A multi-lab test of the facial feedback hypothesis by the Many Smiles Collaboration

Following theories of emotional embodiment, the facial feedback hypothesis suggests that individuals' subjective experiences of emotion are influenced by their facial expressions. However, evidence for this hypothesis has been mixed. We thus formed a global adversarial collaboration and carried out a preregistered, multicentre study designed to specify and test the conditions that should most reliably produce facial feedback effects. Data from n = 3,878 participants spanning 19 countries indicated that a facial mimicry and voluntary facial action task could both amplify and initiate feelings of happiness. However, evidence of facial feedback effects was less conclusive when facial feedback was manipulated unobtrusively via a pen-in-mouth task.
National Science Centre, Poland [2019/35/B/HS6/00528]; JSPS KAKENHI [16H03079, 17H00875, 18K12015, 20H04581, 21H03784]; National Council for Scientific and Technological Development (CNPq); Polish National Science Center; DFG Beethoven grant [2016/23/G/HS6/01775]; National Science Foundation Graduate Research Fellowship [R010138018]; Ministerio de Ciencia, Innovacion y Universidades [PGC2018-098558-B-I00]; Comunidad de Madrid [H2019/HUM-5705]; Teesside University; Occidental College Academic Student Project Award
This work was financially supported by B. Stastny, who generously donated funds for this research in memory of his father, Bill Stastny (J.T.L.). The work was also supported by the National Science Centre, Poland (grant no. 2019/35/B/HS6/00528; K.B.), JSPS KAKENHI (grant nos 16H03079, 17H00875, 18K12015, 20H04581 and 21H03784; Y.Y.), the National Council for Scientific and Technological Development (CNPq; R.M.K.F.), the Polish National Science Center (M.P.), the DFG Beethoven grant no. 2016/23/G/HS6/01775 (M.P.), the National Science Foundation Graduate Research Fellowship (grant no. R010138018; N.A.C.), the Ministerio de Ciencia, Innovacion y Universidades (grant no. PGC2018-098558-B-I00; J.A.H.), the Comunidad de Madrid (grant no. H2019/HUM-5705; J.A.H.), Teesside University (N.B.) and the Occidental College Academic Student Project Award (S.L.). The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. We also thank C. Scavo and A. Bidani for help with translating the study materials, L. Pullano and R. Giorgini for help with coding, and E. Tolomeo and L. Pane for help with data collection.