noise that intrudes into the classroom from sources outside of the school building envelope, which include vehicular traffic, aircrafts, industrial plants, and activity in schoolyards and noise that originates within the school building such as unwanted speech. [1] The present investigation aimed to compare the effects of road traffic noise and irrelevant speech on cognitive performance in schools.

A range of epidemiological studies have shown that noise has negative effects on memory and learning, e.g. Hygge, Evans and Bullinger [2] performed a prospective longitudinal study on children during the switchover from Munich's old airport to the new Munich International Airport. Their results showed that chronic aircraft noise impaired reading and long-term memory. Another more recent cross-national epidemiological study is the Road traffic and Aircraft Noise exposure and children's Cognition and Health (RANCH) project. In this project, Clark et al.[3] compared the effects of chronic exposure to aircraft noise and road traffic noise on reading comprehension. A total of 2844 pupils around Amsterdam Schiphol, Madrid Barajas, and London Heathrow participated in the study. Aircraft noise exposure was negatively correlated with children's reading comprehension (this findings was still statistically significant after adjustments for socioeconomic variables). Road traffic noise showed no significant effect on reading comprehension. However, another paper from the same project found that road traffic noise exposure was linearly associated with performance on an episodic memory task. [4] For a more detailed account of chronic transport noise effects see Clark and Stansfeld. [5]

Studies of chronic noise exposure are important to our understanding of the relationship between noise and school performance. Unfortunately, such studies always have to deal with confounding variables. The fact that poorer quality schools are more common in socially deprived areas, which are also more likely to be exposed to high levels of noise, [6] means that such studies often have problems with confounding variables like socioeconomic background and social deprivation. A statistical adjustment may decrease the confounding effect, but the confounding variables do not vanish. One way to attenuate the influence from confounding variables is to run experimental studies.

The effects of noise exposure on children's cognitive performance have also been addressed in experimental investigations. [7],[8],[9] During the past 5 years, several investigations have compared the effect of road traffic noise and irrelevant speech on children's school performance. For example, Hygge, Boman and Enmarker [10] found both road traffic noise and meaningful irrelevant speech to impair children's delayed memory of a text. Further, Boman [11] reported a disruptive effect of irrelevant speech on children's memory of a text. However, the authors of these investigations did not control for children's immediate reading comprehension. Hence, the effects of noise on text retention could rather be an effect of impaired comprehension. The present study aimed to fill this gap by comparing the effects of road traffic noise and irrelevant speech on children's immediate reading comprehension.

Johansson [12] measured reading comprehension and reading speed by letting 10-year-old children read short stories under silence (25 dB) and two octave band noise conditions (continuous noise at 51 dB or intermittent noise at 55-78 dB). At certain stages in each story the children had to underline one out of three words to make the story comprehensible. The results revealed no main effects of noise, neither on reading comprehension nor on reading speed, but children with low intelligence were more affected by noise than children with high intelligence. Studies of adults have found that performance on language-based tasks that involve semantic processing such as reading comprehension [13],[14],[15] and proofreading [16],[17] are particularly affected by sounds with semantic meaning (i.e., speech). This is well in-line with studies of more basic cognitive processes, such as attentional processes involved in the retention of information in short-term memory. [18],[19] Against this background, it is likely that Johansson would have obtained a main effect of noise if he had included speech as a noise source. Consistent with this assumption, Boman [11] found irrelevant speech to disturb children's performance on a word comprehension test, whereas the effect of road traffic noise failed to reach significance. The same result could be expected for children's reading comprehension. This hypothesis is tested in the present investigation.

Shield and Dockrell [20] performed an innovative study where they examined both acute and chronic noise exposure. They showed that chronic exposure to both external and internal noise has a negative impact upon the academic performance and attainments of primary school children. For external noise, it appears to be the noise levels of individual events that have the most impact, while background noise in the classroom also has a significant disruptive effect. Older primary school children, around 11 years of age, appear to be more affected by noise than the younger children. Classroom babble was found to decrease performance on both verbal and nonverbal tasks, with verbal tasks of reading and spelling being particularly affected, which is in-line with the interference-by-process view described by Marsh, Hughes and Jones. [18],[19]

The effects of noise on children's arithmetic performance have been subject to rather few investigations. This is somewhat surprising given the significance of mathematics in school education. The present study therefore aimed to compare the effects of road traffic noise and irrelevant speech on mathematical performance. Kassinove [21] tested the effects of four noise sources with or without semantic content on children's ability to solve addition or division problems. He analyzed mean time per response, variability of response time, probability of error, number of correct responses, number of "time-outs," and changes in these behaviors over time and found no effects of noise whatsoever. But later investigations in the area of arithmetic have shown diverse results. Zentall and Shaw [22] compared the effects of high-level noise (continuous fragments of meaningful irrelevant speech at 69 dB) with that of low-level noise (infrequent fragments of meaningful irrelevant speech at 64 dB). No overall effect of noise was found, but hyperactive children performed worse in high-level noise in comparison to low-level noise, while controls showed the opposite pattern. Similarly, Johansson [12] found that children with high intelligence performed better on an arithmetic task under noise than in silence, whereas the opposite pattern was found for children with low intelligence. In a more recent investigation, Dockrell and Shield [23] tested children's arithmetic performance under three background conditions (silence, children babble, and children babble with environmental noise). Performance was better in silence than under exposure to children babble. However, performance in the "children with environmental noise"-condition did not differ from performance under the other two background conditions.

