Performance in detecting a 50 ms pure-tone signal in a longer tone-burst masker was evaluated as a function of the delay between masker and signal onset. Delays from 500 ms to 5 s were used, and detection was measured in terms of sensitivity d'. Performance was also measured for a continuous masker. In a first experiment, the masker and the signal had the same frequency (500, 1000, 2000, 4000 and 8000 Hz). In this case, sensitivity increased with delay for high frequencies and for high masker levels. In a second experiment, the masker and the signal had different frequencies; the masker was set at 4 kHz and the signal frequency was inside and outside the critical band of the masker. For this second case, the results depended on masker level and signal frequency: increasing the delay for a 50 dB SL masker did not improve detection; at 80 dB SPL, however, delaying the signal improved detection for signal frequencies close to the masker frequency. The assumption is made that the improved detection for long durations of the masker originates from a long-term decrease in the firing rate of the auditory nerve fibers. [References: 40]
展开▼
机译：评估了在较长的音频脉冲串掩蔽器中检测到50 ms纯音信号的性能，它是掩蔽器和信号开始之间的延迟的函数。使用500 ms至5 s的延迟，并根据灵敏度d'进行检测。还测量了连续掩膜机的性能。在第一个实验中，屏蔽器和信号具有相同的频率（500、1000、2000、4000和8000 Hz）。在这种情况下，对于高频和高掩蔽水平，灵敏度会随着延迟而增加。在第二个实验中，掩蔽器和信号具有不同的频率。屏蔽器设置为4 kHz，信号频率在屏蔽器的临界频带之内和之外。对于第二种情况，结果取决于掩蔽器电平和信号频率：增加50 dB SL掩蔽器的延迟不会改善检测效果;但是，在80 dB SPL时，延迟信号会改善对接近掩蔽频率的信号频率的检测。作出这样的假设，即对于长时间的掩蔽器的改进的检测源于听神经纤维的发射速率的长期降低。 [参考：40]
展开▼
