Consistency of written trauma narratives over a course of trauma-focused therapy

Several of the procedures commonly used in trauma-focused therapies are similar to techniques that have been shown to influence the consistency and accuracy of memory in experimental settings. These techniques include verbalizing a non-verbal memory, repeatedly recalling an event, and recalling an event in the presence of another person. In an effort to examine the impact of these techniques on memory for a traumatic event, and in turn the impact of traumatic memory change on treatment outcome, the present study examined changes in the written trauma narratives created over the course of traumafocused therapy. Participants were PTSD positive female survivors of interpersonal assault (N = 41). Specific hypotheses predicted that participants who produced five written narratives would demonstrate greater increases in trauma-specific detail, more inconsistencies with respect to trauma details, and greater decreases in psychogenic amnesia than those participants who produced two written narratives. Results did not support these hypotheses and instead indicated that narrative length, amount of traumaspecific detail, and self-assessed ability to remember important aspects of the trauma did not change significantly from first to final narrative for either narrative condition. Although few factual inconsistencies were detected, qualitative analysis of the narratives revealed that many participants included important trauma-related details in the first account but not the final, or vice versa. Within the 5-narrative condition, narrative change was found to be predictive of PTSD symptom severity such that those participants who added more trauma details in the final narrative had more severe PTSD at post-treatment. Clinical and legal implications are discussed. Mott, Juliette, UMSL, 2010 p. 4 Consistency of Written Trauma Narratives Over a Course of Trauma-Focused Therapy A trauma is defined as an event in which an individual experiences or witnesses threat to the self or others, resulting in feelings of intense fear, helplessness, or horror (American Psychiatric Association, 2000). The way in which an individual processes the memory for this event has been theorized to be fundamental to the development and maintenance of Posttraumatic Stress Disorder (PTSD; Siegel, 1995; Harvey & Bryant, 1999), a disorder characterized by symptoms of avoidance, hyperarousal, and repeated reexperiencing of the traumatic event. The degree of disorganization of the traumatic memory may predict PTSD development (Gray & Lombardo, 2001; Halligan et al., 2003; Murray, Ehlers, & Mayou, 2002), and greater PTSD symptom severity appears to be related to inconsistencies in traumatic memory (Van Geizen et al., 2005). Traumatic memory also plays an important role in the treatment of PTSD, particularly with the exposure components included in empirically supported trauma interventions such as Cognitive Processing Therapy (CPT) and Prolonged Exposure (PE) which dedicate substantial time to the repetitive review of the traumatic memory. In these trauma-focused therapies, the clinician typically accepts a client’s self-reported memories of previous experiences as generally accurate. Good clinical care would be impeded if the therapist needed to question, verify, and confirm every aspect of a client’s self reported memories, and most professional guidelines regarding traumatic memory advise therapists to refrain from evaluating the veracity of a client’s memory (Health Council of the Netherlands, 2004). Assumptions of accuracy thus pervade, but little empirical or clinical attention has been given to potentially important changes in traumatic memory over the course of therapeutic treatment. This is particularly surprising Mott, Juliette, UMSL, 2010 p. 5 given the substantial body of research that has clearly established the limitations of autobiographical memory, and traumatic memory in particular (for a review see McNally, 2003). Traumatic Memories: Encoding, Storage, and Recall Few autobiographical memories are exact reproductions of the actual occurrence of any given event (McNally, 2003). Rather, these memories are subjected to a reconstructive process that can be influenced by the individual’s perspective and emotional arousal at the time of encoding. Encoding is the first of the three core processes of memory, preceding storage and retrieval, and involves the processing of sensory information into memory, either through automatic processing or conscious and effortful processing (Atkinson & Shiffrin, 1968). Traumatic memories are typically encoded when the individual is in a hyperaroused state, referred to as the “fight-or-flight” response. A number of physiological changes accompany this fear reaction, including elevated heart rate and blood flow away from the brain towards major muscle groups, often creating sensations of dizziness or lightheadedness. This physiological state and its associated emotions