Although it is well established that persons with traumatic brain injury (TBI) experience word retrieval difficulties, the underlying cause of these deficits is not known. Difficulties with word retrieval have negative social implications as they can impact on the ability to converse with others. The overarching goal of this dissertation was to determine the underlying cause of problems with word retrieval after TBI. To test word retrieval in this dissertation, participants were given a series of word fluency tasks and the speed of word generation was measured. In addition to measuring interresponse times, procedures used by Rohrer, Wixted, Salmon and Butters (1995) were also followed. This involved the calculation of parameter estimates to investigate whether slowed retrieval or degraded semantic stores were responsible for the patients� word retrieval difficulties. One parameter (N) was a measure of the total number of retrievable words and the second parameter (tau) was an estimate of mean latency. Study 1 was designed to trial the procedure and equipment adopted throughout this dissertation to analyse speech. University students were presented with categories on a computer screen and asked to generate as many exemplars as possible in 60 seconds. A PowerLab Chart sound system was used to measure the time that each word was generated. The results of Study 1 showed that the methodology of previous research could be replicated using the PowerLab Chart sound system. In Study 2, persons with postconcussion syndrome (PCS) and matched controls were given two word fluency tasks. Results showed that on both tasks patients recalled fewer words, had longer pauses between words, and took significantly longer to generate their first word than controls. Also, patients had a significantly reduced N relative to controls, but there was no difference in tau between patients and controls. Given that the participants had not finished responding and that parameter estimates require responses to be exhausted, Study 3 was designed to replicate the findings of Study 2 using an extended recall period. In Study 3, patients with PCS and matched controls completed a series of word fluency tasks and were given extended periods of time to generate words. Results showed that the patients obtained significantly fewer words on two of the tasks, but no evidence of slowed retrieval was found. There was also no difference in the estimates of N and tau between patients and controls. As the patients in Study 3 sustained more minor injuries than those in Study 2, Study 4 tested patients with severe TBI. In Study 4, patients with severe TBI and matched controls were given a series of word fluency tasks. Results showed that the patients generated fewer words and experienced slowed retrieval. Again, there was no difference in the estimates of N and tau between patients and controls. The results of Study 4 confirmed the hypothesis that slowed word retrieval is a consequence of TBI. Taken together, the results of this dissertation show that an underlying slowness of processing is the primary cause of problems with word retrieval in persons with TBI.

Environmental factors such as stress and hormones acting during embryogenesis, as well as early life experiences such as parental care have been clearly demonstrated in animal models to shape the individual's phenotypic gene expression, brain development, and behavioural repertoires ( Meaney, 2005 ). However, human studies have not assessed both prenatal mental health and the quality of postnatal parental care with the same sample of mothers. The current study sought to fill this gap by investigating the impact of women's experiences of trauma and posttraumatic stress disorder ( PTSD ) before pregnancy on the mother's ante - and postnatal mental health problems, parenting, and children developmental outcomes. The study reported here is the second phase of a longitudinal study that commenced in 2002. In phase one community based middle class women in their third trimester of pregnancy were recruited and followed during the early postnatal period ( Linke, 2002 ; Lowe 2003 ). The current study assessed forty four mother - infant dyads at three time points during the second postnatal year. The dyads were divided into one of three groups ( control, trauma control and PTSD ) depending on the mother's trauma experience and whether she met the lifetime diagnosis for PTSD. The assessments included the measure of the mother and infant's basal cortisol, the mother's lifetime and ongoing mental health problems, the quality of the mother - infant relationship, and the development of the infant's general cognitive abilities, emerging language skills and emotional and behavioural self regulation. The current study found infant morning cortisol levels measured at 13 months of age were significantly predicted by maternal trauma experience and the subsequent PTSD symptoms of hyperarousal supporting the research of Yehuda and colleagues ( 2005 ) and implicating an epigenetic transmission of environmental experience from the mother to her offspring possibly via in utero programming of the HPA axis. Overall, maternal trauma was found to impact on both child language and self regulation development. Unexpectedly, the trauma control or resilient mothers were found to be least engaged with their infants, and their infants had the lowest language development. However, poorer language development was not mediated through dyadic emotional availability or maternal sensitivity. Maternal PTSD was found to be related to poorer child emotional and behavioural outcomes which were mediated through maternal mental health problems. Overall, the findings of the current study suggest that maternal trauma experience is associated with a biologically based mechanism occurring in both the mother and the infant which is protective for both the mother and the child's emotional health, but comes at a cost of slower infant language development. Furthermore, this mechanism appears to have broken down in the presence of maternal PTSD for both the mother and the infant with subsequent associations with greater maternal mental health problems, more problematic infant emotional and behavioural problems, and disorganised attachment. These findings have clinical implications, particularly for early intervention programs. The results need to be interpreted with caution due to the small sample size. However, the findings have broad implications in relation to resilience to trauma and the development of psychopathology and warrant repetition. / Thesis (Ph.D.)--School of Medicine, 2007.

