Physiological costs of the hearing of Chinese and European subjects exposed to noise and Chinese classical music

摘要

In four test series with an exposure level of 94 dB (A) for 1 hour, each, Chinese andEuropean subjects were exposed to Chinese classical music and noise. The physiologicalresponses of hearing were evaluated by temporary threshold shifts (TTS2), the restitutiontime, and the “Integrated Restitution Temporary Threshold Shifts” (IRTTS), i.e. the total“physiological costs” the hearing had to pay for. For Chinese subjects, the exposure toindustrial noise caused significantly higher TTS2 values and a considerably prolongedrestitution time than classical music. Also for European subjects, wide-band noise causedsignificantly higher TTS_2 values and longer restitution times than Chinese classical music.With respect to the ethnic groups, there is no significant difference in the TTS_2 values ofthe Chinese and European subjects after exposing to Chinese classical music and noise. Thetotal physiological costs of the Chinese subjects associated with classical music related tothose of industrial noise amounted to just 10%. Based on the conventional energyequivalent rating of sound exposures, the results should have been identical in the tests.This is not at all the case. Therefore, rating of sound exposures in accordance withtraditional procedures can lead to a grave misestimating of the actual physiological costs ofthe hearing.