Lautenbacher S, Galfe G, Hölzl R, Strian F
Max Planck Institute for Psychiatry Clinical Department, Munich, Federal Republic of Germany.
Percept Mot Skills. 1989 Oct;69(2):579-89. doi: 10.2466/pms.1989.69.2.579.
To assess temporal variations in the perception of "phasic" heat pain stimuli a psychophysical tracking procedure was developed that enables repeated assessment of the pain threshold at short intervals. This "double-tracking" procedure produces two tracking curves simultaneously, one that approaches the pain threshold gradually from above, the other from below. The threshold for phasic heat pain was measured in 80 tracking trials with stimuli at temperatures near the pain threshold. Concurrently, the threshold for "tonic" heat pain was determined after every 20 tracking trials with a stimulus adjustment procedure. Eleven healthy subjects (age: 26.4 yr. +/- 6.0) participated in 2 sessions each. Phasic stimulation near the pain threshold did not produce any trends in either of the two threshold measures. Hence there was no long-term adaptation or sensitization. However, there were random variations (random walks) in the tracking curves, which we interpret as resulting from a stochastic relationship between stimulus and sensation. In agreement with other reports, discrimination seemed to be better at painful than at nonpainful temperatures.
为了评估对“相位性”热痛刺激感知的时间变化，开发了一种心理物理学追踪程序，该程序能够在短时间间隔内对痛阈进行重复评估。这种“双追踪”程序同时产生两条追踪曲线，一条从上方逐渐接近痛阈，另一条从下方逐渐接近痛阈。在80次追踪试验中，使用接近痛阈温度的刺激测量相位性热痛的阈值。同时，每20次追踪试验后，通过刺激调整程序确定“持续性”热痛的阈值。11名健康受试者（年龄：26.4岁±6.0岁）每人参加了2次实验。接近痛阈的相位性刺激在两种阈值测量中均未产生任何趋势。因此，不存在长期适应或敏化现象。然而，追踪曲线中存在随机变化（随机游走），我们将其解释为刺激与感觉之间的随机关系所致。与其他报告一致，在疼痛温度下的辨别似乎比在非疼痛温度下更好。
