Stuart A, Phillips D P
Department of Psychology, Dalhousie University, Halifax, Nova Scotia, Canada.
Ear Hear. 1996 Dec;17(6):478-89. doi: 10.1097/00003446-199612000-00004.
Word recognition performance in continuous and interrupted broadband noise was examined in young normal-hearing (YNH), older normal-hearing (ONH), and presbyacusic (older hearing-impaired [OHI]) listeners.
Participants (N = 36) were presented with identical Northwestern University Auditory Test No. 6 stimuli at 30 dB sensation level re their respective speech reception thresholds. The speech stimuli were presented in quiet and in both competing noise conditions with signal to noise ratios (S/Ns) of 10, 5, 0, -5, -10, -15, and -20 dB.
In general performance was superior in quiet, improved with increasing S/N, and was greater in the interrupted broadband noise than in the continuous broadband noise. Significant main effects of group and S/N were found in both competing noises (p < 0.0001). Post hoc pairwise comparisons revealed all groups performed differently, with superior performance being displayed by the YNH group followed by the ONH and OHI groups, respectively (p < 0.05). A significant group by S/N interaction was observed in only the interrupted noise condition (p = 0.019). The degree of change in word recognition performance as a function of S/N was greatest in the OHI group followed by the ONH group and the YNH group.
Group effects observed in the interrupted noise would imply that the two older groups of listeners had an auditory temporal deficit relative to the YNH listeners. The paradigm reveals the patency of the temporal processes that are responsible for the perceptual advantage (i.e., a release from masking) a listener has in interrupted competing stimulus.
在年轻听力正常(YNH)、年长听力正常(ONH)和老年听力减退(OHI,即年长听力受损者)的听众中,研究了在连续和间断宽带噪声环境下的单词识别表现。
向36名参与者分别呈现相同的西北大学听觉测试第6号刺激声,强度为高于其各自言语接受阈值30 dB的感觉级。言语刺激在安静环境以及两种竞争噪声环境中呈现,信噪比(S/N)分别为10、5、0、-5、-10、-15和-20 dB。
总体而言,安静环境下的表现最佳,随着信噪比增加而改善,且在间断宽带噪声环境中的表现优于连续宽带噪声环境。在两种竞争噪声环境中均发现了显著的组间和信噪比主效应(p < 0.0001)。事后两两比较显示,所有组的表现均不同,YNH组表现最佳,其次是ONH组和OHI组(p < 0.05)。仅在间断噪声环境中观察到显著的组×信噪比交互作用(p = 0.019)。单词识别表现随信噪比变化的程度在OHI组中最大,其次是ONH组和YNH组。
在间断噪声中观察到的组间效应表明,与YNH听众相比,两个年长听众组存在听觉时间缺陷。该范式揭示了负责听众在间断竞争刺激中具有感知优势(即掩蔽解除)的时间过程的通畅性。