Emotional switching in borderline personality disorder: A daily life study.

Despite large efforts to understand emotional instability in borderline personality disorder (BPD), it is still unclear exactly how this is manifested in the daily lives of people suffering from the disorder. Building on theoretical and clinical observations of BPD, we propose that the emotional instability in BPD particularly consists of the occurrence of strong changes between positive and negative emotional states from 1 moment to the next, labeled emotional switching. We tested this proposal by means of an experience sampling study in which 30 BPD patients and 28 healthy controls reported in their daily lives the level of pleasantness/unpleasantness of their emotional states 10 times a day for 8 consecutive days using handheld palmtops. Results showed that although BPD patients did not differ from healthy controls regarding their overall tendency to switch from a positive to a negative emotional state or vice versa, the size of such changes between positive and negative states was found to be significantly larger in BPD patients. In contrast, the magnitude of emotional changes that remained within the negative emotional range or positive emotional range was not particularly larger for BPD patients compared with healthy participants. These findings imply that the emotional instability in BPD is particularly characterized by larger changes from positive to negative states and vice versa, rather than overall larger changes in intensity, providing insight into possible processes underlying emotion dysfunction in BPD.