Given the limited studies conducted within the African continent, the purpose of this study was to investigate the impact of chronic aircraft noise exposure and the moderating effect of home language on the learners' reading comprehension. The sample comprised 437 (52%) senior primary learners exposed to high levels of aircraft noise (Experimental group) and 337 (48%) learners residing in a quieter area (Control group). Of these, 151 learners in the Experimental group spoke English as a first language (EFL) and 162 spoke English as a second language (ESL). In the Control group, the numbers were similarly divided (EFL n = 191; ESL n = 156). A univariate General Linear Model was used to investigate the effects of aircraft noise exposure and language on reading comprehension, while observing for the possible impact of intellectual ability, gender, and socioeconomic status on the results. A significant difference was observed between ESL and EFL learners in favor of the latter (F 1,419 = 21.95, P =.000). In addition a substantial and significant interaction effect was found between the experimental and control groups for the two language groups. For the EFL speakers there was a strong reduction in reading comprehension in the aircraft noise group. By contrast this difference was not significant for the ESL speakers. Implications of the findings and suggestions for further research are made in the article.
Keywords: Aircraft noise, home language, reading comprehension, South Africa
|How to cite this article:|
Seabi J, Cockcroft K, Goldschagg P, Greyling M. The impact of aircraft noise exposure on South African children's reading comprehension: The moderating effect of home language. Noise Health 2012;14:244-52
|How to cite this URL:|
Seabi J, Cockcroft K, Goldschagg P, Greyling M. The impact of aircraft noise exposure on South African children's reading comprehension: The moderating effect of home language. Noise Health [serial online] 2012 [cited 2020 Jun 1];14:244-52. Available from: http://www.noiseandhealth.org/text.asp?2012/14/60/244/102963
| Introduction|| |
A major challenge facing the South African education system is to address the needs of all learners, regardless of their geographical and linguistic backgrounds. Education is one of South Africa's most significant areas of concern. An Annual National Assessment conducted recently indicates that 65% of Grade 3's and 72% of Grade 6's are not at the grade appropriate language level.  Given such statistics, it is evident that the country's schooling system performs well below its potential, and that improving the basic education outcome is a prerequisite for the national long-term development goal. A part of improving the educational system lies in identifying the areas of concern that may impede the optimal transference of knowledge and learning. This includes factors that are often overlooked and thought to only affect a few, such as environmental noise.
It has been established that aircraft produce a considerable amount of noise.  Given this, it seems logical for airports to be situated reasonably far from areas such as residences and schools, where noise can be a significant source of distraction and annoyance. , However, this is not the case in South Africa, as there are several airports situated close to learning environments. Schools are learning environments that should stimulate cognitive development, facilitate transfer of knowledge, and enable children to learn about the society they live in.  Having loud noise sources (such as airports) close to schools may compromise the learning process. Although there is research from Western countries regarding exposure to aircraft noise and its impact on reading comprehension, , to the best of the authors' knowledge, there is no research in this area within developing countries, such as South Africa.
The impact of unwanted noise on learning is confounded by the fact that South Africa has eleven official languages. This multilingual characteristic presents interesting dynamics to the investigation of reading comprehension and aircraft noise. Learning in South Africa is predominantly facilitated in English followed by Afrikaans, although statistics indicate that a majority of the population (74%) speak an indigenous (African) language as their first language. Therefore, for many learners, English is their second and sometimes even their third language, which they may not be proficient in.  Thus, English second language (ESL) learners may be at a double disadvantage, having to read and comprehend in their second language and simultaneously having to contend with background air traffic noise.
Sources of noise in the classroom
In South Africa, learning is predominantly facilitated by a teacher giving instructions orally, while learners listen and absorb the information. Classrooms, therefore, need to support communicative behavior to facilitate learning. Noise in the classroom consists of a combination of external noise, which permeates into the building, together with internally generated noise.  Internal noise mainly consists of noise generated by the learners themselves, as they participate in classroom activities and converse among themselves. External noise, on the other hand, as highlighted, includes noise from transportation sources, such as road traffic, aircraft noise (for some schools), and to a lesser degree, railway noise. A survey conducted in London indicates that sources of external environmental noise include cars, which account for 86%, aircraft 54%, lorries 35%, and buses 24% of the noise, respectively.  Research in South Africa indicates similar trends of environmental noise experienced by learners in the classroom.  Children are thus exposed to noise from several sources when they are learning. Although it is acknowledged that internal noise can interfere with the learning process, external noise is envisaged to pose an even great er distraction to learning activities. The logic being that, unlike internal noise, aircraft noise, for example, is louder and intermittent, and consequently educators and learners have less (if any) control over such a noise.  Thus, learners situated near high levels of environmental noise may be at a higher risk of academic delays than learners who are not exposed to noise levels that infringe on the optimal acoustic levels in a classroom. Academic delays experienced by these learners may be in the form of impaired reading ability and comprehension, which the current study tries to investigate.
