Auditory filter bandwidths were measured using nonsimultaneous masking, as a function of signal level between 10 and 35 dB SL for signal frequencies of 1, 2, 4, and 6 kHz. The brief sinusoidal signal was presented in a temporal gap within a spectrally notched noise. Two groups of normal-hearing subjects were tested, one using a fixed masker level and adaptively varying signal level, the other using a fixed signal level and adaptively varying masker level. In both cases, auditory filters were derived by assuming a constant filter shape for a given signal level. The filter parameters derived from the two paradigms were not significantly different. At 1 kHz, the equivalent rectangular bandwidth (ERB) decreased as the signal level increased from 10 to 20 dB SL, after which it remained roughly constant. In contrast, at 6 kHz, the ERB increased consistently with signal levels from 10 to 35 dB SL. The results at 2 and 4 kHz were intermediate, showing no consistent change in ERB with signal level. Overall, the results suggest changes in the level dependence of the auditory filters at frequencies above 1 kHz that are not currently incorporated in models of human auditory filter tuning.
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机译:对于1、2、4、6 kHz的信号频率,使用非同时屏蔽来测量听觉滤波器的带宽,作为信号电平在10 dB dB至35 dB SL之间的函数。在频谱缺口噪声内的时间间隙中呈现了简短的正弦信号。测试了两组正常听觉受试者,一组使用固定的掩蔽水平和自适应变化的信号水平,另一组使用固定的信号水平和自适应变化的掩蔽水平。在这两种情况下,通过假设给定信号电平的滤波器形状恒定,可以得出听觉滤波器。从这两种范例中得出的滤波器参数没有显着差异。在1 kHz时,当信号电平从10 dB SL增加到20 dB SL时,等效矩形带宽(ERB)减小,此后大致保持恒定。相反,在6 kHz时,ERB随信号电平从10 dB到35 dB SL一致增加。在2 kHz和4 kHz处的结果是中间的,表明ERB随信号电平没有一致的变化。总的来说,这些结果表明,听觉滤波器的电平依赖性在高于1 kHz的频率上发生了变化,这些变化目前尚未纳入人类听觉滤波器调整模型中。
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