Department of Psychology, The University of Tulsa, USA.
Pain. 2010 Feb;148(2):320-327. doi: 10.1016/j.pain.2009.11.018. Epub 2009 Dec 22.
The Emotional Controls of Nociception (ECON) paradigm involves the presentation of emotionally-charged pictures during which painful stimuli are delivered. Across several ECON studies, unpleasant pictures enhanced pain and nociception, whereas pleasant pictures inhibited pain and nociception. However, at this time it is unknown whether emotional valence (unpleasant, neutral, pleasant) influences the habituation or sensitization of pain responses that occurs within a testing session. Indeed, ECON assumes that emotional valence modulation of pain is consistent throughout testing; otherwise the interpretation of valence modulation (unpleasant>neutral>pleasant) could be threatened. To address this issue, the present study (N=120) presented 108 pictures that varied in emotional valence. During and in between pictures, 52 suprathreshold electrocutaneous stimuli were delivered to evoke pain, the nociceptive flexion reflex [NFR], and pain-evoked skin conductance response [SCR]. Mixed effects ANOVAs verified that within-subject changes in pain responses were influenced by stimulus repetition (NFR and SCR habituated, pain ratings sensitized) and emotional valence (responses were highest during unpleasant pictures, intermediate during neutral pictures, and lowest during pleasant pictures). However, habituation/sensitization slopes were unaffected by emotional valence, thus indicating emotional valence modulation was consistently observed throughout the testing session. These results provide additional validation for the ECON paradigm and suggest that the circuit responsible for emotional modulation of pain and nociception is less susceptible to habituation or sensitization than the circuits responsible for responses to suprathreshold shocks.
伤害感受的情绪控制（ECON）范式涉及在呈现情绪化图片的同时给予疼痛刺激。在多项 ECON 研究中，不愉快的图片增强了疼痛和伤害感受，而愉快的图片抑制了疼痛和伤害感受。然而，目前尚不清楚情绪效价（不愉快、中性、愉快）是否会影响测试过程中疼痛反应的习惯化或敏感化。事实上，ECON 假设情绪效价对疼痛的调制是一致的；否则，对效价调制（不愉快>中性>愉快）的解释可能会受到威胁。为了解决这个问题，本研究（N=120）呈现了 108 张具有不同情绪效价的图片。在图片呈现期间和图片之间，给予 52 次超阈值电皮肤刺激以引起疼痛、伤害性屈肌反射[NFR]和疼痛诱发的皮肤电反应[SCR]。混合效应方差分析证实，个体内疼痛反应的变化受刺激重复（NFR 和 SCR 习惯化，疼痛评分敏感化）和情绪效价（不愉快的图片反应最高，中性图片反应居中，愉快的图片反应最低）的影响。然而，习惯化/敏感化斜率不受情绪效价的影响，这表明情绪效价调制在整个测试过程中始终存在。这些结果为 ECON 范式提供了额外的验证，并表明负责疼痛和伤害感受情绪调制的电路比负责超阈值冲击反应的电路更不易受到习惯化或敏感化的影响。
