Department for Clinical Psychology, Psychotherapy, and Experimental Psychopathology, Johannes Gutenberg University Mainz, Germany.
Department for Clinical Psychology, Psychotherapy, and Experimental Psychopathology, Johannes Gutenberg University Mainz, Germany.
J Behav Ther Exp Psychiatry. 2019 Sep;64:106-112. doi: 10.1016/j.jbtep.2019.03.006. Epub 2019 Mar 29.
Nocebo hyperalgesia (i.e., increased pain sensitivity based on expectations) can be induced by conditioning, but is supposed to be mediated by conscious expectation. Although recent evidence points to the feasibility of subliminal conditioning of nocebo hyperalgesia with masked faces, face processing might be a special case and the practical implications of subliminal conditioning remain questionable. This study aimed to implicitly condition nocebo hyperalgesia using supraliminal cues.
Implicit differential nocebo conditioning (N = 48 healthy participants) was implemented by coupling high and low painful electric stimuli to varying visual stimuli that only differed in the symmetry/asymmetry of one component (CS+/CS-) and contained further distracting components. In the test phase, only the low painful stimulus followed both CS to test for conditioned nocebo effects in intensity and aversiveness ratings and electrodermal activity. A behavioral contingency test and a post-experimental questionnaire assessed contingency awareness.
A conditioned effect emerged in the aversiveness (p = .036; η = 0.09), but not in the intensity rating (p = .195) while controlling for contingency awareness. Further, increased skin conductance levels in response to CS + emerged, irrespective of contingency awareness (p = .014, η = 0.13). No conditioned responses in skin conductance responses emerged (p = .872).
Expected effects only emerged in part of the outcome variables.
The results support the notion that implicit conditioning of nocebo hypoalgesia is feasible using a novel experimental conditioning design with supraliminal stimulus presentation, although further research is needed. So far, implicitly conditioned nocebo effects might have been underestimated despite vast clinical implications.
基于预期的条件作用，可以产生无效安慰剂镇痛（即疼痛敏感性增加），但它应该是由有意识的预期介导的。尽管最近的证据表明，使用掩蔽面孔进行无效安慰剂镇痛的潜意识条件作用是可行的，但面部处理可能是一个特殊情况，潜意识条件作用的实际意义仍存在疑问。本研究旨在使用超显性线索来潜意识地调节无效安慰剂镇痛。
通过将高痛和低痛的电刺激与仅在一个组件（CS+/CS-）的对称性/非对称性上有所不同的不同视觉刺激相结合，实现了潜意识差异无效安慰剂条件作用（N=48 名健康参与者），并包含其他分散注意力的组件。在测试阶段，只有低痛刺激跟随两个 CS，以测试强度和厌恶评分以及皮肤电活动中的条件无效安慰剂效应。行为关联测试和实验后问卷评估了关联意识。
在厌恶感方面出现了条件效应（p=0.036；η=0.09），但在强度评分方面没有（p=0.195），同时控制了关联意识。此外，无论关联意识如何，CS+引起的皮肤电导水平均增加（p=0.014，η=0.13）。在皮肤电导反应中没有出现条件反应（p=0.872）。
预期的效果仅在部分结果变量中出现。
尽管需要进一步研究，但这些结果支持了这样一种观点，即使用具有超显性刺激呈现的新型实验条件作用设计，潜意识地调节无效安慰剂镇痛是可行的。到目前为止，尽管具有广泛的临床意义，但潜意识调节的无效安慰剂效应可能被低估了。
