作業者の聴力損失(PTS)の測定ならびにPTSと言語聴力障害との関連

本研究探讨了工业噪声诱发的工人永久性阈值移位及其与言语感知障碍的关系。研究结果与实验结果如下：对510名噪声暴露工人和325名非噪声暴露者的听力阈值进行了测量。2. 每个工人的噪音暴露量是通过个人噪音剂量计测量的，该计在特定的平均时间内给出等效的连续a加权声压级。3. 测量了噪声诱发PTS受试者和正常受试者的单音节单词发音。研究发现，单音节词的言语听力测试对听力损伤不敏感。4. 在环境噪声和混响条件下，对听力受损和正常受试者的三音节词发音进行了测量。结果表明，听障者的语音感知受混响的影响更大。5. 模拟招募现象的数字滤波器被编程并合成了假定听力受损者可能听到的失真声音。6. 使用正常受试者测量上述合成的单音节发音，并将结果表示为语音听像图，与使用未失真声音的恐惧障碍受试者进行比较。结果表明，两种听音图的一致性较好。

This study investigates the permanent threshold shift(PTS) of workers induced by industrial noise exposure and the relation between PTS and the impairment of speech perception. The results of the investigations and the experiments are as follows;1. Hearing thresholds of 510 noise-exposed workers and 325 subjects without noise exposure are measured. 2. Noise exposure of each worker is measured by means of indivifual noise dose meter which gives equivalent continuous A-Weighted Sound Pressure Level over the particular averaging time. 3. Articulations of monosyllabic words using the subjects having noise-induced PTS as well as normal subjects are measured. It is found that speech hearing test using monosyllabic words is not sensitive to hearing impairment. 4. Articulations of trisllabic words using the hearing impaired and normal subjects having NIPTS are measured in the presence of ambient noise and in the condition of reverberation. The results show that the hearing impaired are more imfluenced by reverberation in speech perception. 5. Digital filter simulating the recruitment phenomenon is programmed and distroted vocal sounds presumed the hearing impaired might hear are synthesized. 6. Articulations of monosyllabic sounds synthesized as above are measured using normal subjects and the result expressed as speech audiogramme are compared with that of the fearing impaired using notdistorted vocal sounds. The result shows that both audiogrammes are in satisfactory agreement.