Is Splitting Related to Resistance to Proactive Interference? A Process-Oriented Study of Kernberg's Conceptualization of Splitting

INTRODUCTION: Splitting, as a defense mechanism in Kernberg's theory, plays a significant role in the development and maintenance of polarized and oscillating representations of self/other characteristics of borderline personality disorder (BPD). Although the notion of splitting can be considered from a structural and a functional point of view, almost all empirical studies to date have focused on the former elements to the detriment of related cognitive processes. METHODS: To further investigate the cognitive processes related to splitting, 60 participants were administered the Splitting Index and indexes of resistance to proactive interference (PI) using the interpersonal recent negative task with words that reflect negative or positive interactions compared to neutral words. RESULTS: The use of splitting was uniquely and significantly predicted by a higher capacity to resist PI and a lower capacity to consistently maintain this resistance when presented with negative words, above and beyond BPD traits, primitive defenses, and the presentation of neutral words. Results showed no evidence of a relationship between splitting and resistance to PI with positive words. CONCLUSION: Results appear compatible with Kernberg's conceptualization of splitting as an active defense process that relates to an unstable capacity to inhibit negative representations of the object from entering working memory.