Smith P A, Ferguson M A
MRC Institute of Hearing Research, General Hospital, Nottingham, UK.
Br J Audiol. 1994 Jun;28(3):155-67. doi: 10.3109/03005369409086563.
Loudness recruitment and reduced frequency resolution both occur in cochlear types of hearing loss. One theory of loudness recruitment suggests that, as intensity is coded partly by spread of excitation across the nerve fibre array, recruitment is a direct consequence of the broad spread of excitation associated with poor frequency resolution. The present study investigated the relationship between these two quantities. The study involved a simple measure of frequency resolution (three-point psychoacoustical tuning curve, PTC) and conventional measures of recruitment obtained from patients undergoing neuro-otological investigation. Results from 376 ears of 226 patients without any material conductive impairment are presented. Measures of recruitment included the alternate binaural loudness balance test (ABLB) and estimates of dynamic range given by the sensation levels of the uncomfortable loudness level and the acoustic reflex threshold. Once covariation with hearing threshold level had been accounted for, no clear relationship emerged between frequency resolution and any of the measures of recruitment. This finding does not support the notion that frequency resolution and recruitment are specifically related. Rather, PTCs provide information complementary to measures of recruitment.
响度重振和频率分辨力下降都出现在耳蜗型听力损失中。一种关于响度重振的理论认为，由于强度部分是通过兴奋在神经纤维阵列上的扩散来编码的，因此重振是与频率分辨力差相关的广泛兴奋扩散的直接结果。本研究调查了这两个量之间的关系。该研究涉及一种简单的频率分辨力测量方法（三点心理声学调谐曲线，PTC）以及从接受神经耳科学检查的患者中获得的重振的常规测量方法。呈现了226例无任何实质性传导性损伤患者的376只耳朵的结果。重振的测量方法包括交替双耳响度平衡试验（ABLB）以及由不适响度级别的感觉水平和声反射阈值给出的动态范围估计值。一旦考虑了与听力阈值水平的协变量，频率分辨力与任何重振测量方法之间均未出现明确的关系。这一发现不支持频率分辨力与重振存在特定关联的观点。相反，PTC提供了与重振测量方法互补的信息。
