Zhang L F, Wu X Y, Jiang S Z, Zhang R, Xiao Z Y, Ma M C
Department of Aviation Environmental Physiology, Fourth Military Medical College, Xi'an.
Sci Sin B. 1988 Feb;31(2):204-16.
This paper presents and discusses the methodology and results of studies on respiratory sensation by using a fuzzy set category judgement model and applying the concept of just noticeable difference (JND) step and equivalent sensation. A new kind of category scale, the multistage evaluation scale (MES), based on a fuzzy set category judgement model for quantifying respiratory sensory magnitude has been put forward and verified in 37 subjects. The perceived magnitude of added resistance estimated using MES could reflect properly the difference in sensory perception caused by added loads with equal intensity but applied to different phases of the breathing cycle. In addition, the psychophysical function obtained conforms to the Stevens' power law. On the contrary, the classical category scale does not possess some of these attributes. In 9 subjects, we determined that the sensory continuum corresponding to either inspiratory or expiratory added resistive load, ranging 10-500 mm H2O.1(-1).s, consisted of 6 or 7 JND steps. The sensory magnitude corresponding to each step was estimated by the MES. Relating the results of JND step measurements with that of magnitude estimation using MES, we could elucidate systematically the relationship between perceived magnitude and discrimination for respiratory sensation. In 13 subjects, the equivalent respiratory resistive load sensation contours of 2, 3 and 4 JND step above basal level, respectively, were obtained through experimentation and by quadratic polynomial approximation of experimental data. The results suggest that as regards the human tolerance to various added resistive loads the combined resistive load is the most tolerable among the three; the expiratory, the least. The equivalent sensation contour can be used to predict the changes in respiratory sensation determined by both the intensity of the total added load and the ratio of inspiratory versus expiratory load. In brief, we have proposed a new way to elucidate the physiological and psychophysical effects of various added resistive loads.
本文介绍并讨论了通过使用模糊集类别判断模型以及应用恰可察觉差（JND）步长和等效感觉概念来研究呼吸感觉的方法和结果。基于用于量化呼吸感觉强度的模糊集类别判断模型，提出了一种新型类别量表——多级评估量表（MES），并在37名受试者中进行了验证。使用MES估计的附加阻力的感知强度能够恰当地反映同等强度但施加于呼吸周期不同阶段的附加负荷所引起的感觉差异。此外，所获得的心理物理函数符合史蒂文斯幂定律。相反，经典类别量表并不具备其中一些特性。在9名受试者中，我们确定对应于吸气或呼气附加阻力负荷（范围为10 - 500 mmHg·s⁻¹）的感觉连续体由6或7个JND步长组成。通过MES估计每个步长对应的感觉强度。将JND步长测量结果与使用MES进行强度估计的结果相关联，我们能够系统地阐明呼吸感觉的感知强度与辨别力之间的关系。在13名受试者中，通过实验以及对实验数据进行二次多项式近似，分别获得了比基础水平高2、3和4个JND步长的等效呼吸阻力负荷感觉等值线。结果表明，就人体对各种附加阻力负荷的耐受性而言，组合阻力负荷在三者中最易耐受；呼气阻力负荷最不易耐受。等效感觉等值线可用于预测由总附加负荷强度以及吸气与呼气负荷之比所决定的呼吸感觉变化。简而言之，我们提出了一种新方法来阐明各种附加阻力负荷的生理和心理物理效应。
