A meta-analysis of the facial feedback literature: Effects of facial feedback on emotional experience are small and variable.

The facial feedback hypothesis suggests that an individual's experience of emotion is influenced by feedback from their facial movements. To evaluate the cumulative evidence for this hypothesis, we conducted a meta-analysis on 286 effect sizes derived from 138 studies that manipulated facial feedback and collected emotion self-reports. Using random effects meta-regression with robust variance estimates, we found that the overall effect of facial feedback was significant but small. Results also indicated that feedback effects are stronger in some circumstances than others. We examined 12 potential moderators, and 3 were associated with differences in effect sizes: (a) Type of emotional outcome: Facial feedback influenced emotional experience (e.g., reported amusement) and, to a greater degree, affective judgments of a stimulus (e.g., the objective funniness of a cartoon). Three publication bias detection methods did not reveal evidence of publication bias in studies examining the effects of facial feedback on emotional experience, but all 3 methods revealed evidence of publication bias in studies examining affective judgments. (b) Presence of emotional stimuli: Facial feedback effects on emotional experience were larger in the absence of emotionally evocative stimuli (e.g., cartoons). (c) Type of stimuli: When participants were presented with emotionally evocative stimuli, facial feedback effects were larger in the presence of some types of stimuli (e.g., emotional sentences) than others (e.g., pictures). The available evidence supports the facial feedback hypothesis' central claim that facial feedback influences emotional experience, although these effects tend to be small and heterogeneous. (PsycINFO Database Record (c) 2019 APA, all rights reserved).