AUDITORY FILTER SHAPES IN SUBJECTS WITH UNILATERAL AND BILATERAL COCHLEAR IMPAIRMENTS
AUDITORY FILTER SHAPES IN SUBJECTS WITH UNILATERAL AND BILATERAL COCHLEAR IMPAIRMENTS
复制标题
DOI：
10.1121/1.393374
复制
发表时间：
1986-04-01
影响因子：
2.4
通讯作者：
MOORE, BCJ
中科院分区：
文献类型：
--
作者：
GLASBERG, BR;MOORE, BCJ
听觉滤波器的形状估计在三个中心频率，0.5，1.0，和2.0 kHz，为5名受试者与单侧耳蜗损伤。在1.0 kHz下使用一名单侧损伤受试者和六名双侧损伤受试者进行额外测量。受试者被选择谁的阈值受损的耳朵是相对平坦的频率的函数，范围从15至70分贝HL。滤波器形状通过测量正弦信号（频率f）在两个噪声带（0.4 f宽，一个高于f，一个低于f）存在下的阈值来估计。噪声的频谱电平为50 dB（re：20 μ Pa），并且噪声频带关于信号频率对称和不对称地放置。每个噪声带的较近边缘与f的偏差在0.0 ~ 0.8f之间变化。对于正常的耳朵，过滤器是显着不对称的中心频率为1.0和2.0 kHz，高频分支是陡峭的。在0.5 kHz时，滤波器更加对称。对于受损的耳朵，滤波器的形状从一个主题到另一个主题变化很大。对于大多数受试者，滤器的下分支比正常情况下陡峭得多。上分支通常不像正常那么陡峭，但少数受试者显示接近正常的上分支。对于单侧损伤的受试者，在每个中心频率处，受损耳的等效矩形带宽总是大于正常耳的等效矩形带宽。对于0.5 kHz的三名受试者和1.0 kHz的一名受试者，滤波器对其形状的选择性太小，无法确定。
The shape of the auditory filter was estimated at three center frequencies, 0.5, 1.0, and 2.0 kHz, for five subjects with unilateral cochlear impairments. Additional measurements were made at 1.0 kHz using one subject with a unilateral impairment and six subjects with bilateral impairments. Subjects were chosen who had thresholds in the impaired ears which were relatively flat as a function of frequency and ranged from 15 to 70 dB HL. The filter shapes were estimated by measuring thresholds for sinusoidal signals (frequency f) in the presence of two bands of noise, 0.4 f wide, one above and one below f. The spectrum level of the noise was 50 dB (re: 20 .mu.Pa) and the noise bands were placed both symmetrically and asymmetrically about the signal frequency. The deviation of the nearer edge of each noise band from f varied from 0.0 to 0.8 f. For the normal ears, the filters were markedly asymmetric for center frequencies of 1.0 and 2.0 kHz, the high-frequency branch being steeper. At 0.5 kHz, the filters were more symmetric. For the impaired ears, the filter shapes varied considerably from one subject to another. For most subjects, the lower branch of the filter was much less steep than normal. The upper branch was often less steep than normal, but a few subjects showed a near normal upper branch. For the subjects with unilaterl impairments, the equivalent rectangular bandwidth of the filter was always greater for the impaired ear than for the normal ear at each center frequency. For three subjects at 0.5 kHz and one subject at 1.0 kHz, the filter had too little selectivity for its shape to be determined.