Katz-Salamon M
Acta Physiol Scand. 1984 Jan;120(1):43-51. doi: 10.1111/j.1748-1716.1984.tb07371.x.
Human ability to detect small changes in the inspired volume was tested in four healthy subjects. The tested volume changes were achieved by: 1) displaying breathing volume continuously to the subject on the screen of an oscilloscope, the vertical gain of which was changed by the experimenter, and 2) breathing small amounts of CO2 (0.02-2.0%) in air. The subject was asked to signal, by pressing a button, every time two consecutive breaths differed from the reference level. The six tested volume changes corresponded to 15-65% of the reference, when changes in eupneic tidal volume were tested, and to 15-45% when changes in three reference volume levels, 1.0, 1.5, and 2.0 times the resting tidal volume, were tested. The just noticeable difference (JND) was defined as the volume change detected in 50% of the trials. The obtained results showed that the JND for volume corresponds to a volume change of 120-160 ml (23-28% of the reference) when the resting tidal volume was used as the reference. For the three reference volumes, the JND was found to be a nearly constant fraction (0.25-0.29) of the reference volume and thus followed the 'classical' Weber law (JND/reference stimulus = constant).
在四名健康受试者身上测试了人类检测吸入气量微小变化的能力。通过以下方式实现测试的气量变化：1）在示波器屏幕上向受试者持续显示呼吸量，实验者改变示波器的垂直增益；2）在空气中呼吸少量二氧化碳（0.02 - 2.0%）。要求受试者每当连续两次呼吸与参考水平不同时按下按钮发出信号。测试的六种气量变化，在测试平静潮气量变化时相当于参考值的15 - 65%，在测试三种参考气量水平（静息潮气量的1.0、1.5和2.0倍）变化时相当于参考值的15 - 45%。将刚好可察觉差异（JND）定义为在50%的试验中检测到的气量变化。所得结果表明，当以静息潮气量作为参考时，气量的JND相当于120 - 160毫升的气量变化（占参考值的23 - 28%）。对于三种参考气量，发现JND是参考气量的一个几乎恒定的比例（0.25 - 0.29），因此遵循“经典”韦伯定律（JND/参考刺激 = 常数）。
