[Effect of noise on human mental performance].

OBJECTIVE To investigate the effect of moderate noise on human thinking performance. METHODS During 2 h of exposure to 85, 90 dB(A), successive calculation, successive subtraction and determining figures according symbol were performed in 24 healthy young male subjects. RESULTS After l h exposure to noise of 85 dB(A), there were no significant changes in the accurate rate, correct number and total number of successive calculation, but the correct number and total number of successive subtraction decreased significantly as compared with control (P< 0.05). At 30 and 120 min exposure to noise of 90 dB(A), the mean reaction time prolonged, performance of reaction time decrease significantly (P<0.01) in the test of determining figures according symbol as compared with control; its total performance had a tendency of decrease, but was not significant. When the subjects were divided into two group according to their E score of EPQ, significantly different performance of accurate rate and different total performance were demonstrated in the test of determining figures according to symbol at 2 h of exposure under 90 dB(A) noise. The performance of extrovert was higher than that of introvert. CONCLUSION Moderate noise could affect performance of complex tasks with a higher workload and it had certain relationship with the personality of the subjects.