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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
351

Terapeuters arbete med krigsrelaterat posttraumatiskt stressyndrom

Avdic, Aida January 2007 (has links)
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.
352

The Neuropsychological Mechanisms of Avoidant Coping Post Traumatic Brain Injury

Krpan, Katherine Maria 13 April 2010 (has links)
Many people who sustain traumatic brain injuries (TBI) have poor psychosocial outcomes. Previous research has indicated that poor outcomes are related to the use of avoidant coping following TBI, although the mechanisms of this relationship are not clear. The major pathological consequence of TBI is damage to the frontal lobes and/or their connections, resulting for most people in executive and/or affective dysfunction. The purpose of this dissertation study was to delineate the neuropsychological, psychiatric, personality and physiological mechanisms of avoidant coping following TBI. Controls and people with TBI completed the Baycrest Psychosocial Stress Test (BPST), where coping behaviour was observed directly, and physiological measures were recorded. Participants also completed a neuropsychological test battery, and a series of questionnaires assessing coping, psychiatric status, personality and outcomes. There were no significant differences between groups in self reported coping. However, the control and mild TBI group engaged in more planful than avoidant behaviour on the BPST. As a group, individuals with moderate-to-severe injury, in contrast, engaged in more avoidant than planful behaviour. However, analysis of individual differences in coping behaviour within the moderate-to-severe group revealed a bimodal distribution, allowing classification of people in this group as ‘planners’, or ‘avoiders’ (this distribution was not evident in the mild TBI group). Within the moderate-to-severe group, planners had better executive function, were more reactive to stress (psychologically and physiologically), performed better on the speech task during the BPST, and had greater return to productivity. However, planners also had worse psychosocial outcomes as compared to the avoiders. This was the first study, to the author’s knowledge, to examine coping behaviour during a simulated real-world stress test. Results indicate that behavioural measures of coping, such as the BPST, are more sensitive to changes in coping post TBI than are self and significant other reported questionnaires. Results also demonstrate that executive function and psychological and physiological reactivity are important factors that contribute to coping following moderate-to-severe TBI. These data raise important questions about the challenges of targeting coping through rehabilitation.
353

Intentional traumatic brain injury in Ontario, Canada

Kim, Hwan 31 August 2011 (has links)
Violence and traumatic brain injury (TBI) are two major public health concerns. This thesis is comprised of three different research topics; the epidemiology of intentional TBI in Ontario, discharge against medical advice (DAMA) as an undesirable outcome of acute stage, and functional changes after receiving rehabilitation care. To study these areas, three different datasets from the Canadian Institute for Health Information (CIHI) were used. The first epidemiological study on intentional TBI identified 1,409 (8.0%) intentional TBIs and 16,211 (92.0%) unintentional TBIs. Of the intentional TBIs, 389 (27.6%) were self-inflicted TBI (Si-TBI) and 1,020 (72.4%) were other-inflicted TBI (Oi-TBI). The most common causes of Si-TBI were “jumping from high places” and “firearms”. Major causes of Oi-TBI were ‘fight and brawl” and “struck by objects”. Si-TBI was associated with younger age, female gender, and having a history of alcohol/drug abuse. Oi-TBI was also associated with younger age and having an alcohol/drug abuse history and also with male gender. The second study on discharge against medical advice found that 446 (2.84%) TBI patients left hospitals without medical advice. DAMA was significantly associated with intentional injuries in those with self-inflicted TBI and other-inflicted TBI. DAMA was also associated with younger age and a history of alcohol/drug abuse. Using univariate analyses, the third study found that people with intentional TBI had significantly lower FIM gains in the motor area and significantly lower relative function gains (as measured by Montebello Rehabilitation Factor Score) in the cognitive area. Multivariate analyses of the same data showed that intentional TBI was also associated with lower cognitive relative gains, while controlling for age, gender, alcohol/abuse history, and other demographic and clinical variables. Persons with intentional TBI were found to be less likely to be discharged home, controlling for other relevant confounders. In conclusion, a person who has been injured due to assault or suicidal attempt may need more individualized care as they may be at greater risk for adverse rehabilitation outcomes. These findings regarding people with intentional TBI provide a basis for enhancing efforts on prevention of violence-related TBI and DAMA, and also for improving rehabilitation programs and discharge plans for this vulnerable population.
354

