Expectation Effects on Emotional Processing

Understanding the mechanisms underlying expectation effects in the affective domain can provide valuable insights into possible therapeutic interventions for mood disorders. Studies have consistently found that expectations can influence emotional experiences. Recently, it has been shown that top-down cognitive control is critical in inducing instruction-based affective placebo effects. However, changes in the emotional system over time not only rely on higher-level cognitive processes but also on more automatic mechanisms shaped by learning and past experiences. How such mechanisms are involved in affective placebo effects is relatively unknown, but is particularly interesting in light of findings showing that previous experiences of successful treatments are an important determinant of placebo responses. This study aims to investigate the neurobehavioral mechanisms of how expectations and prior experiences modulate emotional processing. Healthy adults (N = 51, 50% women) will be recruited to participate in a cross-over fMRI study involving two conditions: positive expectation induction (placebo) and a control condition with no induced expectations. Participants will perform an emotion classification task under each condition. The investigators hypothesize that positive expectations enhance mood and improve the accuracy of recognizing happy facial expressions. Further, they hypothesize that affective expectations are represented in fMRI signal patterns in networks involved in face perception, emotional processing, and cognitive control.

NCT Number	NCT07031804
Lead Sponsor	Universitätsklinikum Hamburg-Eppendorf
Conditions	Expectation Effects on Emotional Processing
Enrollment	51 participants
Start Date	2025-06
Primary Completion	2026-01 (estimated)
Study Completion	2026-01 (estimated)
Updated on ClinicalTrials.gov	2025-06-27