Ruído externo às salas de aula e sua relação com o desempenho cognitivo, rendimento escolar e indicadores de saúde de adolescentes: estudo de caso

Abstract

The school must provide a suitable environment so that students can perform their activities. Studies have shown that classrooms do not have satisfactory acoustic conditions, although noise, produced inside and outside classrooms, may impair cognitive performance and, therefore, the teaching-learning process. There are references that classroom noise can affect school health by raising blood pressure, heart rate, and some hormones, such as cortisol, related to stress. In Brazil, studies of this nature are incipient, even though it has already been shown that public schools in different regions of the country do not present adequate acoustic environment. The present study evaluates the relationship between noise outside classrooms with school performance, cognitive performance, and adolescents health indicators. This is a comparative observational study carried out in two state schools of basic education, located in the urban zone of the city of Santa Cruz do Sul, in Rio Grande do Sul. The school denominated A is located in a typical residential neighborhood, without urban traffic in its surroundings. School B is located in front of a military unit, which acts with armored vehicles, in a street with intense traffic of vehicles. The results show that the average noise outside the classrooms (LAeq 67 dB) in school B is higher when compared to school A, which reached acceptable levels (LAeq 46 dB), considering values cited in the Brazilian normalization. Both schools do not present satisfactory acoustic environment inside the classrooms, having a high Reverberation Time and achieving a "reasonable" classification in all rooms when related to the Speech Transmission Index and the Loss of Articulation of the Consonants. The students´ perception regarding to acoustic conditions is more negative in school B, it is noisier, and also, the results on the evaluation of cognitive and school performance are more unsatisfactory. Among health indicators, cortisol levels, which should naturally decrease in the morning, show that students in school A decrease approximately twice as much in the morning compared to students in school B, suggesting that external stressors may be influencing students at this last school. Gender analysis shows more conclusive results when referring to boys. In addition, students with a better learning concept have a greater decrease in cortisol levels. It is concluded that the students of the school with greater noise outside the classrooms present more unsatisfactory results for the evaluation of the cognitive performance, school performance and cortisol levels, in comparison to the students who study in the school with less noise outside the classrooms. Therefore, it is highlighted the importance of remodeling the existing school spaces and the elaboration of adequate constructive strategies when planning new buildings. It is important to emphasize the importance of urban space in the location of schools. Also, that this is a cross-sectional study, establishing a relationship between the variables analyzed. Finally, it is emphasized the need to deepen the theme, based on longitudinal studies, which evaluate the noise outside the classrooms for a longer period of time, also detecting the relationship of cause/effect between the noise levels outside the classrooms and cognitive performance, school performance, and students´ health indicators.