The ability to read is one of the leading factors for the learners' successful transitioning to higher grades of learning; with different levels requiring a higher order of thinking and understanding of texts. It is widely recognized that language and reading proficiency are pivotal to education attainment and success, primarily because education is still largely a language-based activity.  Effective reading requires the reader to actively engage with the text to extract the meaning from it, as the reader attempts to 'comprehend the thoughts and feelings of another mind via the text'. 
A reader's understanding of a text can be limited by various barriers, language being the most obvious one.  If a reader does not possess a good command of the language that the text is in, there is a high chance of a limited understanding of that text;  thus, introducing a language bias. Issues around language bias are pertinent in multilingual countries such as South Africa. Sternberg's  linguistic relativity hypothesis is of interest, given the predicament of language bias. In the context of this hypothesis, a learner's understanding of classroom assessment is potentially a function of language. Essentially the hypothesis suggests that a learner's comprehension of a text is dependent on and limited to the learner's level of competency of the language in which the text is written. The hypothesis further proposes that people develop certain cognitive styles and interpretations based on the language they communicate in. A criticism of this hypothesis is that it underestimates people's capabilities to comprehend texts that are not in their dominant language. What the linguistic hypothesis argument does highlight is that language can play a role in creating discrepancies in learning that may place ESL speakers at a reading disadvantage compared to EFL speakers, if they are all being educated in English. 
Cummin's  theory, further premises that there are two facets to language proficiency, namely, Basic Interpersonal Communication Skills (BICS) and Cognitive Academic Language Proficiency (CALP). BICS are primary skills pertaining to listening and speaking, such as, being able to hold a fluent conversation in English on a day-to-day basis. CALP on the other hand is the ability to cope with the academic demands of a language, such as, the comprehension of texts. The theory suggests that even if one can converse fluently in English, for example, this does not automatically translate to the academic skill of comprehending a text in English, in school.  Application of this theory in a South African context, where the medium of teaching is predominantly English, raises questions of whether learners from different linguistic backgrounds have acquired both BICS and CALP. A South African study found that ESL speakers performed significantly lower than EFL speakers, on an assessment that measures reading ability.  This suggests that ESL learners may not have acquired the levels of CALP needed to effectively comprehend a text. The linguistic character of South Africa is one where many South African learners are likely to have acquired BICS, but their CALP may not be adequately developed and this puts them at a greater risk of underachieving in an English medium school in comparison with their EFL counterparts.
Aircraft noise in the context of reading comprehension
The impact of aircraft noise on cognitive tasks, such as reading comprehension, has been researched over the past 30 years. Given that reading comprehension involves higher cognitive processes such as attention and memory, and these processes appear to be sensitive to exposure to chronic noise,  it is logical to assume that deficits in reading performance may be found as a result of noise exposure. Indeed, research has found reading comprehension to be more sensitive to noise than other cognitive tasks,  and this is possibly because of its extensive dependence on memory. Hockey  found that participants exposed to loud noise conditions had better recall of names from a passage, but poorer overall comprehension, than those in quieter environments. A significant drop in children's school performance, especially in learning to read, was found when the background noise level interfered with speech.  Evans and Maxwell  also found deficits in language skills among six-and eight-year old children exposed to chronic aircraft noise. Shield and Dockrell  found a negative association between children exposed to chronic aircraft noise and reading comprehension. Quite recently, impairments in reading comprehension performance were demonstrated among children aged nine to ten years, exposed to noise at three airports at Heathrow, Munich and Madrid in Europe.  In another study, exposure to chronic aircraft noise was associated with a six-month delay in the reading ability of eight-to eleven- year- old children and the differences remained even after adjusting the analyses for age, language spoken, and level of economic standing.  This was particularly important because it suggested that language might not necessarily facilitate differences in reading comprehension skills. However, it was imperative to infer results obtained from any study with caution. It could be that such results in the Heathrow study might have been context-specific. The study was conducted in London, where learners from different cultural backgrounds were arguably more similarly exposed to English, in comparison to South Africa, where English may be an official language, but is not spoken equally by all people.
Although these studies ,,,, reveal a consistent association between reading comprehension and exposure to chronic noise, no significant effect of noise on reading comprehension was found. , However, when Hygge et al.  conducted a separate analyses of the 15 most difficult items in the reading comprehension test, a significant difference between the two groups was demonstrated, and this remained even after adjustment for age, socioeconomic deprivation, and home language, [F (1, 417) = 4.75, P = 0.032]. This finding suggests that chronic exposure to aircraft noise impairs learners' performance only on difficult items of the reading comprehension test. Simple cognitive tasks that require less attention for processing appear not to be affected by noise. Investigating whether similar findings would be observed in a multilingual context, such as in South Africa, is useful, as this may indicate whether it is significantly more difficult for ESL learners to comprehend texts that demand greater CALP skills.