The tasks used by Kassinove, [21] Zentall and Shaw, [22] Johansson [12] , and Dockrell and Shield [23] were all restricted to arithmetic calculations (addition, subtraction, division, and multiplication). However, mathematical problems can also be represented in a word form. Solving such mathematical reasoning problems requires the equation to be constructed from the meaning of the words and is a rather complex task. Some results lean toward the possibility that complex tasks are particularly sensitive to disturbance from noise. [24] Hence, effects of noise on mathematical reasoning tasks can also be expected.

The present experiment had three purposes. First, it aimed to compare the effects of road traffic noise and irrelevant speech on children's reading comprehension and reading speed. Secondly, it aimed to compare the effects of these noise sources on children's basic mathematics; and thirdly, on children's performance on a mathematical reasoning task.

  Method Top

Participants and basic design

Nine school classes with a total of 187 children (89 girls and 98 boys) aged 12-13 years were recruited from a medium sized city in Sweden. To prevent confounding variables like socioeconomic factors, large schools with many parallel classes in each age group were chosen, and the same school was represented in all conditions. This age range was chosen because it is the oldest group of children in Sweden who mainly use one particular "home classroom." One participant was excluded prior to the analysis due to not following the instructions. Each class was paid 1500 SEK to participate and was randomly assigned to three independent groups: road traffic noise (N = 50), irrelevant speech (N = 66), and silence (N = 70).

Performance tests

Reading test. This test was used to measure reading speed and comprehension. It was very similar to the one used in Johansson. [12] The test consisted of a four-page story. With regular intervals there was a critical choice point. At these points, three words were presented. Each word was grammatically correct in the phrase in which they occurred, but two of them were wrong in the context. The task was to underline the word that was correct in the context. Reading speed was measured as the amount of underlined words. Reading comprehension was measured as the amount of correct responses. Maximum score was 40 points and the time limit for the task was 15 min. The following is an excerpt from the text:

I observed him (carefully/uninterestingly/barely) from my hiding place. He had the face of an Eskimo, but I had seen such people earlier here at the West Coast. They often spoke English with an accent and were difficult to understand.

Basic mathematics

This test consisted of arithmetical and geometrical problems. The arithmetical tasks were division (three problems) and multiplication (three problems). The geometrical problems were naming points in a coordinate system (two problems), understanding of the relationship between fractional expressions and areas of figures (four problems), understanding of the relationship between distance and numerical expressions (two problems), and measuring of distances (two problems). All participants had pencil, eraser, and ruler to help during the test. The maximum score on the task was 16. The time limit was 15 min.

Mathematical reasoning test

The reasoning test consisted of problems expressed in a word form and had a numerical solution. The maximum score was 7 points and the time limit was 15 min. The following problem was included in the test:

If Mary was three years younger than she is now, she would be exactly half the age she will be in three years from now. How old is Mary now?

Word comprehension test

This test was used to measure children's verbal ability. The results from this test were used as a covariate in the statistical analyses to control for participants' general cognitive ability, to double check the randomization and to reduce error variance. The word comprehension test contained 10 target words. Each target word was accompanied with five multiple-choice words; one was synonymous with the target word. The children were instructed to mark the synonymous word. The maximum score was 10 points and there was no time limit, but all pupils finished within 6 min.


In the noise conditions, digital recordings of road traffic noise or irrelevant speech were played back through loudspeakers at the front of the classroom. The equivalent sound level (Leq) in the noise conditions was set to 66 dBA 2 m in front of the loudspeakers. The road traffic noise recording was made up of a background of continuous road traffic noise (~62 dBA) with superimposed segments of trucks passing by. The peaks in the superimposed segments were at 78 dBA, occurred on average once per minute, and were of different durations. The irrelevant speech recording consisted of background babble (~62 dBA). Segments from a conversation between teenagers, only one person talking at the time, were superimposed on the babble background to match the dBA-against-time history of the road traffic noise. The background babble had no discernable meaning, while the conversation did. The dominant frequency range for the road traffic noise (100-300 Hz) was lower than that for the irrelevant speech (500-1500 Hz).


