Background and objectives

For many psychotherapies, like Eye Movement and Desensitization Reprocessing (EMDR) therapy, there is an ongoing discussion about the role of specific versus non-specific mechanisms in their effectiveness However, experimental research directly examining the potential role of non-specific mechanisms is scarce. Here, we address the role of a non-specific factor that is often put forward for EMDR, namely treatment effectiveness expectations, within a laboratory model of EMDR therapy.

Methods

In a lab-based (N = 96) and an online experiment (N = 173), we gave participants verbal instructions to manipulate their treatment expectations. Instructions emphasized EMDR's effectiveness or ineffectiveness. Then, participants were asked to recollect an unpleasant autobiographical memory with or without making eye-movements.

Results

In line with previous studies, we found significant reductions of reported vividness and emotionality of negative autobiographical memories in the eye-movements condition. These reductions did not differ between the verbal suggestions conditions in both experiments, suggesting a limited effect of treatment effectiveness suggestions.

Limitations

Treatment effectiveness expectations were not successfully manipulated by the suggestions manipulation. This suggests that treatment expectations may be more difficult to influence than anticipated, thus limiting the interpretation of our findings.

Conclusions

These findings tentatively corroborate the results of two earlier reports, suggesting that the effects of verbal suggestions about treatment effectiveness in a laboratory model of EMDR therapy may be limited.

中文翻译：

---

口头建议未能调节对 EMDR 治疗实验室模型有效性的预期：两项预注册研究的结果

背景和目标

对于许多心理疗法，如眼球运动和脱敏再处理 (EMDR) 疗法，关于特定与非特定机制在其有效性中的作用的讨论正在进行中。然而，直接检验非特定机制潜在作用的实验研究很少。在这里，我们讨论了在 EMDR 治疗的实验室模型中经常为 EMDR 提出的非特异性因素的作用，即治疗效果预期。

方法

在基于实验室的 ( N  = 96) 和在线实验 ( N  = 173) 中，我们给参与者口头指示以操纵他们的治疗期望。说明强调了 EMDR 的有效性或无效性。然后，参与者被要求回忆一段不愉快的自传记忆，无论是否有眼球运动。

结果

与之前的研究一致，我们发现在眼球运动条件下，负面自传记忆的生动性和情绪性显着降低。这些减少在两个实验中的口头建议条件之间没有差异，表明治疗效果建议的效果有限。

限制

建议操纵并未成功操纵治疗效果预期。这表明治疗预期可能比预期更难以影响，从而限制了对我们研究结果的解释。

结论

这些发现初步证实了两份早期报告的结果，表明在 EMDR 治疗的实验室模型中，口头建议对治疗效果的影响可能是有限的。