The present article focuses on a cross-sectional cohort, and examines whether effects of exposure to aircraft noise can be found on reading comprehension, and if so, whether the language spoken at home mediates the effects.
The general aim of the study was to examine the effects of exposure to chronic environmental noise, by comparing the reading comprehension performance of learners exposed to aircraft noise with those not exposed to aircraft noise. As language is inextricably tied to reading and comprehension, the further aim was to examine the influence of language on reading comprehension. In order to gain insight into the possible factors that affect reading comprehension, the following questions guided the study:
- Does exposure to chronic aircraft noise impact negatively on primary school learners' reading comprehension?
- Is there a significant difference between English First Language (EFL) learners' and English Second language (ESL) learners' reading comprehension abilities?
- Does language spoken at home play a moderating role in the impact of aircraft noise on reading comprehension?
| Methods|| |
Context of the study
The current study was conducted under the auspices of a longitudinal South African-based study namely, the Road and Aircraft Noise Exposure on Children's Cognition and Health (RANCH-SA). RANCH-SA which was based on the original RANCH project investigated the impact of environmental noise, specifically aircraft noise, on primary school learners' memory, attention, and reading comprehension abilities in the province of KwaZulu Natal. Durban International Airport (prior to relocation to the new King Shaka International Airport site), was selected as a case study. Two schools exposed to a high level of aircraft noise (experimental group) were selected as the study population for the aircraft noise exposure area. The control group comprised of three schools in locations not exposed to aircraft noise, but that matched the sociodemographic characteristics (such as language spoken at home, parental education, and occupation) of the noise-exposed areas. Schools located outside the flight paths were selected by visual inspection of maps of the areas surrounding Durban International Airport.
The sample comprised of 834 participants from five schools, located either in a high aircraft noise urban area (16 hours outdoor Leq > 69 dBA) around the Durban International Airport or in a relatively quieter area (16 hours outdoor Leq < 40 dBA). The participants were all from similar sociodemographic backgrounds. The schools were selected on the basis of their proximity to and distance from the airport. The two schools situated under the aircraft flight path formed the experimental group and consisted of 437 (52%) participants, while the three schools situated far from the airport formed the control group and comprised of 337 (48%) participants. The participants' ages ranged from 9 to 14 years with a mean age of 11.9 years. There were 322 (39%) males and 331 (40%) females, while 181(21%) participants did not respond to the gender category. Out of 834 participants, 410 (49%) spoke English as a first language, while 374 (45%) spoke English as a second language (they spoke IsiZulu, IsiXhosa or Sesotho as a first language). The primary language of 50 (6%) of the participants was unknown, as they did not complete this item on the biographical questionnaire. Three hundred and seventy-one participants (44%) reported that they received free meals at school, while 338 learners (40%) did not receive meals, and 125 (16%) participants indicated that they were unsure about this question. This study utilized a non-probability purposive sampling technique. Criteria for participating in the study were a minimum of two years of residence in the area of study, normal hearing (as perceived by parents and teachers), and being in Grade 5 or 6 at the time of the study. Those with known learning difficulties, auditory processing disorders and / or attentional problems were allowed to participate, but excluded from the analyses.
Written permission was obtained from the education authorities and from the parents / guardians to allow their children to participate in the study. Informed assent from the learners was also obtained. The cognitive performance tests were group-administered in the classrooms, between 8 and 10 in the morning. They were informed of the limits of confidentiality, as well as the voluntary nature of their participation. RANCH-SA assessment administrators were trained in advance on the standard assessment protocol and how to administer the tests. All the assessments were conducted under normal air traffic (i.e. week day) movement conditions. On the day of testing, the assessment administrators introduced themselves according to the RANCH-SA script, which avoided the word 'noise,' so not to influence participants' perceptions of the study. The study was introduced as an environmental health study and noise questions were embedded in the environment and health sections. The Suffolk Reading Scale Level 2 (SRS2) was one of the assessments to be administered according to the RANCH-SA protocol. Each testing procedure began with practice items, to ensure that participants understood what was required in the assessment. The completed tests were placed in a coded envelop straight after the assessment was completed. The learners were offered crisps and fruit juice for participating in the study.
Although the RANCH-SA study utilized a number of instruments, in this article, the focus was on the Suffolk Reading Scale Level 2, biographical questionnaire, the noise measurement instrument, and intellectual ability.
Information pertaining to the participants' gender, age, race, and language was obtained from the biographical questionnaire completed by the participants and parents. The child questionnaire was administered in print form and completed before the assessment. The parent questionnaire was sent in advance to the participants' parents and collected from each learner on the day of the assessment.
