Dubno J R, Schaefer A B
Department of Otolaryngology and Communicative Sciences, Medical University of South Carolina, Charleston 29425.
J Acoust Soc Am. 1995 Feb;97(2):1165-74. doi: 10.1121/1.413057.
Thresholds in notched-noise maskers (NN) and narrow-band maskers (NB) were measured for normal-hearing and hearing-impaired subject pairs who were listening in a background of spectrally shaped broadband noise (SSBB). Consonant recognition was also measured in SSBB. SSBB was adjusted so that thresholds in that noise for each normal-hearing/hearing-impaired subject pair were equal. Threshold and signal-level differences between subject pairs were minimized with the addition of threshold-elevating SSBB, and the presence of a noise background for both groups provided a comparable listening environment for all subjects. At signal frequencies outside masker passbands, thresholds in NN and NB for hearing-impaired subjects were higher than for normal-hearing subjects, although threshold differences were much smaller than observed between normal-hearing and hearing-impaired subjects without SSBB. No consistent differences in consonant recognition measured in SSBB were observed between groups. The pattern of results is comparable to that observed in a previous experiment [Dubno and Schaefer, J. Acoust. Soc. Am. 91, 2110-2121 (1992)] in which thresholds in NN and NB, and consonant recognition, for hearing-impaired listeners were compared to results obtained for normal-hearing subjects, but only normal-hearing subjects listened in SSBB. Using a modified power-law model of masking additivity, thresholds in combined-masker conditions were estimated. Masking effects for spectrally overlapping maskers were similar for normal-hearing and hearing-impaired listeners and suggest that residual differences between subject groups are not due to the presence of an additional background noise.
在有频谱塑形宽带噪声（SSBB）的背景下，对听力正常和听力受损的受试者对进行了测量，以确定带凹口噪声掩蔽器（NN）和窄带掩蔽器（NB）中的阈值。还在SSBB中测量了辅音识别。调整SSBB，使每对听力正常/听力受损受试者在该噪声中的阈值相等。通过添加提高阈值的SSBB，使受试者对之间的阈值和信号电平差异最小化，并且两组都存在噪声背景为所有受试者提供了可比的聆听环境。在掩蔽器通带之外的信号频率处，听力受损受试者在NN和NB中的阈值高于听力正常的受试者，尽管阈值差异比在没有SSBB的听力正常和听力受损受试者之间观察到的要小得多。在SSBB中测量的辅音识别方面，两组之间未观察到一致的差异。结果模式与先前实验[Dubno和Schaefer，《美国声学学会杂志》91，2110 - 2121（1992）]中观察到的模式相似，在该实验中，将听力受损听众在NN和NB中的阈值以及辅音识别与听力正常受试者获得的结果进行了比较，但只有听力正常的受试者在SSBB中聆听。使用掩蔽叠加性的修正幂律模型，估计了组合掩蔽器条件下的阈值。对于听力正常和听力受损的听众，频谱重叠掩蔽器的掩蔽效果相似，这表明受试者组之间的残留差异不是由于存在额外的背景噪声。
