A simple alternative to nondeceptive placebos for reducing emotional distress: encouragement

Abstract

Although numerous studies have shown that nondeceptive placebos (NDPs) can reduce emotional distress, research on their neurobiological effects remains limited. Furthermore, administering NDPs is time-consuming, as their effectiveness relies on providing detailed explanations of the concept and presumed mechanisms. This functional magnetic resonance imaging (fMRI) study investigated whether an encouragement-based intervention could serve as an alternative to NDPs. Three groups of female participants (total n=151) took part in an fMRI study in which they viewed both disgusting and neutral images. Prior to this, one group received an NDP capsule for oral intake, while another received a small figurine accompanied by an encouraging written message. Both interventions were framed as tools to support emotion regulation. A third group passively viewed the images. NDP and encouragement elicited similar, modest reductions in reported disgust. However, the two interventions were linked to distinct patterns of brain activity and connectivity, involving the putamen, hippocampus, and ventrolateral prefrontal cortex. Since participants perceived encouragement as a more credible and effective means of reducing emotional distress, it may serve as a simple and practical alternative to NDP pills.