騒音性一過性聴力損失に関する研究

Abstract

NITTS at C5 dip and its recovery process were experimentally observed after 1 hour exposure to some noises which were characterized with the octave-band filter, as white noise, high cut noise, and low cut noise. The subjects were 11 healthy men aged 22∼32 years and 7 healthy women aged 20∼24 years. And the results were as follows: 1) The dip was appeared more deeply in the exposures to white and low cut noises at higher sound levels than the others. But the recovery curves from the dip were shown almost parallel in the time scale, without concerning the differences of the dip values. 2) Individual differences, especially sexual differences were observed in the value and the recovery process of the dip, after 1 hour exposure to white noise in 90∼95 phones; women had little loss in the value of NITTS and showed more rapid recovery process, compared with men. 3) In preventive administrations of adrenochrom, chondroitin sulfate, and thiamine propyldisulfide, significant improvements on the recovery process were observed at the dip. But as for the dip value, no significant difference was observed between the control and the administered groups. 4) In order to resolve the sexual differences in the dip and its recovery process, we administered testosterone to women, and estradiol and estriol to men. In testosterone administration, the dip and its recovery process tended to grow worse, but no significant differences were observed between the control and the experimental groups of women. While significant improvements on the dip and its recovery process were observed in administrations of estradiol and estriol to men. 5) From the results of 4), the sexual differences in the dip and its recovery process seem to appear as an affection of follicular hormones.