Reading Comprehension was measured with the Suffolk Reading Scale Level 2 (SRS2).  This scale is used to measure the reading comprehension of children, ranging in age from 6 years 4 months to 13 years 11 months. It was standardized for children in the United Kingdom. The test comprised of 86 multiple choice sentence completion questions, each containing five potential answers. The SRS2 has a test- retest coefficient of 0.88 on the standardization sample.  Although the SRS2 had not been standardized in the South African context, it had a Cronbach's alpha of 0.93 when used with a sample of South African primary school learners. 
Intelligence was measured with the Figure Analogies subtest of the Quantitative battery for Cognitive Abilities Test.  The Figure Analogies test (also known as Matching Mate) presents figural analogies of the type 'A→B: C→?'. This test measures both inductive reasoning and visualization. It has a reported Kuder-Richardson reliability coefficient of 0.91.  This test was conducted on a sample of South African learners and found to be valid and reliable.  It was included in order to determine whether the comparison groups were equivalent in terms of intellectual ability.
The instrument used to measure noise was a SVAN 955 Type 1 sound level meter. A Rion NC74 acoustic calibrator was used to check the instrument calibration before and after the measurement was performed. Noise measurements were taken during the testing period (8 a.m. to 10 a.m.). The average sound level (LAeq) measured was 69, with a maximum of 95 dBA in the experimental group, and 40 LAeq, with a maximum of 54 dBA, in the control group.
The RANCH-SA study followed the following ethical procedures. For informed consent, an information letter was sent to the education authorities and to the parents of the potential participants. This letter outlined the information on the nature of the study and what participation would entail. This information letter also informed the parents of who would be able to access data; including the possibility of other researchers affiliated with the RANCH-SA accessing data. The right to withdraw at any point in the study, as well as how feedback from the study could be obtained were also highlighted. The potential participants were informed of the lack of direct benefit for participating in the study. A parent signing a consent form was considered as an informed consent; furthermore, the consent from the children themselves was also obtained. Only after consent from the educational authority and parents was obtained, were the children grafted into the study. Given the public nature of the assessments administered in a group setting, anonymity could not be ensured, but all the data were confidential.
| Results|| |
Of note, out of a total of 834, 141 (17%) participants did not complete the reading comprehension assessment (due to lateness), therefore, in total only 693 (83%) of the scores were available for analysis. The reading comprehension mean for the South African sample was significantly lower (mean = 35.27; SD: 11.2) than that reported in a similar study (mean = 98.2) conducted in the UK.  The latter study also utilized the SRS2 and found a mean score of 99.29, after adjusting for ethnicity, main language, and age. The large difference in the mean highlighted the lower level of reading comprehension performance of the South African learners compared to UK learners.
[Table 1] below shows the mean scores on the SRS2 for both the control and experimental groups, as well as for EFL and ESL learners. As anticipated, learners who were not exposed to aircraft noise (control) showed a higher reading comprehension performance (M = 32.44, SD = 16.71) compared to the experimental group that was exposed to aircraft noise (M = 29.81, SD = 14.23).
|Table 1: Reading Comprehension scores of aircraft noise exposure and language groups|
Click here to view
A comparison between the language groups showed that the EFL learners performed significantly better (M = 36.19, SD = 14.91) in reading comprehension than their ESL counterparts (M = 28.60, SD = 13.51; t(658) = 6.83, P < 0.000), as presented in [Table 1]. This was anticipated, given that the SRS2 was an English assessment. Moreover, the mean score of the EFL learners was slightly above the study's overall average on the SRS2 (M = 35.27). This highlighted the fact that the overall reading comprehension performance of the EFL learners generally surpassed the reading comprehension performance of the study's sample as a whole. Meanwhile, the ESL learners not only performed significantly lower than their EFL counterparts, but as a group they performed below the sample's (overall) reading comprehension average.
The study is also interested in the potential interaction between aircraft noise and the home language on reading comprehension. The interaction means presented in [Table 2] show similar trends to the main effects, where the EFL learners not exposed to aircraft noise showed a superior reading comprehension performance (M = 40.9, SD = 14.06) to all the other groups in the study. As can be observed from the table, the largest difference in mean scores was between EFL learners in the control (M = 40.9) and EFL learners in the experimental group (M = 30.16). This suggests the presence of an interaction between aircraft noise and language, which is elaborated later on. For the ESL groups, on the other hand, whether they were exposed to chronic aircraft noise or not, their mean scores for reading comprehension were lower. This indicates that the effect of noise on the ESL learners' reading comprehension performance is generally negligible.
|Table 2: Interaction between Aircraft Noise and Language on Reading Comprehension|
Click here to view
A univariate general linear model was used to test the effect of aircraft noise and language on reading comprehension. In addition, the model controlled the possible impact of intellectual ability, gender, and socioeconomic status on the results. Intellectual ability was controlled as a covariate in the model, and although, no statistically significant differences were observed for either gender groups (F 1,419 = 2.47, P =.1168) or in the level of socioeconomic status (F 3,419 = 1.40, P =.2430), on reading comprehension (α = 0.05), they were also included to control the small extraneous effects and to improve the power of the test.
