Effects of Long-term Exposure to Noise on Psychophysiological Responses

소음에 장기 노출되었을 때 나타나는 심리생리적 효과

It is well known that a long-term exposure to a loud noise environment affects performance, since it distracts attention, and also is able to evoke stress accompanied by negative emotional states. The purpose of this study was to analyze dynamics of subjective and physiological variables during long-lasting (30 min) exposure to intensive white noise (85 dB[A]). Physiological signals on 23 college students were recorded by BIOPAC, Grass Neurodata systems and AcqKnowledge 3.5 software. Autonomic variables, namely skin conductance level (SCL), non-specific SCR number (N-SCR), inter-beat intervals in ECG (RR intervals), heart rate variability index (HF/LF ratio of HRV), respiration rate (RESP), and skin temperature (SKT) were analyzed on 5 min epoch basis. Psychological assessment (subjective rating of stress level) was also repeated on every 5 min basis. Regression and correlation analyses were employed to trace the time course of the dynamics of the subjective and autonomic physiological variables and their relationship. Results showed that intense noise evokes subjective stress with associated autonomic nervous system responses. However, it was shown that physiological variables endure specific changes in the process of exposure to loud white noise. Discussed are probable psychophysiological mechanisms mediating reactivity to long-term auditory stimulation of high intensity.