Current theories of PTSD propose that impaired retrieval of trauma memories may impede processing of these memories and subsequent trauma recovery. This thesis investigated memory retrieval processes in trauma survivors with and without symptoms of posttraumatic stress, and in non-traumatised individuals exposed to a highly arousing event. Study 1 examined deliberate avoidance of unwanted memories in recent trauma survivors. The results indicated that attempts to forget were associated with poorer recall of forgotten information, but the size of this effect did not depend on the presence or absence of Acute Stress Disorder (ASD). Study 2 investigated automatic retrieval inhibition in trauma survivors with or without Posttraumatic Stress Disorder (PTSD). The results suggested that repeated retrieval of trauma-related information by individuals with PTSD can cause inhibition of related, but unpractised information. Studies 3 and 4 examined the relationship between the vantage point of trauma memories, avoidance and posttraumatic stress symptomatology. The findings indicated that recalling a traumatic event from an observer perspective is associated with post trauma avoidance. They also showed that an observer vantage point in the initial few weeks after trauma is associated with poorer long-term post trauma adjustment. Studies 5, 6 and 7 were analogue studies which analysed the impact of heightened arousal on memory retrieval in novice skydivers. The results suggested that elevated arousal can interfere with retrieval of information related to the arousal-inducing event. Study 7 also indicated that autobiographical memory for the event may be impaired. Finally, Study 8 examined the qualities of trauma memories that were accessed via different modes of retrieval. The results provided evidence that intrusive memories were experienced as more realistic and with more intense affect than memories for the same event that were deliberately retrieved. Together, the findings of this program of research extend current theories of PTSD by highlighting the mechanisms through which retrieval of trauma memories may be impaired. The results suggest that the quality of trauma memories is affected by avoidance processes, elevated arousal and level of conscious control the individual exerts over retrieval.

Current theories of PTSD propose that impaired retrieval of trauma memories may impede processing of these memories and subsequent trauma recovery. This thesis investigated memory retrieval processes in trauma survivors with and without symptoms of posttraumatic stress, and in non-traumatised individuals exposed to a highly arousing event. Study 1 examined deliberate avoidance of unwanted memories in recent trauma survivors. The results indicated that attempts to forget were associated with poorer recall of forgotten information, but the size of this effect did not depend on the presence or absence of Acute Stress Disorder (ASD). Study 2 investigated automatic retrieval inhibition in trauma survivors with or without Posttraumatic Stress Disorder (PTSD). The results suggested that repeated retrieval of trauma-related information by individuals with PTSD can cause inhibition of related, but unpractised information. Studies 3 and 4 examined the relationship between the vantage point of trauma memories, avoidance and posttraumatic stress symptomatology. The findings indicated that recalling a traumatic event from an observer perspective is associated with post trauma avoidance. They also showed that an observer vantage point in the initial few weeks after trauma is associated with poorer long-term post trauma adjustment. Studies 5, 6 and 7 were analogue studies which analysed the impact of heightened arousal on memory retrieval in novice skydivers. The results suggested that elevated arousal can interfere with retrieval of information related to the arousal-inducing event. Study 7 also indicated that autobiographical memory for the event may be impaired. Finally, Study 8 examined the qualities of trauma memories that were accessed via different modes of retrieval. The results provided evidence that intrusive memories were experienced as more realistic and with more intense affect than memories for the same event that were deliberately retrieved. Together, the findings of this program of research extend current theories of PTSD by highlighting the mechanisms through which retrieval of trauma memories may be impaired. The results suggest that the quality of trauma memories is affected by avoidance processes, elevated arousal and level of conscious control the individual exerts over retrieval.