In addition, to null the hypothesis significance testing, the effect sizes were calculated. The effect sizes gave an indication of how much variance in reading comprehension is influenced by aircraft noise and / or language. Furthermore, the effect sizes enabled the researchers to establish the main effect that had the greatest influence on the reading comprehension performance of the different groups in the study. Although the SPSS software, used to analyze data in the study, supplied the partial Eta-squared effect sizes output, Cohen's d effect sizes were calculated instead. This was because Cohen's d was resistant to sample size influences, unlike the partial Eta-squared, which could be affected by a large sample size, such as that inherent in the current study.  Moreover, the partial Eta-squared values did not sum to one, making interpretation of the effect size problematic.
The effect of aircraft noise on reading comprehension
The first question sought to examine what, if any, impact aircraft noise had on reading comprehension. The results indicated statistically significant differences between the experimental and control groups on reading comprehension in favor of the control group (F 1,419 = 11.75, P = 0007). This implied that learners exposed to chronic aircraft noise had significantly lower scores for reading comprehension than learners not exposed to the same intensity of noise. However, a small effect size (d = 0.35) was determined. Thus, indicating that although exposure to aircraft noise negatively impacts on reading comprehension, the impact is minimal.
The effects of home language on reading comprehension
The second question asked whether there was a statistically significant difference between EFL learners and ESL learners on reading comprehension. It was postulated that EFL learners would perform significantly better than ESL learners, given that the test of reading comprehension, the SRS2, was an English-based assessment. As illustrated in [Table 3], a statistically significant difference was observed in favor of EFL learners (F 1,419 = 19.79, P <.0001). This suggested that the learners' primary language influenced their reading comprehension performance, particularly if the assessment was not in their home language. A moderate effect size (d = 0.46) for language on reading comprehension was determined. This was a larger effect than that of aircraft noise, and served to highlight the relatively larger influence language had on reading comprehension performance.
|Table 3: Summary of the main effects and interaction effects on reading comprehension|
Click here to view
The effects of aircraft noise and home language on reading comprehension
The present study also investigated whether aircraft noise and language interacted to influence the learners' performance on reading comprehension. As presented in [Table 3], the results showed a statistically significant interaction (F 1,419 = 19.46, P <.0001). The effect of this interaction was substantial (d = 0.87), implying a large, practical difference in the effect of aircraft noise on the performance of the two language groups.
The nature of the interaction between noise and the primary language spoken is illustrated in [Figure 1]. It is evident that the EFL speakers performed substantially better in the control condition (P < 0.0001, d = 0.78), while the ESL learners performed slightly worse in the control condition. This effect was, however, not statistically significant (P = 0.5366, d = 0.09).
|Figure 1: Aircraft noise and language interaction plots for reading comprehension|
Click here to view
| Discussion|| |
The effects of language on reading comprehension
It was postulated that the EFL learners would perform significantly better than their ESL peers on an English reading comprehension measure. This prediction was based on Stenberg's theory,  which suggested that low proficiency in the language of a text was likely to result in a limited understanding of that text. The results from the present study corroborated this prediction. These findings supported those found in a previous study, which revealed that ESL learners were at a greater disadvantage with regard to English literacy tasks, such as the SRS2. 
In addition, the ESL learners performed consistently lower than their EFL counterparts, irrespective of the environmental noise condition. Home language seemed to be a pertinent factor in determining successful reading comprehension for ESL learners. Such results were not unfathomable in light of the premises put forward by Cummins.  ESL learners had possibly acquired the basic communication (BICS) fluency in English, but may be lagging in terms of the academic proficiency (CALP) needed to effectively comprehend the reading task. English Second Language learners, unlike their EFL counterparts, were more likely to have the added effort of translating the text from English into their primary language and back to English again. Furthermore, they were more likely to have a lower vocabulary range, which placed them at a disadvantage for identifying words and extracting meaning from texts.  Moreover, learning in what could be considered a 'new or foreign language,' was argued to be frustrating and anxiety provoking, which could consequently affect the performance of the ESL learners.  All these factors could be considered as language barriers that interfered with the performance of ESL learners in English language-based tasks. It was possible that ESL learners would have achieved higher scores if the reading comprehension was assessed in a language they were more comfortable with and proficient in.
