Abstract
INTRODUCTION: Individuals with borderline personality disorder (BPD) are thought to experience specific biosocial vulnerabilities that give rise to a maladaptive negativity bias in the perception and expression of emotions. However, while this negative bias has been identified in adults with full threshold BPD or high BPD features, it is unclear whether it is evident earlier in the course of the disorder - that being, young persons with first-presentation BPD meeting three or more BPD features, as defined by early intervention models. METHODS: The current study compared patterns of facial responding in individuals aged 15-25 years first presenting to a specialist outpatient service with three or more BPD features (n = 32) to age-matched healthy controls (n = 46). Facial electromyography was used to assess muscle activity associated with positive (zygomaticus major) and negative (corrugator supercilii) expression while participants viewed happy, angry, and neutral facial expressions. RESULTS: The data revealed that negative facial emotional reactivity for the BPD group did not significantly differ from the control group. However, the results for positive emotional reactivity were more nuanced, indicating that while there was not an overall between-group difference, there might be an effect of time suggestive of a slower positive emotional reaction to happy faces by the BPD group. CONCLUSIONS: These data provide initial evidence that negatively biased emotional expression, when responding with negative facial expressions to neutral, happy, or angry faces, is not evident in young persons first presenting to a specialist outpatient service for treatment of BPD. However, a bias may be demonstrated by what appears to be a slower positive affective response to happy faces. The implications of these findings are discussed, particularly in relation to factors associated with chronicity of illness that might potentially contribute to the development of a more pronounced negativity bias later in the course of the illness. We encourage further examination of negativity biases in the developmental sequelae of BPD via longitudinal design or cross-sectional designs that include BPD participants across the course of illness, as well as further research to explore the possibility that positive affective reactions in this group might not be grossly blunted but rather delayed.