Current theories of PTSD propose that impaired retrieval of trauma memories may impede processing of these memories and subsequent trauma recovery. This thesis investigated memory retrieval processes in trauma survivors with and without symptoms of posttraumatic stress, and in non-traumatised individuals exposed to a highly arousing event. Study 1 examined deliberate avoidance of unwanted memories in recent trauma survivors. The results indicated that attempts to forget were associated with poorer recall of forgotten information, but the size of this effect did not depend on the presence or absence of Acute Stress Disorder (ASD). Study 2 investigated automatic retrieval inhibition in trauma survivors with or without Posttraumatic Stress Disorder (PTSD). The results suggested that repeated retrieval of trauma-related information by individuals with PTSD can cause inhibition of related, but unpractised information. Studies 3 and 4 examined the relationship between the vantage point of trauma memories, avoidance and posttraumatic stress symptomatology. The findings indicated that recalling a traumatic event from an observer perspective is associated with post trauma avoidance. They also showed that an observer vantage point in the initial few weeks after trauma is associated with poorer long-term post trauma adjustment. Studies 5, 6 and 7 were analogue studies which analysed the impact of heightened arousal on memory retrieval in novice skydivers. The results suggested that elevated arousal can interfere with retrieval of information related to the arousal-inducing event. Study 7 also indicated that autobiographical memory for the event may be impaired. Finally, Study 8 examined the qualities of trauma memories that were accessed via different modes of retrieval. The results provided evidence that intrusive memories were experienced as more realistic and with more intense affect than memories for the same event that were deliberately retrieved. Together, the findings of this program of research extend current theories of PTSD by highlighting the mechanisms through which retrieval of trauma memories may be impaired. The results suggest that the quality of trauma memories is affected by avoidance processes, elevated arousal and level of conscious control the individual exerts over retrieval.

Doctor of Clinical Psychology/ Master of Science (DCP/ MSc) / A number of international studies reveal high prevalence rates of posttraumatic stress disorder (PTSD) within homeless populations. Recent research on PTSD indicates that cognitive responses to trauma are critical in determining who develops the disorder. In Australia, a number of studies indicate exceptionally high rates of trauma experience among homeless adults, yet PTSD has not been investigated in this cohort. Therefore, the primary aim of this project was to improve understanding of PTSD and related cognitions in a sample of homeless adults in Sydney. The project attempts to determine the prevalence of PTSD and its onset in relation to homelessness (Study One) and also explores the role of cognitions in PTSD (Study Two). The sample consisted of seventy homeless men and women aged 18 to 73 years, who were randomly sampled through eight homeless services. A computer-assisted face-to-face structured clinical interview was conducted for each participant. The majority of the sample stated that they had experienced at least one traumatic event in their lifetime (98.2%). The twelve-month prevalence of PTSD was higher among homeless adults in Sydney in comparison to the Australian general population (41.1% versus 1.5%). In 59.1% of cases, the onset of PTSD was found to have occurred before the age of the first reported homeless episode. In a comparison of those with and without a current diagnosis of PTSD, it was found that those with PTSD scored significantly higher overall on measures of posttraumatic cognitions and early maladaptive schemas. In particular, this group scored higher on schemas that centre on the world being entirely dangerous and the self being totally inept. A mediational analysis showed that when trauma and mental health care were controlled, the relationship between early maladaptive schemas and PTSD symptom severity was mediated by posttraumatic cognitions. It was concluded that homeless adults in Sydney frequently experience trauma and PTSD, which typically precedes homelessness. It was also concluded that among homeless adults, posttraumatic cognitions and early maladaptive schemas appear to play an important role in PTSD and may be associated with symptom severity. These findings have implications for public policy on homelessness and mental health, homeless service provision, PTSD theory, and PTSD treatment for homeless adults.

Thesis (Psy.D.)--California School of Professional Psychology, 1998. / Includes bibliographical references.

Thesis (M.Psych.(Clin.)) -- University of Adelaide, Dept. of Psychology, 2005? / Bibliography: leaves 43-46.

Thesis (Ph.D.)--Murdoch University, 2006. / Thesis submitted to the Division of Health Sciences. Bibliography: leaves 176-207.

Thesis (M.A.)--Cleveland State University, 2008. / Abstract. Title from PDF t.p. (viewed on Mar. 17, 2009). Includes bibliographical references (p.37-42) and appendices. Available online via the OhioLINK ETD Center. Also availabe in print.

Thesis (M. S. in Psychology)--Vanderbilt University, May 2009. / Title from title screen. Includes bibliographical references.

Thesis (D. Min.)--Ashland Theological Seminary, 2007. / Abstract. Includes bibliographical references (leaves 233-248).