Your Face and Moves Seem Happier When I Smile Facial Action Influences the Perception of Emotional Faces and Biological Motion Stimuli

In this experiment, we replicated the effect of muscle engagement on perception such that the recognition of another's facial expressions was biased by the observer's facial muscular activity (Blaesi & Wilson, 2010). We extended this replication to show that such a modulatory effect is also observed for the recognition of dynamic bodily expressions. Via a multitab and within-subjects approach, we investigated the emotion recognition of point-tight biological walkers, along with that of morphed face stimuli, white subjects were or were not holding a pen in their teeth. Under the "pen-in-the-teeth" condition, participants tended to tower their threshold of perception of happy expressions in facial stimuli compared to the "no-pen" condition, thus replicating the experiment by Blaesi and Wilson (2010). A similar effect was found for the biological motion stimuli such that participants Lowered their threshold to perceive happy walkers in the pen-in-the-teeth condition compared to the no-pen condition. This pattern of results was also found in a second experiment in which the no-pen condition was replaced by a situation in which participants held a pen in their lips ("pen-in-tips" condition). These results suggested that facial muscular activity alters the recognition of not only facial expressions but also bodily expressions.