Green B G, Flammer L J
Monell Chemical Senses Center, Philadelphia, Pennsylvania 19104.
Somatosens Mot Res. 1989;6(5-6):553-66. doi: 10.3109/08990228909144692.
The ability to localize a chemical stimulus applied to the skin of the forearm was compared to the ability to localize a punctate tactile stimulus. The chemical stimulus was a single, 6-microliters drop of a 1.0% solution of capsaicin in an ethanol vehicle; the tactile stimulus was a polyester monofilament that exerted 7.5 g of force. Subjects attempted to localize the stimuli at 30-sec intervals for a period of 13.5 min, and rated the perceived intensity and quality of the chemogenic sensations. To avoid generating potentially confounding tactile sensations, localization attempts were made by pointing to the area of sensation with a focused light beam. The results showed that overall, chemical localization was inferior to tactile localization: The absolute error of localization averaged 2.5 cm for capsaicin compared to 1.4 cm for the monofilament. The experiment also revealed that chemical localization (1) varied significantly across arms, (2) exhibited a relatively strong bias toward the elbow, and (3) appeared to be unaffected by the perceived intensity of the sensation. The dominant sensation quality reported was itch. The results are discussed in the context of cutaneous localization in general and localization in the nociceptive system in particular.
将施加在前臂皮肤上的化学刺激的定位能力与点状触觉刺激的定位能力进行了比较。化学刺激是一滴6微升、浓度为1.0%的辣椒素乙醇溶液；触觉刺激是一根施加7.5克力的聚酯单丝。受试者每隔30秒尝试定位刺激，持续13.5分钟，并对化学感觉的感知强度和性质进行评分。为避免产生潜在的混淆触觉，通过用聚焦光束指向感觉区域来进行定位尝试。结果表明，总体而言，化学定位不如触觉定位：辣椒素定位的绝对误差平均为2.5厘米，而单丝为1.4厘米。实验还表明，化学定位（1）在双臂之间有显著差异，（2）表现出相对较强的向肘部的偏向，（3）似乎不受感觉感知强度的影响。报告的主要感觉性质是瘙痒。本文在一般皮肤定位尤其是伤害感受系统定位的背景下讨论了这些结果。