The issue of language bias in assessment and education is not new in South Africa and often results in what authors highlight as a misdiagnosis of language barriers and as learning disorders. , As highlighted by linguistic and social experts such as Alexander,  English remains the language of command in today's society, even in multilingual societies such as South Africa. As a result, this dominance of the English language extends to social institutions such as schools. The issue of language thus creates unequal playing fields in education in countries such as South Africa and possibly other countries that share similar linguistic characteristics.
The conundrum that South Africa faces is that despite the evidence of language biases in the learning areas, limited resources in the form of teachers and capital, to educate learners in all 11 official languages, restricts the transformative objectives of the Language in the Educational Policy.  Language remains a contentious topic in the country and findings from this and earlier studies highlight how it is clear that language plays a significant role in reading comprehension. However, how this problem can be rectified is not so apparent.
The effect of aircraft noise on reading comprehension
The findings of the study demonstrated a statistically significant difference between learners exposed to aircraft noise and those in a quieter area. However, this difference was only evident for the EFL speakers, who showed a substantial decrease in performance in the noisy environment. Thus, for EFL learners, these results corroborated with the earlier empirical studies, which demonstrated delayed reading ability for learners exposed to chronic aircraft noise. , These findings offered some evidence of the vulnerability of the reading comprehension of ESL children learning in a noisy environment. Unlike previous studies that also found significant noise effects on reading comprehension, the present study provided an indication of the extent to which noise impacts the reading comprehension performance. In this study substantial differences (d = 0.76) were found for the EFL group, under noisy conditions.
The largest significant difference in reading comprehension performance, when the effect of noise and language were analyzed concurrently, was observed in the EFL group. The EFL learners who were not exposed to aircraft noise had the highest performance on an English reading comprehension assessment. Such findings were expected, as there were higher chances of processing and understanding of a text or assessment when it was in one's primary language. , Furthermore, given that the EFL learners in the control group were not exposed to aircraft noise, they were in a more conducive environment, where they were less likely to be distracted by noise.
However, EFL learners situated within the vicinity of the airport, still performed significantly better than both ESL sample groups (control and experimental), but had significantly poorer reading comprehension performance in comparison to their EFL counterparts in a quieter area. These findings suggested that environmental stressors, such as aircraft noise, were able to compromise the performance of tasks such as reading, for learners who were not expected to struggle with such an assessment in their primary language. The physical environment for those already proficient in the language was crucial for optimal performance in classroom activities that involved the comprehension of texts. Given that the study controlled the gender, socioeconomic status, and intellectual ability, it was not unreasonable to suggest that aircraft noise hindered the reading comprehension performance of these learners. Research supported the notion that environmental noise could undermine the processes of learning and teaching. ,
On the other hand, the ESL group exposed to chronic aircraft noise showed little difference from the ESL group not exposed to noise in the reading comprehension assessment. These findings were not anticipated. One would expect that having to grapple with unfavorable conditions would pose as even more of a threat to an impaired reading comprehension performance in the context of processing 'another language'. Although there is some research that suggests that noise can improve concentration, as it raises one's attention,  the research focuses on noise in the test situation and will not account for the differences between the two groups. Findings of the current study do persuade rethinking of what is necessary for achievement in certain learning areas, for different learners. An alternative explanation for the different pattern of results for the language may be found in the history of racial segregation in South Africa, as race is strongly correlated with home language, and different race groups typically live in different socioeconomic areas. The ESL speakers may well live in significantly noisy environments due to sources of noise unrelated to aircraft. There is some evidence for this in the collected data, as participants have been asked about the level of noise experienced both at home and in the school environment. The noise experienced at school is greater in the group exposed to aircraft noise (F 1,723 = 49.23, P < 0.001, d = 0.52) and this effect is not significantly different for the two language groups. In contrast, there is a substantial difference in the impact of the experimental condition on the two language groups when the noise at home is considered. The noise experienced at home has been moderately larger for EFL respondents in the aircraft noise condition, when compared to the EFL speakers not exposed to aircraft noise (P < 0.001, d = 0.44). In contrast there has been little difference in the mean scores of the ESL groups under the two experimental conditions (P = 0.9796, d = 0.04). Interestingly, both ESL groups experience similar noise levels at home, which are not statistically significantly different from those of the aircraft-exposed noise group of the EFL speakers (d = 0.12 experimental, d = 0.07 control).
Limitations of the study and suggestions for future research
The results of the present study should be read in the context of the following limitations. Similar to most studies on aircraft noise, a cross-sectional analysis was conducted. A problem with such studies is that conclusions are correlational and causal inferences are highly unlikely.  Therefore, it cannot be said that chronic exposure to aircraft noise, for instance, causes impaired reading comprehension. True experiments that allow for casual inferences to be tested are not always practical and may compromise ecological validity, as they tend to be less naturalistic.  Moreover, while causal inferences cannot be drawn, information gained from correlational research is still able to contribute valuable knowledge to a field of study. 
