Illich P A, King T A, Grau J W
Department of Psychology, Texas A&M University, College Station 77843, USA.
J Exp Psychol Anim Behav Process. 1995 Oct;21(4):331-47. doi: 10.1037//0097-7403.21.4.331.
Prior research has shown that exposure to shock can induce a decrease in pain reactivity (hypoalgesia). The present experiments show that, at the same time points that subjects are less responsive to radiant heat applied to the tail (the tail-flick test), tailshock elicits enhanced motor reactivity and vocalization. This enhanced responsiveness, or hyperalgesia, is observed with both magnitude (Experiment 1) and threshold (Experiment 2) measures and decays within 32 min (Experiment 2). Experiment 3 shows that the hyperalgesia decays irrespective of whether or not subjects remain in the shock context, which suggests that the loss of hyperalgesia does not reflect extinction of the context-shock association. Neither removing subjects from the shock context (Experiment 4) nor the presentation of a postshock distractor (Experiment 5) affected the hyperalgesia.
先前的研究表明，遭受电击会导致疼痛反应性降低（痛觉减退）。目前的实验表明，在受试者对施加于尾巴的辐射热反应较弱的同一时间点（甩尾试验），尾部电击会引发增强的运动反应性和发声。这种增强的反应性，即痛觉过敏，在强度（实验1）和阈值（实验2）测量中均有观察到，并在32分钟内衰减（实验2）。实验3表明，无论受试者是否仍处于电击环境中，痛觉过敏都会衰减，这表明痛觉过敏的消失并不反映环境 - 电击关联的消退。将受试者从电击环境中移出（实验4）或在电击后呈现干扰物（实验5）均未影响痛觉过敏。
