Investigating the link between intrusive memories and cognitive control

Abstract

Intrusive memories are memories for negative autobiographical events that come to mind without being deliberately recalled (Hackmann, Ehlers, Speckens, & Clark, 2004). Previous research has demonstrated that intrusive memories, and negative reactions to intrusive memories, are an important feature of depression (Starr & Moulds, 2006; Williams & Moulds, 2008b) and contribute to the maintenance of depression longitudinally (Newby & Moulds, 2011c). It has also been established that intrusive memory experience is related to individual differences in cognitive control, specifically in proactive interference resolution (Verwoerd, Wessel, & de Jong, 2009; Verwoerd, Wessel, de Jong, Nieuwenhuis, & Huntjens, 2011). The present thesis aimed to extend upon these existing findings, using the Dual Mechanism of Control theory, which distinguishes between proactive and reactive modes of control (Braver, Gray, & Burgess, 2007). Furthermore, in view of some recent ambiguity of the defining feature of an intrusive memory, as compared to a negative involuntary memory more generally (Kvavilashvili, 2014; Moulds & Krans, 2015), another goal of the thesis was to incorporate a wider focus of involuntary memories, rather than focusing only on traditionally studied intrusive memories. Participants from the student population and local community were tested. Overall, results provide some evidence for a negative involuntary memory related deficit in proactive control, on both a classic and an emotional version of the AX-Continuous Performance Task (AX-CPT). Conversely, there was no link between intrusive or involuntary memory experience and reactive control. A brief mindfulness and self-compassion based intervention, designed to reduce negative reactions to intrusive memories, was also tested. The intervention was successful in reducing intrusive-memory distress, and recommendations for the future development of the intervention are presented.