Laboratory Research On The Effects Of Environmental Noise On Children's Cognition

With the increasing of noise problems,the research about noise effects on human beings had become a very important research field.However,research subjects in most studies were adults rather than children.In this study,systematic laboratory experiments were carried out to clarify the adverse effects of environment noise on children's cognitive process such as attention,short term memory,reading and calculating.By doing that the characteristic of noise effects on children and its varying range and tendency were defined and the deficiency of basic research on children was made up.Firstly,social surveys were carried out,which showed that traffic noise and air-condition noise were the most common noise in children's daily lives.At the same time,the experienmental noises were obtained by live recording.Then,four experiments were carried out in a semi-anechoic room in turn.In each experiment,participants were asked to finish certain cognitive tasks with the broadcasting of white noise,air-condition noise and traffic noise.The noise level of each experimental noise varied from 35 dBA to 65 dBA with a step of 5d B.The results showed subjective annoyance evaluation was more sensitive to noise effects than task performance.Noise level was a significant factor to children's noise annoyance whatever noise source was.Children began to show a little annoyance when the noise level reached to 45dBA-50 dBA.The influence of different noise sources on four cognitive processes was different.Similar effect of air-condition noise was found in the four congnitive processes.However,the traffic noise had more obvious effects on short-term memery.The withe noise had more obvious effects on short-term memory and reading.Furthermore,the result showed that many non-acoustic factors,such as age and gender,could affect how children perceive the noises.