The Neuropsychological Mechanisms of Avoidant Coping Post Traumatic Brain Injury

Krpan, Katherine Maria 13 April 2010 (has links)
Many people who sustain traumatic brain injuries (TBI) have poor psychosocial outcomes. Previous research has indicated that poor outcomes are related to the use of avoidant coping following TBI, although the mechanisms of this relationship are not clear. The major pathological consequence of TBI is damage to the frontal lobes and/or their connections, resulting for most people in executive and/or affective dysfunction. The purpose of this dissertation study was to delineate the neuropsychological, psychiatric, personality and physiological mechanisms of avoidant coping following TBI. Controls and people with TBI completed the Baycrest Psychosocial Stress Test (BPST), where coping behaviour was observed directly, and physiological measures were recorded. Participants also completed a neuropsychological test battery, and a series of questionnaires assessing coping, psychiatric status, personality and outcomes. There were no significant differences between groups in self reported coping. However, the control and mild TBI group engaged in more planful than avoidant behaviour on the BPST. As a group, individuals with moderate-to-severe injury, in contrast, engaged in more avoidant than planful behaviour. However, analysis of individual differences in coping behaviour within the moderate-to-severe group revealed a bimodal distribution, allowing classification of people in this group as ‘planners’, or ‘avoiders’ (this distribution was not evident in the mild TBI group). Within the moderate-to-severe group, planners had better executive function, were more reactive to stress (psychologically and physiologically), performed better on the speech task during the BPST, and had greater return to productivity. However, planners also had worse psychosocial outcomes as compared to the avoiders. This was the first study, to the author’s knowledge, to examine coping behaviour during a simulated real-world stress test. Results indicate that behavioural measures of coping, such as the BPST, are more sensitive to changes in coping post TBI than are self and significant other reported questionnaires. Results also demonstrate that executive function and psychological and physiological reactivity are important factors that contribute to coping following moderate-to-severe TBI. These data raise important questions about the challenges of targeting coping through rehabilitation.
355

Intentional traumatic brain injury in Ontario, Canada

Kim, Hwan 31 August 2011 (has links)
Violence and traumatic brain injury (TBI) are two major public health concerns. This thesis is comprised of three different research topics; the epidemiology of intentional TBI in Ontario, discharge against medical advice (DAMA) as an undesirable outcome of acute stage, and functional changes after receiving rehabilitation care. To study these areas, three different datasets from the Canadian Institute for Health Information (CIHI) were used. The first epidemiological study on intentional TBI identified 1,409 (8.0%) intentional TBIs and 16,211 (92.0%) unintentional TBIs. Of the intentional TBIs, 389 (27.6%) were self-inflicted TBI (Si-TBI) and 1,020 (72.4%) were other-inflicted TBI (Oi-TBI). The most common causes of Si-TBI were “jumping from high places” and “firearms”. Major causes of Oi-TBI were ‘fight and brawl” and “struck by objects”. Si-TBI was associated with younger age, female gender, and having a history of alcohol/drug abuse. Oi-TBI was also associated with younger age and having an alcohol/drug abuse history and also with male gender. The second study on discharge against medical advice found that 446 (2.84%) TBI patients left hospitals without medical advice. DAMA was significantly associated with intentional injuries in those with self-inflicted TBI and other-inflicted TBI. DAMA was also associated with younger age and a history of alcohol/drug abuse. Using univariate analyses, the third study found that people with intentional TBI had significantly lower FIM gains in the motor area and significantly lower relative function gains (as measured by Montebello Rehabilitation Factor Score) in the cognitive area. Multivariate analyses of the same data showed that intentional TBI was also associated with lower cognitive relative gains, while controlling for age, gender, alcohol/abuse history, and other demographic and clinical variables. Persons with intentional TBI were found to be less likely to be discharged home, controlling for other relevant confounders. In conclusion, a person who has been injured due to assault or suicidal attempt may need more individualized care as they may be at greater risk for adverse rehabilitation outcomes. These findings regarding people with intentional TBI provide a basis for enhancing efforts on prevention of violence-related TBI and DAMA, and also for improving rehabilitation programs and discharge plans for this vulnerable population.
356