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.

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.

<p>Posttraumatiskt stressyndrom (PTSD) kännetecknas av tre huvudsymptom: undvikande, förnekande och hyperspändhet. Även koncentrationssvårigheter, ångest, depression, flashbacks och mardrömmar är vanligt förekommande hos individer med PTSD. Flyktingar i Sverige som har varit med om krig kan uppvisa dessa symptom. Syftet med denna studie är att undersöka terapeuters upplevelser av arbete med patienter med krigsrelaterat PTSD. Intervjuer med åtta terapeuter utfördes. Gemensamma mönster i deltagarnas svar var att det är fördelaktigt att skapa en bra relation till patienter. Det är viktigt att prata om krigstrauma och de som får behandling mår bättre. Patienter är präglade av sorg och skuld och det är viktigt för dem att känna tillit och trygghet. Kropp och själ hänger ihop och det är olika och beroende på många faktorer hur individer drabbas av krig. Ofta är det andra svåra upplevelser som förvärrar krigstrauma. Terapeuter upplever sitt arbete som roligt samtidigt som tungt och anser att det är viktigt med teamarbete.</p>

This study examined measures of disease specific quality of life (DSQOL), coping, and benefit finding for differences between ethnic groups in a diverse sample of men treated for localized prostate cancer. The relationship between DSQOL and benefit finding was also evaluated, along with the relationship between coping and benefit finding. Ethnicity was evaluated as a possible moderator of the relationship between DSQOL and benefit finding, and coping was examined as a possible mediator. Results demonstrated that while minority men did show decrements in urinary function, sexual function scores were similar between groups. Furthermore, minority men reported higher levels of benefit finding as well as more frequent use of active and passive coping strategies. DSQOL was not associated with benefit finding, and the relationship was not moderated by ethnicity or mediated by coping. However, benefit finding was associated with ethnic minority status, religious group identification and less yearly income. Both active and passive coping composites were also related to benefit finding. These findings contribute to current literature on factors related to benefit finding in prostate cancer survivors. Limitations of the current study, as well as future directions are explored in the discussion.

Hyper-activation of N-methyl-D-aspartate receptors (NRs) is associated with excitotoxic cell death during secondary injury following traumatic brain injury (TBI). The efficiency of the NR is dependent on the location of receptors in membrane raft microdomains that provide a platform for coupling of NRs and effector proteins. In many neurodegenerative diseases, activation of the autophagy pathway has been suggested to contribute to glutamate excitotoxicity, but whether increased autophagy signaling contributes to pathology after TBI has not been defined. In these studies, I investigate whether membrane rafts mediate NR signaling and autophagy in cortices of adult male rats subjected to moderate TBI and in sham-operated controls. These studies demonstrate that membrane rafts of the normal rat cortex contain a novel multi-protein signaling complex that links the NR2B glutamate receptor and the autophagic protein Beclin 1. TBI caused a rapid disruption of this complex in which NR2B and pCaMKII were recruited to membrane microdomains. Alteration in NR2B-Beclin 1 association in membrane rafts resulted in activation of autophagy as demonstrated by increased expression of key autophagic proteins Beclin 1, ATG 5 and ATG 7, and significant increases in autophagic vacuoles in neurons of traumatized brains. Administration of the NR2B antagonist RO 25-6981 significantly blocked TBI-induced redistribution of NR2B signaling intermediates and Beclin 1 and delayed the increase in autophagy protein expression in traumatized cortices. Thus, stimulation of autophagy by NR2B signaling may be regulated by redistribution of Beclin 1 in membrane rafts after TBI.

Thesis (Ph. D.)--Drexel University, 2006. / Includes abstract and vita. Includes bibliographical references (leaves 92-96).