Stillman J A, Zwislocki J J, Zhang M, Cefaratti L K
Institute for Sensory Research, Syracuse University, New York 13244.
J Acoust Soc Am. 1993 Jan;93(1):425-34. doi: 10.1121/1.405622.
The relationship between loudness level and intensity discrimination was investigated in the frequency range 0.5-6.5 kHz by comparing the intensity just-noticeable differences (jnd's) at a number of equal-loudness levels in the better and poorer ears of eight individuals with essentially unilateral hearing loss of cochlear origin. Such hearing loss usually produces loudness recruitment, altering the relationships among the loudness, sound-pressure level (SPL), and sensation-level (SL) variables, so that their effects can be separated. In these experiments, the jnd's were correlated with loudness level, not SPL or SL. Although, in some listeners, there were significant differences between jnd's in the two ears at some binaurally equal-loudness levels, they were not systematic over the group of listeners. Statistically, there was no significant difference between equal-loudness jnd's in the two ears, whereas the corresponding SLs and SPLs were significantly different. The rate of loudness growth had no effect on the jnd's. As expected from the near-miss to Weber's law, the mean jnd's decreased with sound intensity. The corresponding decrease in the mean Weber fraction, delta I/I, was accompanied by a decrement in its intrasubject standard deviation. The latter was correlated with the mean, independent of its relationship to SPL or SL.
通过比较八名患有耳蜗性单侧听力损失的个体中较好耳和较差耳在多个等响度水平下的强度刚可察觉差异（jnd），研究了0.5 - 6.5千赫频率范围内响度水平与强度辨别之间的关系。这种听力损失通常会导致响度重振，改变响度、声压级（SPL）和感觉级（SL）变量之间的关系，从而能够区分它们的影响。在这些实验中，jnd与响度水平相关，而非与SPL或SL相关。尽管在某些双耳等响度水平下，一些受试者双耳的jnd存在显著差异，但在所有受试者群体中差异并不具有系统性。从统计学角度来看，双耳等响度jnd之间没有显著差异，而相应的SL和SPL则存在显著差异。响度增长速率对jnd没有影响。正如对韦伯定律的近似情况所预期的那样，平均jnd随声音强度降低。平均韦伯分数ΔI/I的相应降低伴随着其受试者内标准差的减小。后者与平均值相关，与它和SPL或SL的关系无关。
