International Journal of Occupational Hygiene (Apr 2018)
The Influences of Individual Sensitivity, Sound Frequency, and Sound Pressure Level on Cognitive Performances of Students
Abstract
Background: Low-frequency noise is annoying even at lower levels and affects cognitive functions of individuals. Some individual differences, such as sensitivity, can reduce or increase the effects of noise on cognitive performance. Materials and Methods: This study investigated the effect of noise sensitivity on cognitive performance in the presence of low-frequency noise. In this experimental study, 120 fourth-year seniors in the field of health sciences year from Hamadan University of Medical Sciences, Iran were selected through purposive sampling (60 students with high sensitivity and 60 students with low sensitivity). All the participants were exposed for 40 min to the noise levels of 50, 60, and 70 dB at the frequencies of 125 and 250 Hz, during which, the cognitive performance of the subjects was examined using the Integrative Visual-Auditory Continuous Performance Test (IVA CPT). Data were analyzed by independent t-test, and ANOVA test in SPSS 20.0 software. Results: The low-frequency noise negatively affected the components of cognitive performance so that with increasing the sound pressure level (SPL) from 50 to 70 dB and from 125 to 250 Hz (P<0.05), the components of cognitive performance decreased. The results also showed that in female subjects with high sensitivity, cognitive performance components were more affected than the male subjects with low sensitivity (P<0.05). Conclusion: The components of attention and work quality reduced with increasing SPL, and this negative effect of low-frequency noise was higher in women with high sensitivity.
