Planned fMRI study to investigate neurobehavioral mechanisms of expectation effects on emotional processing

Understanding how expectations influence emotions is crucial for developing interventions for mood disorders. Current treatments often fall short, and the placebo effect, driven by expectations, demonstrates a powerful but poorly understood mechanism. While top-down cognitive control is known to induce instruction-based placebo effects, the role of more automatic mechanisms shaped by learning and past experiences in affective placebo responses remains largely unknown. This study aims to bridge this gap by examining both cognitive and experiential influences on emotional processing.

Researchers are recruiting N = 51 healthy adults (50% women) for a cross-over fMRI study. Participants will undergo two conditions: a positive expectation induction (placebo) and a control condition with no induced expectations. During each condition, participants will perform an emotion classification task. The study design aims to isolate the neurobehavioral mechanisms by which expectations and prior experiences modulate emotional processing, using brain imaging to identify neural correlates of these effects.

This study is designed to investigate specific hypotheses rather than reporting findings. The investigators hypothesize that positive expectations will enhance mood and improve the accuracy of recognizing happy facial expressions. Furthermore, they anticipate that affective expectations will be represented in fMRI signal patterns within neural networks involved in face perception, emotional processing, and cognitive control. > The primary goal is to map the neurobehavioral mechanisms of how expectations and prior experiences modulate emotional processing, providing insights into the neural underpinnings of the placebo effect. No specific numerical results or statistical outcomes are available yet, as this describes a planned experimental protocol.