Department of Speech and Hearing Science, The Ohio State University, Columbus, Ohio 43210, USA.
J Acoust Soc Am. 2011 Feb;129(2):876-87. doi: 10.1121/1.3518778.
Low-frequency masking by intense high-frequency noise bands, referred to as remote masking (RM), was the first evidence to challenge energy-detection models of signal detection. Its underlying mechanisms remain unknown. RM was measured in five normal-hearing young-adults at 250, 350, 500, and 700 Hz using equal-power, spectrally matched random-phase noise (RPN) and low-noise noise (LNN) narrowband maskers. RM was also measured using equal-power, two-tone complex (TC2) and eight-tone complex (TC8). Maskers were centered at 3000 Hz with one or two equivalent rectangular bandwidths (ERBs). Masker levels varied from 80 to 95 dB sound pressure level in 5 dB steps. LNN produced negligible masking for all conditions. An increase in bandwidth in RPN yielded greater masking over a wider frequency region. Masking for TC2 was limited to 350 and 700 Hz for one ERB but shifted to only 700 Hz for two ERBs. A spread of masking to 500 and 700 Hz was observed for TC8 when the bandwidth was increased from one to two ERBs. Results suggest that high-frequency noise bands at high levels could generate significant low-frequency masking. It is possible that listeners experience significant RM due to the amplification of various competing noises that might have significant implications for speech perception in noise.
低频被高强度高频噪声带掩蔽，称为远程掩蔽（RM），这是第一个挑战信号检测的能量检测模型的证据。其潜在机制尚不清楚。在 250、350、500 和 700 Hz 处，使用等功率、光谱匹配随机相位噪声（RPN）和低噪声噪声（LNN）窄带掩蔽器，在五名正常听力的年轻成年人中测量 RM。还使用等功率、双音复合（TC2）和八音复合（TC8）测量 RM。掩蔽器的中心频率为 3000 Hz，带宽为一个或两个等效矩形带宽（ERB）。掩蔽器的声压级从 80 到 95 dB，每隔 5 dB 变化一次。对于所有条件，LNN 产生的掩蔽作用可以忽略不计。RPN 带宽增加会在更宽的频率范围内产生更大的掩蔽作用。对于一个 ERB，TC2 的掩蔽作用仅限于 350 和 700 Hz，但对于两个 ERB，掩蔽作用仅转移到 700 Hz。当带宽从一个 ERB 增加到两个 ERB 时，TC8 的掩蔽作用扩展到 500 和 700 Hz。结果表明，高电平的高频噪声带可能会产生显著的低频掩蔽。由于各种竞争噪声的放大，听众可能会经历显著的 RM，这可能对噪声中的言语感知产生重大影响。
