What is the facial feedback hypothesis and what is known about it?

Psychologists thought that exercises such as holding a pen between your teeth could make someone happier. This was based on ‘facial feedback hypothesis’: the idea that emotional expressions like smiling could make the brain actually happier. However, scientists that have looked more into this have found that the theory behind this facial feedback is not complete.

In 1872, Darwin already thought about that smiling could make someone happier. For example, he wondered whether emotions that are expressed are felt more intensely compared to emotions that are repressed. In 1988, social psychologist Fritz Strack published a study on facial feedback, and found that participants who held a pen between their teeth rated comic news papers as more funnier than a control group. There was a lot of support for the facial feedback hypothesis.

In 2016, there was a turnaround when 17 labs failed to replicate the ‘pen study’. These studies were good studies, because they repeated the original study by Strack as closely as possible. This was devastating for the emotion literature, because a lot of this literature was based on the facial feedback theory! This is just part of the ‘replication crisis’. Wagenmakers suggest that the failure to replicate signals the need for more studies and other questions.

The Many Smiles Collaboration is based on the pen study from 1988. It is based on intense collaboration, peer reviewers and journal editors. The goal of this collaboration is to find out more about the facial feedback hypothesis and answer: does smiling really make you happier? An early pilot study indicated that the hypothesis might be true: smiling does seem to affect happiness. However, there will be more research needed on this topic before any conclusions can be made!