The Many Smiles Collaboration: A Multi-Lab Foundational Test of the Facial Feedback Hypothesis

The facial feedback hypothesis suggests that an individual’s subjective experience of emotion is influenced by their own facial expressions. However, researchers currently face conflicting narratives about whether this hypothesis is valid. A large collaborative effort consistently failed to replicate a seminal demonstration of the facial feedback hypothesis, but meta-analysis suggests the effects are real. Consequently, we conducted a foundational test of the facial feedback hypothesis, wherein a large group of researchers specified the best way(s) to test the hypothesis and used this information to design and execute an international multi-lab experiment. Two pilot studies suggested that smiling could both magnify ongoing feelings of happiness and initiate feelings of happiness in otherwise non-emotional scenarios. Next, 18 labs from 17 countries will examine whether these findings can be replicated.