Humans have the most complex facial muscles of any animal, allowing for a wide range of diverse facial expressions. A recent study found that dynamic facial expressions during social interactions affect how others perceive us and determine our success in these interactions.

Researchers conducted video calls with 52 participants to record their natural reactions and expressions during various scenarios. More than 170 people then rated these videos to assess the participants' readability and likeability. The researchers then analyzed unscripted video conversations between more than 1,400 strangers, comparing likeability ratings with Facial Action Coding Scheme measures.

They found that participants exhibited considerable variation in facial expressivity but varied little across different contexts, social partners, or over time. Participants who were more facially expressive were generally more well-liked, found to be more pleasant, and were more successful in negotiations, especially if they were also agreeable. The participants' abilities to convey emotions through facial expressions and the readability of these expressions were both linked to likability.

These findings suggest that being expressive with facial expressions provides social advantages, as people who show more facial expressiveness tend to be better liked and are seen as more agreeable and competent. Interestingly, other research has shown that Botox injections, which inhibit facial expressions, may impair a person’s interpretation of facial expressions. When people who had Botox injections viewed emotional facial expressions, they exhibited altered activity in their amygdala—an area of the brain involved in processing fearful and threatening stimuli.

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