Author: Jennifer Sun
Sun, Jennifer, 2023 Meta-awareness and posttraumatic stress disorder: An investigation of the characteristics and mechanisms of meta-awareness of trauma-related intrusions, Flinders University, College of Education, Psychology and Social Work
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Trauma-related intrusions are a key symptom type that is thought to lead to the development and maintenance of posttraumatic stress disorder (PTSD) (Ehlers & Clark, 2000). The typical method of assessment to index intrusion severity in both clinical practice and research is through trauma-exposed individuals self-reporting the frequency of intrusions. Nevertheless, recent studies have discovered that individuals are not always aware of their trauma-related mental content (labelled as meta-awareness failure; Nixon et al., 2021; Takarangi et al., 2014). Moreover, high- PTS individuals tend to experience more unaware intrusions, suggesting trauma-exposed individuals might underreport the actual frequency of intrusions (Nixon et al., 2021). Even though such phenomenon has been reported, the current literature lacks coherent information around characteristics and processes underpinning unaware intrusions, as our knowledge of PTSD intrusions has for the most part been based on studies where individuals were explicitly aware of their intrusion experience. For example, we know intrusions in these studies are vivid and accompanied with sensory impressions and strong emotion, but we have little idea whether this is the same for unaware intrusions. Hence, this thesis explored these issues, studying these and other characteristics and processes that might explain differences in the phenomenology of how such intrusions are experienced (e.g., alexithymia and maladaptive cognitive processes), whether these variables moderate the predicted effects of PTSD on meta-awareness, and whether a strategy commonly used by sufferers of PTSD (thought suppression) could cause changes in meta- awareness.
Study 1 examined the characteristics of aware and unaware intrusions by capturing the first intrusion that occurred while participants were reading scientific articles. Using a self-report questionnaire, the results show that aware and unaware intrusions shared similarities in terms of modality (imagery vs verbal thoughts), meaningfulness, accessibility, and other characteristics (e.g., distress). Study 2 aimed to replicate and extend Study 1, by using a meta-awareness task that captured multiple intrusions. Using a semi-structured interview, evidence showed that intrusions
accompanied by imagery, and which represented more meaningful aspects of the trauma to the individual were more likely result in meta-awareness, however aware and unaware intrusions were not different in terms of accessibility (i.e., ease of recall).
Study 3 investigated possible mechanisms underlying the PTSD–meta-awareness relationship by examining the moderation effect of alexithymia, trait rumination, state rumination, and thought suppression. Moreover, the study compared the effect of meta-awareness on those who experienced criterion A type trauma to those who experienced non-criterion A type trauma. The results showed that alexithymia and trait rumination did not moderate the proposed relationship. However, trauma-exposed individuals who ruminated on their trauma or suppressed their trauma- related thoughts were more likely to experience intrusion with meta-awareness. Moreover, all trauma-exposed individuals experienced unaware intrusions for events, even when such events did not constitute a criterion A trauma.
Study 4 sought to replicate the moderation results of Study 3, and to extend those findings by manipulating thought suppression to establish a causal relationship between thought suppression and meta-awareness. In addition, it was expected that the ability to be mindful and aware of one’s emotional and physical state (i.e., mindfulness) would be a moderator in the predicted causal relationship. However, there was no evidence that thought suppression caused changes in meta- awareness, although conclusions were tempered by less-than-optimal impact of the thought suppression manipulation. Mindfulness did not moderate the predicted relationship. However, the results replicated Study 3 findings in that alexithymia was not a moderator in the PTSD–meta- awareness relationship, but thought suppression did moderate the proposed relationship in a similar fashion as seen in Study 3. Nevertheless, trauma-specific rumination was not identified as a moderator. The theoretical and clinical implications of Studies 1-4 are further discussed in the concluding chapter.
Keywords: Meta-awareness, Meta-awareness Failure, Posttraumatic Stree Disorder, Trauma-related Memories, Trauma-related Thoughts, Intrusions, Avoidance, Alexithymia, Mindfulness, Rumination, PTSD
Subject: Psychology thesis
Thesis type: Doctor of Philosophy
Completed: 2023
School: College of Education, Psychology and Social Work
Supervisor: Professor Reg Nixon