Mostauli Arasch, Rauh Jonas, Gamer Matthias, Büchel Christian, Rief Winfried, Brassen Stefanie
Department of Systems Neuroscience, University Medical Centre Hamburg-Eppendorf, Martinistrasse 52, D-20246, Hamburg, Germany.
Department of Psychology, University of Würzburg, D-97070, Würzburg, Germany.
Sci Rep. 2025 Mar 17;15(1):9088. doi: 10.1038/s41598-025-93589-y.
Clinical trials with antidepressants reveal significant improvements in placebo groups, with effects of up to 80% compared to real treatment. While it has been suggested that treatment expectations rely on cognitive control, direct evidence for affective placebo effects is sparse. Here, we investigated how cognitive resources at both the behavioral and neural levels influence the effects of positive expectations on emotional processing. Forty-nine healthy volunteers participated in a cross-over fMRI study where positive expectations were induced through an alleged oxytocin nasal spray and verbal instruction. Participants completed a spatial cueing task that manipulated attention to emotional face distractors while being scanned and were characterized regarding their general attention control ability. Placebo treatment improved mood and reduced distractibility from fearful compared to happy faces, particularly when more attentional resources were available for processing face distractors. This aligned with changes in activation and functional coupling within prefrontal-limbic networks, suggesting that expectations induce top-down regulation of aversive inputs. Additionally, neurobehavioral effects correlated with individual control ability. Our findings highlight the critical role of cognitive resources in verbally instructed placebo effects. This may be particularly relevant in patients with major depressive disorder, who often demonstrate enhanced negativity processing but have limited cognitive control capacity.
抗抑郁药物的临床试验显示，安慰剂组有显著改善，与实际治疗相比，效果高达80%。虽然有人认为治疗期望依赖于认知控制，但情感安慰剂效应的直接证据却很少。在这里，我们研究了行为和神经层面的认知资源如何影响积极期望对情绪加工的作用。49名健康志愿者参与了一项交叉功能磁共振成像研究，通过一种所谓的催产素鼻喷雾剂和口头指令诱导出积极期望。参与者在接受扫描时完成了一项空间线索任务，该任务操纵了对情绪化面部干扰物的注意力，并对他们的一般注意力控制能力进行了评估。与开心面孔相比，安慰剂治疗改善了情绪，并减少了对恐惧面孔的分心，尤其是当有更多注意力资源可用于处理面部干扰物时。这与前额叶-边缘系统网络内的激活和功能耦合变化相一致，表明期望会引发对厌恶输入的自上而下的调节。此外，神经行为效应与个体控制能力相关。我们的研究结果突出了认知资源在口头指令安慰剂效应中的关键作用。这对于重度抑郁症患者可能尤为重要，他们通常表现出更强的消极性加工能力，但认知控制能力有限。
