Imagery rescripting (ImRs): A model of the mechanisms of action and effectiveness factors in treatment for post-traumatic stress disorder (PTSD)

Abstract:
Post-traumatic stress disorder (PTSD) is characterised by the presence of intrusive and upsetting mental imagery of past traumatic events (American Psychiatric Association [APA], 2013). Research has begun to demonstrate the effectiveness of Imagery Rescripting (ImRs) (Arntz & Weertman, 1999; Smucker, Dancu, Foa, & Niederee, 1995) in the treatment of PTSD. However, despite this apparent effectiveness, there is currently a lack of research into the mechanisms of action underlying the technique and factors that moderate its effectiveness (Arntz, 2012). In addition, no qualitative studies have examined ImRs specifically. The aims of this study therefore were to explore individuals’ experience of ImRs in their treatment for PTSD, including factors that influenced its effectiveness, and consider potential mechanisms of action, relative to what is proposed by existing theory. Ten semi-structured interviews were conducted with participants from a London-based trauma service, who had experienced ImRs in their treatment for PTSD. The interviews were analysed using a Grounded Theory (GT) approach (Charmaz, 2014), which generated a theoretical model of ImRs. This model was based upon the nine theoretical codes and 34 focused codes that emerged from the data. The results suggested potential mechanisms of action to be change to memory representations, change to felt sense and change to metacognitive insight and self-efficacy. It was not possible to clearly determine the underlying memory change, however the majority of participants experienced a sense of two memories following ImRs, with some participants experiencing something closer to change to the original traumatic memory. Multiple effectiveness factors were evident, including the theoretical codes of ‘factors preceding ImRs’, ‘individual differences’, ‘the importance of the therapeutic structure’, ‘the importance of the therapist’, ‘creating an effective rescript’, ‘long-term accessibility of the rescript’ and ‘enhancing on-going use of ImRs’. The study’s strengths, limitations, clinical implications and suggestions for future research were also discussed.