No evidence for modulation of facial mimicry by attachment tendencies in adulthood: an EMG investigation.

Mimicking another individual functions as a social glue: it smoothens the interaction and fosters affiliation. Here, we investigated whether the intrinsic motivation to affiliate with others, stemming from attachment relationships, modulates individuals' engagement in facial mimicry (FM). Participants (N = 100;  = 24.54 years,  = 3.90 years) observed faces with happy, sad, and neutral expressions, while their facial muscle activity was recorded with electromyography. Attachment was measured with the Attachment Styles Questionnaire, which provides a multidimensional profile for preoccupied and dismissing styles. It was proposed that the preoccupied and dismissing styles are characterized by high and low intrinsic affiliation motivation, respectively, and these were hypothesized to manifest in enhanced and diminished FM. Participants showed happy and sad FM, yet attachment styles did not significantly predict FM. Bayes Factor analyses lend evidence favoring the null hypothesis, suggesting that adult attachment do not contribute to FM.