The experiment was executed in the home classrooms. All children sat at their ordinary desks and worked on the tasks individually. All experimental sessions were held before lunch time and lasted for approximately 1 hour, respectively. At the outset, the children were informed that the study was about noise. They were told that they would be given separate instructions and time limits ahead of each task. All children began performing the word comprehension test in silence. In order to compensate for fatigue effects, the sequences of the other three tasks were counterbalanced by a Latin-square design.

  Results Top

All statistical analyses were performed in SPSS 16.0 for Windows. The correlation between performance in the word comprehension test and in the other tasks was significant in each case [Table 1]. The word comprehension score in the three groups did not differ significantly [Table 2]. The statistical analyses yielded similar results with and without using the word comprehension test as a covariate. Therefore, only analyses without the covariate are reported here.

Reading test

Reading speed within each group is displayed in [Table 2]. A one-way analysis of variance found a significant effect of noise and post hoc Bonferroni adjusted t-tests revealed that Reading speed was slower in the road traffic noise condition than in the silent condition, P < 0.01, and in the irrelevant speech condition, P < 0.01. The difference between silence and irrelevant speech was non-significant. Thus, reading speed was slowed down by road traffic noise, but not by irrelevant speech.

To test whether noise disrupts reading comprehension, we calculated the proportion of the answered items that were correct. These data are summarized in [Table 2]. An analysis of variance with the proportion of correct answers on the reading comprehension test as dependent variable found no significant effect on noise. Hence, neither road traffic noise nor irrelevant speech disrupted reading comprehension.

Basic mathematics

The mean scores on the basic mathematical problems are shown in [Table 2]. A one-way analysis of variance with basic mathematics as dependent variable revealed an effect of noise, and post hoc Bonferroni adjusted t-tests revealed that road traffic noise reduced performance relative to silence, P < 0.05. No other comparison was significant.

Mathematical reasoning

As shown in [Table 2], the differences between conditions in the mean score on the mathematical reasoning test under noise and quiet conditions were very small and nonsignificant.

  Discussion Top

This experiment tested the effects of road traffic noise and irrelevant speech on children's reading comprehension, reading speed, basic mathematics, and mathematical reasoning. Reading comprehension was not impaired by any of the noise sources. These results are in line with Johansson [12] who found no effect of octave band noise on a similar reading comprehension task. A relatively large body of research has shown that people's performance on tasks involving semantic processing, such as reading comprehension, is particularly impaired by the semantic meaning in speech sounds. [13],[14],[18],[25] The absence of speech effects in the present investigation is therefore probably a result of the relative absence of semantic meaning in the speech sound. However, we found children's reading speed to be slowed down by road traffic noise. Given that comprehension was not impaired by noise, but speed was, this finding suggests that children either had to spend more time on backtracking through the text while reading in road traffic noise because their encoding was disturbed or they had to spend more time on encoding as they worked through the text without backtracking. Further experiments are needed to disentangle these two alternative interpretations.

Reading comprehension and reading speed are of course linked together, at least when it comes to a reading test with time limit. Measurements of reading speed are not reported in the RANCH study. In the Munich study, they measured reading speed, but they found no significant effect of noise exposure. However, it would be fruitful to develop a reading comprehension test that blocks the possibility to backtrack in the text; such a test would provide the opportunity to separate reading comprehension from reading speed.

Children's performance in the basic mathematics task was hampered by road traffic noise, but not by irrelevant speech. Hence, in contrast with the results reported by Kassinove, [21] the results reported here show that noise can have an effect on basic mathematics. However, there was no effect of noise on the mathematical reasoning task. These results were somewhat surprising since mathematical reasoning involves complex processing, and complex span tasks seems especially sensitive to noise effects.

Why is road traffic noise particularly disruptive to cognitive performance? To answer this question, it may be useful to address a study by Shield and Dockrell. They found that the noise parameter with the highest and most significant correlations with test scores was L A max , implying that noise of individual events may be the most important in affecting children's performance. This could be true for the present study too, since the road traffic noise we used had superimposed segments of trucks passing by. The peaks in the superimposed segments occurred on average once per minute. Thus, one possible interpretation could be that loud short events are the main problem with road traffic noise. Shield and Dockrell [20] suggested that the setting and the internal layout of a school should be such that classrooms are not exposed to high levels of noise from external sources such as road traffic. Another way to reduce the school children's noise exposure from road traffic is to plan heavy traffic to late hours, after school time.

There is a lot of good research regarding chronic noise exposure and cognitive performance, health, disturbance etc. The RANCH project and the Munich study have given us a wide knowledge about the relationship between chronic noise exposure and school performance. But, experimental studies in the field of noise and cognitive school performance show diverse results. Thus, further experimental studies are required to determine how and why different noises affect different cognitive abilities. An extension would be to look into how different levels of each noise source affects different abilities, and a credible dose-response curve could be established, which would be essential source of knowledge when new standards are to be established.

