Socioemotional functioning in youth with borderline personality disorder

This thesis makes an original contribution to our understanding of socioemotional functioning in borderline personality disorder (BPD) by critically examining social cognition and emotion regulation BPD research from a developmental perspective. It also extends on previous research, making a novel and important contribution to our understanding of sociocognitive functioning and emotion regulation ability in youth with first presentation BPD. This was achieved via two critical narrative reviews of the existing literature and two empirical studies, which examined aspects of social cognition and emotion regulation considered key to interpersonal functioning in BPD. The empirical studies assessed, 1) unconscious simulation processes, a key aspect of affective empathy, and 2) the application of two emotion regulation strategies, expressive suppression and cognitive reappraisal, in the regulation of negative and positive affect, in a standard laboratory context, as well as in the context of social rejection. The reviews demonstrated that despite their shared diagnosis, important differences between young people and adults with BPD, in terms of their sociocognitive functioning and emotion regulation abilities, are evident. Future research and reviews should avoid conflating developmental age and stage of disorder. Instead, these processes, which are central to interpersonal functioning, need to be better understood over the course of BPD, especially early in its course. The empirical studies demonstrated that socioemotional functioning in youth with first presentation BPD is not uniformly affected. Specifically, rapid facial mimicry was unimpaired, contradicting predictions that heightened unconscious motor mimicry leads to heightened emotional contagion, and associated emotion regulation difficulties. Future research is needed to determine whether this finding also holds true for adults and young people later in the course of the disorder. Future research should also explore other factors that might lead to heightened emotional contagion and associated emotion regulation difficulties in BPD. Emotion regulation ability was largely preserved in youth with first presentation BPD, and functioning was mostly similar to that of typically developing young people. Specifically, for the most part, they could apply expressive suppression and cognitive reappraisal, to regulate both positive and negative affect (felt subjectively and expressed behaviourally), in a standard laboratory context and in the context of social rejection, with similar effectiveness to that of healthy youth. However, youth with first presentation BPD were not only unable to apply cognitive reappraisal to regulate the behavioural expression of negative emotions in the context of social rejection, but its application in this context intensified their facial expression of negative affect. They also demonstrated a pattern of pervasively blunted positive affect, relative to healthy youth, across indices and contexts. Further research is needed to better understand whether the effectiveness of cognitive reappraisal can be improved in this context, or whether it is contraindicated. Given that social rejection is commonly experienced by this group, and given the common application of cognitive strategies in therapy, future research is clearly needed to better understand the effectiveness and consequences of this, and alternative strategies, for use in the context of social rejection by youth with first presentation BPD. Finally, while positive affect has often been neglected in BPD research, the evident pervasive blunting clearly needs greater research and clinical attention in this group.