Although language is central to learning aspects such as reading comprehension, it cannot be said that it is the sole factor that facilitates differences between English First language learners and English Second Language learners. Other variables such as learner motivation or access to learning resources within the school may be confounding with the language variable in the study and contributing to the differences observed. Aspects such as learner motivation, or an educators teaching style are not controlled in the study and are beyond the scope of this study, but they are important areas for future research.
| Conclusion|| |
The study examined the impact of aircraft noise and language on the cognitive ability of reading comprehension in a sample of learners in Durban. The findings of the study provide some insight into the possible effects that environmental noise and sociocultural factors such as language pose on the cognitive ability of reading comprehension. They suggest that marginalization can take on various dimensions, socially, culturally, and even geographically. It is not being suggested that because one is exposed to chronic aircraft noise, or one is speaking English as a second or third language, it equates to lower levels of reading comprehension skills. Rather the findings indicate that those who are exposed to chronic aircraft noise or who are not primary English learners are more likely to have difficulties and exhibit lower reading comprehension skills than those who are not in a similar position. Findings in the study further reiterate the notion that learners cannot be fitted into one mold; different learners have varying priority needs for optimal educational development. For EFL groups, noisy environments have the greatest negative impact on reading comprehension performance, while for ESL groups, home language is a more likely influential predictor of reading comprehension performance.
The ability to read and comprehend a text infiltrates into most if not all areas of learning and is thus crucial for progression in the educational sphere in today's world. Thus, exposure to environmental aircraft noise and issues of language are not the only factors that affect the important skill of reading comprehension. The significance of examining these factors should be for remedying the identified areas that affect education. The importance of fostering the most favorable educational experience is patent.
"Education is the great engine of personal development. It is through education that the daughter of a peasant can become a doctor, that a son of a mineworker can become the head of the mine, that a child of farm workers can become the president of a great nation"(Nelson Mandela).
Any effort that enhances the educational experience of all learners in a country such as South Africa is indispensable.
| Acknowledgments|| |
The researchers would like to thank the learners who participated in the study. Without their generous participation this research would not have been possible. This material is based upon work supported financially by the National Research Foundation (NRF). Any opinions, findings and conclusions or recommendations expressed in this material are those of the authors and therefore the NRF does not accept any liability in regard thereto. This publication was also made possible (in part) by a grant from the Carnegie Corporation of New York. The statements made and views expressed are, however, solely the responsibility of the authors. Lastly, the first author is grateful of the SPARC fund and Writing Retreat facilitated by Prof. Van Zyl and Prof. Worby.
| References|| |
|1.||Department of Basic Education. Macro-Indicator Trends in the Schooling System. 2011. Pretoria: DBE. |
|2.||Stansfeld SA, Berglund B, Clark C, Lopez-Barriro I, Fischer P, Ohrstrom E, et al. Aircraft noise and road traffic noise and children's cognition and health: a cross-sectional study. Lancet 2005;365:1942-9. |
|3.||Goldschagg, P. Airport noise in South Africa-Prediction models and their effect on land use planning. 2007. Unpublished Doctoral Dissertation, University of Stellenbosch. |
|4.||Rivlin LG, Weinstein CS. Educational issues school settings and Environmental Psychology. Environ Psychol 1984;4:347-64. |
|5.||Clark C, Stansfeld SA. The effect of aircraft noise and road traffic noise on children's reading. Lit Today 2005;44,9:24-25. |
|6.||Evans GW, Maxwell L. Chronic noise exposure and reading deficits: The mediating effects of language acquisition. Environ Behav 1997;29:638-56. |
|7.||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;31:265-27. |
|8.||Pretorius E, Naudé H. A culture transition: Poor reading and writing ability among children in South African townships. Early Child Dev Care 2002;172:439-49. |
|9.||Shield BM, Dockrell JE. The effects of noise on children and schools: A review. Build Acoust 2003;10:97-106. |
|10.||Shield BM, Dockrell JE. The Prevalence of Injuries among Pianists in Music Schools in Ireland. Med Probl Perform Art 2000;15:155-60. |
