Subjects in conditioning group were exposed to an octave band of noise(OBN) centered at 0.5kHz,95dB SPL,6 h per day for 10 days.

• 适应组先在实验室内暴露于强度为95 dB SPL(声压级)；中心频率为0.；5 kHz的一个倍频程噪声；连续10 d；每天6 h;