have been paradoxically linked with both increases and decreases in the clarity and accuracy of traumatic memory. On the one hand, some researchers suggest that a trauma victim’s intense emotions and extreme physiological response create a disadvantaged state for encoding memory (Christianson & Loftus, 1990; Halligan, Michael, Clark, & Ehlers, 2003), whereas others note that traumatic memories can often be intensely vivid and enduring (e.g., McGaugh, 2003; Peace, Porter, & ten Brinke, 2008). Although physiological and psychological arousal may increase memory clarity for some aspects of the trauma, this arousal appears to render other aspects of the Mott, Juliette, UMSL, 2010 p. 6 memory prone to error (Wessel & Merckelbach, 1994; Christianson, 1992; Van der Kolk & Fissler, 1995; Payne et al., 2006). Based on these equivocal findings, it appears that a conceptualization of extreme stress as singularly enhancing or detrimental to memory would be an overgeneralization, and would overlook the intricacies of the relationship between extreme stress and memory encoding. Once encoded, traumatic memories tend to be stored and retrieved differently then neutral memories. Traumatic memories tend to be stored as fragments, have little attached narrative, and are often dissociated from consciousness (Macintosh & Whiffen, 2005). Neuroimaging studies have provided evidence for the unique nature of traumatic memories, indicating that the recall of traumatic memories inspires activation patterns in the brain different than those inspired by everyday memories (Bremner, 2001). Specifically, neuropsychological evidence suggests decreases in hippocampal activity and increases in amygdala activity when recalling events of extreme stress (Jacobs & Nadel, 1998). Difficulty with traumatic memory retrieval has been linked with reduced perfusion (i.e., nutritive delivery of blood) in the right temporal and frontal areas of the brain, both of which are critical for episodic memory retrieval (Markowitsch et al., 1997). Trauma survivors commonly experience difficulty with memory retrieval, defined as the process of accessing stored memories, reporting that some important parts of the memory are missing or inaccessible. When an individual experiences memory loss for important aspects of a traumatic event, this is referred to as psychogenic amnesia. Psychogenic amnesia is considered to be a symptom of PTSD, and is defined in the DSM-IV (APA, 1994), as an “inability to remember important parts of the event. ” Although trauma induced dissociation can interfere with the ability to correctly encode a Mott, Juliette, UMSL, 2010 p. 7 memory of the traumatic event, psychogenic amnesia is typically conceptualized as the result of dysfunctions in storage and retrieval, rather than an encoding error (Kopelman, 2002). That is, victims can experience psychogenic amnesia for a traumatic experience that was fully encoded, but is not consciously available. Psychogenic amnesia for a traumatic event should also be distinguished from non-disclosure of the trauma, or conscious avoidance of thoughts related to the trauma, neither of which reflect an inability to recall the event, but rather, an unwillingness to revisit the horror of the experience (McNally, 2004). Clinically, many trauma victims report experiencing amnesia for an important aspect of the event that they could once recall, or feel that they could recall more of the trauma if they were to try harder to access that portion of the memory. This ‘feeling of knowing’ phenomenon provides support for the supposition of intact encoding. Moreover, additional details of an emotionally arousing event are often remembered at a later stage (Van Geizen et al., 2005), providing further evidence that the presence of psychogenic amnesia does not indicate a problem with encoding. In summary, although some trauma victims may remember certain aspects of the event with exceptional clarity, traumatic memories are by no means impervious to distortion. Although traumatic memories appear distinctive in terms of storage and recall, they appear to be as malleable as non-traumatic memories and equally, if not more so, susceptible to contamination and forgetting (Nourkova, Berstein, & Loftus, 2004). Prior claims by some (e.g., Goodman, 1991) that traumatic memories are by nature impervious to distortion have been challenged by empirical data. It is now generally accepted that traumatic memories are not immune to forgetting and distortion, and are, contrarily, Mott, Juliette, UMSL, 2010 p. 8 susceptible to errors and alterations during encoding, as well as the later stages of storage, and retrieval (Howe, 2000). Cognitive Research Trauma survivors who choose to participate in treatments that contain exposurebased components may be particularly vulnerable to changes in memory over time given that the therapeutic procedures and techniques used in these treatments demonstrate significant overlap with techniques that have been shown to influence memory in a laboratory