Rapid facial mimicry responses are preserved in youth with first presentation borderline personality disorder

Background
Empathy is a complex and multifaceted construct comprising cognitive and affective components. Abnormal empathic responses are implicated in borderline personality disorder (BPD). Specifically, unconscious motor mimicry (a primitive component of affective empathy evident from infancy) is theorized to be heightened and to contribute to the heightened emotional contagion often seen in people with BPD. Yet, no study has directly tested whether abnormally heightened unconscious motor mimicry is associated with BPD features or whether this is present early in the course of BPD.

Methods
In the present study, facial electromyography was used to assess the rapid facial mimicry responses (a form of unconscious motor mimetic responding) of 32 outpatient youths (aged 15–25 years) with early stage BPD features and 47 demographically matched healthy control participants (HC).

Results
The results showed no group differences in rapid facial mimetic responses to either positive (happy) or negative (angry) facial emotions.

Limitations
Co-occurring psychopathology and the potential impact of state affect on rapid facial mimicry were considered and discussed.

Conclusions
These data indicate that there is no evidence for abnormally heightened rapid motor mimicry in youth early in the course of BPD, suggesting that rapid facial mimicry is preserved in this group. It is thus unlikely that abnormally heightened unconscious simulation contributes to heightened emotional contagion in youth with first presentation BPD. Future research should explore alternative mechanisms for this phenomenon and also whether abnormalities in motor mimetic responses are evident in later stages of the disorder.