|11.||Seabi J, Goldschagg P, Cockcroft K. Does aircraft noise impair learners' reading comprehension, attention and working memory? A pilot study. J Psychol Afr 2010;20:109-12. |
|12.||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. |
|13.||Webb V. Language planning and politics in South Africa. Int J Sociol Lang 1996;118:139-62. |
|14.||Pumfrey PD. Measuring reading abilities: Concepts, sources and applications. Manchester: Department of Education; 1977. |
|15.||Orasanu J. Reading comprehension: From research to practice. New Jersey: Laurence Erlbaum Associates; 1986. |
|16.||Sternberg RJ. Successful intelligence: How practical and creative intelligence determine success in life. New York: Simon and Schuster; 1996. |
|17.||Ramaahlo M. The Application of the Suffolk Reading Scale (2) on South African Learners. Unpublished M.A. Dissertation: University of the Witwatersrand; 2010. |
|18.||Cummins J. Language development and academic learning. In Malavé LM, Duquette G, editors. Language, culture and cognition: A collection of studies in first and second language acquisition. Clevedon: Multilingual Matters; 1991. p. 161-75. |
|19.||de Klerk V. Language Issues in our schools: Whose voice counts? Part 1: The parents speak, Perspect Educ 2002;201:1-14. |
|20.||Ireland-Lathy HL. An assessment of reading in First Language and Second Language learners who experience barriers to learning. Unpublished Masters Dissertation. University of the Witwatersrand; 2006. |
|21.||Goldman SR, Bisanz GL. Toward a functional analysis of scientific genres: Implications for understanding and learning processes In: Otero J, León JA, Graesser AC, editors. The psychology of science text comprehension. NJ: Erlbaum, Mahwah; 2002. p. 19-50. |
|22.||Jones D. Recent advances in the study of human performance in noise. Environ Int 1990;16:447-58. |
|23.||Hockey R. Stress and the cognitive components of skilled performance. In: Hamilton V, Warburton DM, editors. Human Stress and Cognition. New York, NY: Wiley; 1979. p. 141-77. |
|24.||Hetu R, Truchon-Gagnon C, Bilodeau SA. Problems of noise in school settings. J Speech Lang Pathol Audiol 1990;14:31-9. |
|25.||Shield BM, Dockrell JE. The effects of noise on the attainments and cognitive performance of primary school children. Department of Health, United Kingdom, 2002. |
|26.||Stansfeld SA, Berglund B, Clark C, Lopez-Barrio I, Fischer P, Ohstrom W, et al. Aircraft and road traffic noise and children's cognition and health: exposure-effect relationships. Lancet 2005;365:1942-9. |
|27.||Hygge S, Evans GW, Bullinger M. A prospective study of some effects of aircraft noise on cognitive performance in school children. Psychol Sci 2002;13:46-974. |
|28.||Hagley F. Suffolk Reading Scale. Windsor: NFER-NELSON; 1987. |
|29.||Hagley F. Suffolk Reading Scale II: Teacher's Guide. London: GL Assessment; 2002. |
|30.||Lohman DF, Hagen EP. Cognitive Abilities Test (Form 6): Research handbook. Itasca, IL: Riverside Publishing; 2002. |
|31.||Haines MM, Stansfeld SA, Brenthall J, Head J, Berry M, Jiggins S, et al. The West London Schools Study: The effects of chronic aircraft noise exposure on child health. Psychol Med 2001;31:1385-96. |
|32.||Rosenthal R, Rosnow RL. Essentials of behavioral research: Methods and data analysis. 2 nd ed. New York: McGraw Hill; 1996. |
|33.||Cornoldi C, Oakhill J. Reading Comprehension Difficulties: Processing and Intervention, Lawrence Erlbaum: New Jersey; 1996. |
|34.||Kamwendo GH. No easy walk to linguistic freedom: A critique of language planning during South Africa's first decade of democracy. Nordic J Afr Stud 2006;15:53-70. |
|35.||Foxcroft C, Roodt G. An introduction to psychological assessment in the South African context. Oxford: Oxford University Press; 2001. |
|36.||Alexander N. Mother tongue-based bilingual education in South Africa: The dynamics of implementation. Cape Town: Salty Print; 2005. |
|37.||Department of Education. Language in Education Policy. Government Gazette, 17997; (383). Pretoria: Government Printer; 1997. |
|38.||Cain K, Oakhill J. Assessment matters: Issues in the measurement of reading comprehension Br J Educ Psychol 2006;76:697-708. |
|39.||Berglund B, Lindvall T, Schwela DH, editors. Guidelines for Community Noise. London: World Health Organization; 1999. |
|40.||Hygge S. Classroom experiments on the effects of difference noise sources and sound levels on long-term recall and recognition in children. Appl Cognit Psychol 2003;17:895-914. |
|41.||Berglund B. Health effects of community noise, In: Newman M, editor. Proceedings of the 15 th International Congress of Acoustics, Trondheim: Acoustical Society of Norway; 1995. p. 11-5. |
|42.||Whitley BE. Principals of research in behavioral science. New York: McGraw Hill; 2002. |
|43.||Bryman A. Quantity and Quality in Social Research. London: Routledge; 1993. |
Private Bag 3, Department of Psychology, School of Human and Community Development, University of the Witwatersrand, 2050
Source of Support: National Research Foundation (NRF) and Carnegie Corporation of New York, Conflict of Interest: None
[Table 1], [Table 2], [Table 3]