Comodulation masking release for various monaural and binaural combinations of the signal, on-frequency, and flanking bands.
Comodulation masking release for various monaural and binaural combinations of the signal, on-frequency, and flanking bands.
复制标题
针对信号、同频和侧翼频带的各种单耳和双耳组合的共调制掩蔽释放。
DOI：
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发表时间：
1989
影响因子：
2.4
通讯作者：
Brian C. J. Moore
中科院分区：
文献类型：
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作者：
G. P. Schooneveldt;Brian C. J. Moore
通过将包络与第一频带的包络相关的第二噪声频带（侧翼频带）添加到掩蔽器，可以降低由以信号频率为中心的窄带噪声（在频频带）掩蔽的信号的阈值。这种效应被称为共调节掩蔽释放（CMR）。这些实验考察了两个问题。(1)CMR如何随侧翼带的数量和出现穗而变化？(2)当双耳掩蔽电平差（BMLD）已经存在时，是否可以获得CMR，反之亦然？在以250、1000和4000 Hz的信号频率（fs）为中心的连续25 Hz宽的噪声中，测量400 ms信号的持续时间。这个掩蔽信号可以单独出现，也可以与一个或多个连续的侧翼带一起出现，侧翼带的包络与频率上的频带相关或不相关;它们的频率范围从0.5fs到1.5fs。在六种条件下测量CMR，其中信号、频率上的频带和侧翼频带以各种单声道和双耳组合呈现。当使用单个侧翼频带时，CMR通常在2- 3dB左右。如果增加额外的侧翼频带，CMR增加到5- 6dB。无论是在与原始带相同的耳中还是在对侧耳中，附加带的效果都相似。在最低信号频率下，除了BMLD之外还观察到大的CMR，反之亦然。在最高信号频率下，掩蔽的额外释放很小。结果解释的线索产生的CMR和BMLD。
The threshold for a signal masked by a narrow band of noise centered at the signal frequency (the on-frequency band) may be reduced by adding to the masker a second band of noise (the flanking band) whose envelope is correlated with that of the first band. This effect is called comodulation masking release (CMR). These experiments examine two questions. (1) How does the CMR vary with the number and ear of presentation of the flanking band(s)? (2) Is it possible to obtain a CMR when a binaural masking level difference (BMLD) is already present, and vice versa? Thresholds were measured for a 400-ms signal in a continuous 25-Hz-wide noise centered at signal frequencies (fs) of 250, 1000, and 4000 Hz. This masker was presented either alone or with one or more continuous flanking bands whose envelopes were either correlated or uncorrelated with that of the on-frequency band; their frequencies ranged from 0.5fs to 1.5fs. CMRs were measured for six conditions in which the signal, the on-frequency band, and the flanking band(s) were presented in various monaural and binaural combinations. When a single flanking band was used, the CMR was typically around 2-3 dB. The CMR increased to 5-6 dB if an additional flanking band was added. The effect of the additional band was similar whether it was in the same ear as the original band or in the opposite ear. At the lowest signal frequency, a large CMR was observed in addition to a BMLD and vice versa. At the highest signal frequency, the extra release from masking was small. The results are interpreted in terms of the cues producing the CMR and the BMLD.