توسعه نفوذ کاهش یافته پس از اسکریپت نویسی تصویرسازی مجدد پساتروما . یک مطالعه تجربی

Background and objectives Contemporary theories predict PTSD development after trauma if trauma information is not adequately processed or negatively appraised. Mental imagery and emotional processing seem to be strongly related and evidence-based treatment strategies such as imaginal exposure and EMDR indeed include imagery as a main component. Moreover, imagery rescripting of traumatic memories is an effective treatment for PTSD. Methods The present study combined these lines of research and investigated the impact of early imagery rescripting on intrusion development after an aversive film. Seventy-six participants were randomly allocated to one of three conditions: imagery rescripting (IRS), imagery reexperiencing (IRE) and positive imagery (PI). All participants watched an aversive film, had a 30-min break and then received a 9-min intervention (IRS, IRE or PI). They indicated subjective distress during the intervention, recorded intrusive memories of the film for 1 week and completed the Posttraumatic Cognitions Inventory (PTCI) and a cued recall test one week later. Results The IRS group developed fewer intrusive memories relative to the IRE and PI groups, and less negative cognitions than the IRE group, while cued recall was enhanced in IRS and IRE groups compared to the PI group. IRS and PI groups experienced less distress during the intervention than the IRE group. Limitations This is an analogue design and results should be replicated in clinical samples. Conclusions The results suggest that IRS might be an adequate technique to change memory consolidation at an early stage and therefore a powerful and non-distressing strategy to prevent PTSD symptoms.

Contemporary theories posit that at least part of the reason for someone to develop posttraumatic stress disorder (PTSD) after trauma lies in the fact that information is not adequately processed during and after trauma (Brewin, 2001, Brewin et al., 1996 and Ehlers and Clark, 2000). In other words, early information processing (i.e., encoding of trauma information) and the formation of an “inadequate trauma memory” (or “fear structure”; Foa and Kozak, 1986 and Foa et al., 1989) play a key role in the development of vivid reexperiences. Experimental studies indeed showed that factors affecting the encoding of trauma-related information, such as tonic immobility (Hagenaars, Van Minnen, Holmes, Brewin, & Hoogduin, 2008), visuospatial tasks (Holmes, Brewin, & Hennessy, 2004), or dissociation (Kindt, Van den Hout, & Buck, 2005) affected the development of intrusions. Moreover, clinical studies also found some of these peritraumatic factors, like tonic immobility (Heidt, Marx, & Forsyth, 2005) and dissociation (Ehlers, Mayou, & Bryant, 1998) to be related to subsequent PTSD development. Treatments may be seen as reversing this process. That is, treatments that focus on changing the PTSD trauma memory structure prove successful in reducing PTSD symptoms, as is the case in imaginal exposure and EMDR treatments (e.g., Bradley, Green, Russ, Dutra, & Westen, 2005). Recently, a new technique called imagery rescripting was introduced. When combined with imaginal exposure, imagery rescripting proved as effective as imaginal exposure alone in changing PTSD symptoms, with fewer patients dropping out of treatment. Moreover, relative to pure imaginal exposure, patients also showed a greater decrease in anger, guilt and shame if imagery rescripting was added (Arntz, Tiesema, & Kindt, 2007). Imagery rescripting was also effective as treatment for snake phobia (Hunt & Fenton, 2007), intrusive memories in depression (Brewin et al., 2009), and personality disorders (Weertman & Arntz, 2007). In imagery rescripting, participants imagine different responses to and outcomes of the original event and its aftermath. A new script might include somebody else entering the scene and bringing safety, or the participant being in power and preventing the trauma, or taking revenge on perpetrators. Part of its effects might be explained by the healthy effects of expressing inhibited responses, and part by the adaptive effects of the change of meaning of the original event (Arntz, 2011, Arntz and Weertman, 1999 and Arntz et al., 2007). In classical conditioning terms, imagery rescripting changes the UCS-UCR representation in memory by imagining more functional responses and outcomes to the original event. This so-called UCS/UCR revaluation changes the meaning of the fear memory underlying trauma-related symptoms (Arntz, 2011 and Davey, 1989). By using imagery, the meaning change not only takes place on a verbal cognitive level, but also on sensory, emotional and behavioural levels. By affecting imagery-based processing directly, imagery rescripting may not only serve treatment goals, but could also be an adequate tool in preventing the trauma-related, intrusive images from developing in the first place. There is some research suggesting the powerful effect of imagery on future behaviour and affect. For example, the ease of imagining the symptoms of a disease was associated with subsequent likelihood ratings of contracting that disease (Sherman, Cialdini, Schwartzman, & Reynolds, 1985). Interesting, similar findings were found with respect to positive affect. That is, participants imagining positive events reported greater increases in positive affect than participants thinking about the verbal meaning of that event. The former group also rated new descriptions as more positive than the latter (Holmes, Mathews, Dalgleish, & Mackintosh, 2006). Imagery can also alter judgements about past events (e.g., Garry, Manning, Loftus, & Sherman, 1996), again suggesting the relevance with respect to trauma and PTSD prevention. Thus far, early post-trauma PTSD prevention strategies, like psychological debriefing, are often ineffective or even harmful (Wessely & Deahl, 2003). Early intervention may be a better strategy, although results with a brief cognitive therapy for persons with acute PTSD were not very promising in preventing chronic PTSD (Sijbrandij et al., 2007). Cognitive behavioural strategies were effective in acute stress disorder (e.g., Bryant et al., 2003 and Bryant et al., 2005), but acute stress disorder is not necessarily predictive of PTSD (Bryant, Creamer, O’Donnell, Silove, & McFarlane, 2008). The early interventions that have been investigated thus far mainly focus on exposure to traumatic memories and/or cognitive restructuring. Imagery rescripting may be a fruitful alternative. Besides the strong association between imagery and affective processing (Hagenaars, Brewin, Van Minnen, Holmes, & Hoogduin, 2010), the rescripting part may lead to altered encoding and consolidation of trauma information (e.g., feelings of mastery associated with the new script become linked to the trauma information). This may result in the development of other sorts of memories in the first place and therefore lead to more positive affect and (trauma-related) cognitions. In the present study manipulations were done 30 min after analogue trauma for this reason. That is, memory consolidation is still in progress at that point (Dudai, 2004), meaning that the memory is still labile and sensitive to change. Also, practically, as our manipulations were new, we wanted to keep their timing in accordance with previous experimental studies that found effects of manipulations conducted 30 min post-stressor on the development of intrusive memories (Holmes et al., 2009 and Holmes et al., 2010). The present study explores whether imagery rescripting affects intrusion development using an experimental trauma film paradigm. Participants were randomized over three post-film conditions: imagery rescripting (IRS), imagery reexperiencing (IRE) and positive imagery (PI).

Two participants were identified as univariate outliers with more than 3 standard deviations above the mean. Their scores were changed into a score that was one unit higher next most extreme score in the distribution, so that the between-subject order remained the same (Tabachnick & Fidell, 1996). Effect sizes (Cohen’s d and partial η2) are reported for all outcomes. Paired samples t-tests yielded significant pre-film to post-film increases in anxiety, horror, sadness, and anger (all t(75) < - 5.08, all ps < .001), with a main increase in horror (from .46 pre-film to 5.75 post-film) indicating the film was quite horrifying. A 2 (Time) × 3 (Condition) repeated measures analysis of variance (ANOVA) showed no Time x Condition effect (F(2, 73) < .83 and p > .44 for all emotions) demonstrating that there were no differences between conditions in emotional impact of the film.