  Acknowledgement Top

Authors would like to thank Mεrten Eriksson for the suggestion of using a word comprehension test as a covariate.

  References Top

1.ANSI S12.60-2002. Acoustical performance criteria, design requirements, and guidelines for schools. American National Standards Institute; 2002.  Back to cited text no. 1      
2.Hygge S, Evans GW, Bullinger M. A prospective study of some effects of aircraft noise on cognitive performance in school children. Psychol Sci 2002;13:469-74.  Back to cited text no. 2      
3.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.  Back to cited text no. 3      
4.Stansfeld SA, Berglund B, Clark C, Lopez-Barrio I, Fischer P, Ohrstrφm E, et al. Aircraft and road traffic noise and children's cognition and health: a crossnational study. Lancet 2005;365:1942-9.  Back to cited text no. 4      
5.Clark C, Stansfeld SA. The effect of transportation noise on health and cognitive development: a review of recent evidence. Int J Comp Psychol 2007;20:145-58.  Back to cited text no. 5      
6.Haines MM, Stansfeld SA, Head J, Job RF. Multilevel modeling of aircraft noise on performance tests in schools around Heathrow Airport London. J Epidemiol Commun Health 2002;56:139-44.  Back to cited text no. 6      
7.Evans GW, Lepore SJ. Nonauditory effects of noise on children: A critical review. Child Environ 1993;10:31-51.  Back to cited text no. 7      
8.Shield BM, Dockrell JE. The effects of noise on children at school: A review. Journal of Building Acoustics, 2003;102:97-116.  Back to cited text no. 8      
9.Beaman CP. Auditory distraction from low-intensity noise: A review of the consequences for learning and workplace environments. Appl Cogn Psychol 2005;19:1041-64.  Back to cited text no. 9      
10.Hygge S, Boman E, Enmarker I. The effects of road traffic noise and meaningful irrelevant speech on different memory systems. Scand J Psychol 2003;44:13-21.   Back to cited text no. 10      
11.Boman E. The effects of noise and gender on children's episodic and semantic memory. Scand J Psychol 2004;45:407-16.  Back to cited text no. 11      
12.Johansson CR. Effects of low intensity, continuous and intermittent noise on mental performance and writing pressure of children with different intelligence and personality characteristics. Ergonomics 1983;26:275-88.  Back to cited text no. 12      
13.Martin RC, Wogalter MS, Forlano JG. Reading comprehension in the presence of unattended speech and music. J Memory Lang 1988;27:382-98.  Back to cited text no. 13      
14.Oswald CJ, Tremblay S, Jones DM. Disruption of comprehension by the meaning of irrelevant sound. Memory 2000;8:345-50.  Back to cited text no. 14      
15.Sφrqvist P, Halin N, Hygge S. Individual differences in susceptibility to the effects of speech on reading comprehension. Appl Cogn Psychol Published online in Wiley Inter Science 2009DOI: 10.1002/acp.1543  Back to cited text no. 15      
16.Jones DM, Miles C, Page J. Disruption of proofreading by irrelevant speech: Effects of attention, arousal or memory? Appl Cogn Psychol 1990;4:89-108.  Back to cited text no. 16      
17.Venetjoki N, Kaarlela-Tuomaala A, Keskinen E, Hongisto V. The effect of speech and speech intelligibility on task performance. Ergonomics 2006;49:1068-91.  Back to cited text no. 17      
18.Marsh JE, Hughes RW, Jones DM. Auditory distraction in semantic memory: A process-based approach. J Memory Lang 2008;58:682-700.  Back to cited text no. 18      
19.Marsh JE, Hughes RW, Jones DM. Interference by process, not content, determines semantic auditory distraction. Cognition 2009;110:23-38.  Back to cited text no. 19      
20.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.  Back to cited text no. 20      
21.Kassinove H. Effects of meaningful auditory stimulation on children's scholastic performance. J Educ Psychol 1972;63:526-30.  Back to cited text no. 21      
22.Zentall SS, Shaw JH. Effects of classroom noise on performance and activity of second-grade hyperactive and control children. J Educ Psychol 1980;72:830-40.  Back to cited text no. 22      
23.Dockrell JE, Shield BM. Acoustic barriers in classrooms: The impact of noise on performance in the classroom. Br Educ Res J 2006;32:509-25.  Back to cited text no. 23      
24.Hygge S. Classroom experiments on the effects of different noise sources and sound levels on long-term recall and recognition in children. Appl Cogn Psychol 2003;17:895-914.  Back to cited text no. 24      
25.Bell R, Buchner A, Mund I. Age-related differences in irrelevant-speech effects. Psychol Aging 2008;23:377-91.  Back to cited text no. 25      

Correspondence Address:
Robert Ljung
Centre for Built Environment, University of Gävle, SE 801 76 Gävle
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/1463-1741.56212

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