A randomised multiple baseline case series of a novel imagery rescripting protocol for intrusive trauma memories in people with psychosis.

ABSTRACT

BACKGROUND AND OBJECTIVES: There has been limited investigation of therapies targeting trauma-related psychological mechanisms hypothesised to play a role in post-traumatic and psychosis symptoms. Imagery rescripting (ImRs) is a therapeutic technique which involves transforming images, such as episodic memories, to modify associated distressing beliefs. This study is the first ImRs study for psychosis to incorporate experimental controls. We used a novel ImRs protocol, targeting present-focused, self-referential distressing meanings associated with intrusive trauma memories. A multiple baseline case series design investigated whether the protocol was feasible, safe, acceptable and effective. METHODS: 12 participants with a psychosis diagnosis and intrusive trauma memories were assessed and randomised to a monitoring period (one, two or three weeks), followed by three ImRs sessions (over three weeks), a further two-week monitoring period with a post-therapy assessment a week after completing therapy. Memory phenomenology was assessed daily during monitoring. Post-traumatic stress symptoms and wellbeing were assessed pre and post therapy. RESULTS: ImRs was feasible, safe and rated as highly acceptable. No participants dropped-out of the brief, targeted intervention. There were moderate effects on the frequency, distress, controllability and appraisals of trauma memories. Notably, ten participants showed reliable change, and seven clinically significant change, in post-traumatic stress symptoms. LIMITATIONS: Assessments were not blinded and impact on psychosis was not examined. CONCLUSIONS: The study indicates that a brief, novel ImRs protocol targeting present-focused, self-referential meanings is a promising intervention for intrusive trauma memories. Future research should investigate its integration into trauma-focused therapy for psychosis and impact on psychosis severity.