Estudio de la atención al traumatismo craneoencefálico de adultos en unidades de cuidados intensivos de referencia para esta patología en Cataluña

Gracia Gozalo, Rosa Maria 20 June 2006 (has links)
La patología de origen traumático, cuarta causa de mortalidad y primera en cuanto a años perdidos, es un relevante problema de salud, que ocasiona además una elevada morbilidad e incapacidad y un alto coste sanitario y social. El conocimiento de su abordaje se ha realizado mediante el análisis de bases de datos de pacientes y encuestas a profesionales. El presente trabajo de investigación va dirigido a conocer si la asistencia al paciente adulto con TCE en las UCI catalanas de referencia para esta patología es comparable en cuanto a epidemiología, abordaje y resultados, a los que muestra la literatura referente a otros países de nuestro entorno. Se planteó un estudio con un objetivo principal doble, por un aparte describir las características demográficas y clínicas de los pacientes y por otro analizar el abordaje terapéutico y la monitorización. Como objetivos secundarios se plantearon conocer la variabilidad de los apartados anteriores según la gravedad del TCE, conocer si la práctica clínica se adhería a las principales recomendaciones de las Guías de Práctica Clínica vigentes y conocer el resultado neurológico final de los pacientes, identificando las posibles variables epidemiológicas estudiadas que pudieran influir en el resultado neurológico y la presencia de de insultos secundarios que se producen. Se realizó un estudio observacional, multicéntrico y prospectivo en las 7 UCIs catalanas de referencia para esta patología. Se recogieron datos demográficos, clínicos, radiológicos, monitorización, terapéuticos, complicaciones y de resultado de los pacientes que ingresaban en una UCI afectos de un TCE, con o sin politraumatismo durante los primeros 15 días de estancia. Se incluyeron pacientes 370 pacientes durante un año.Los principales resultados muestran un predomina el sexo masculino, edad media de 40 años, causa principal el accidente de tráfico. Un 36% de los casos ingresaron directamente en el centro de referencia pero únicamente el 26% en los primeros 60 minutos. El perfil de gravedad del TCE fue un 53% Graves, 27% Moderados y 20% Leves, con una lesión encefálica predominante tipo II de Marshall (39%). La presencia de HSA fue del 49%. Se monitorizó la PIC en el 69% de los TCE grave, la SjO2 en el 27% y el DTC en el 50%. La intensidad de la monitorización y el uso de la terapéutica se incrementa de acuerdo a la mayor gravedad del paciente. Hay una alta adherencia para las recomendaciones de las guías de práctica clínica en lo que hace referencia a la utilización de monitorización sistémica y neurológica, la utilización de barbitúricos, y menor en cuanto a la utilización de corticoides, e hiperventilación. La tasa global de mortalidad en UCI fue del 22%, un 31 % para los graves. Las variables explicativas de "éxitus" fueron el estado de las pupilas, el tipo de lesión radiológica, el sexo y la gravedad del TCE. La presencia de complicaciones prehospitalarias (hipoxia, hipotensión, broncoaspiración, paro cardiorrespiratorio, hipotermia o convulsiones) se constata en el 15% de los pacientes y se asocia de forma acumulativa con un mal resultado.Como conclusión general este trabajo de investigación apoya la hipótesis inicial de que la atención al TCE en las UCI catalanas estudiadas es comparable en cuanto a epidemiología, abordaje y resultados, a los que muestra la literatura referente a otros países de nuestro entorno. Palabras clave:Head injury, traumatic brain injury, neurocritical care. / Trauma disease represents the fourth cause of mortality in frequency and the first one in terms of lifetime waste. It constitutes a significant health problem that provokes a high morbidity and incapacity in addition to striking health and social costs. Since now, its management approach has been done through patient data bases analysis and surveys directed to professionals. This research report attempts to elucidate epidemiologic, management and clinical results' comparability between actual adult BTI clinical practice in Catalan ICU's, which are of reference for this pathology, and practice shown in medical literature in our environment. The study was planned with a double main objective; for one part, to describe demographic and clinical patient characteristics, and for the second part, to analyse patient monitoring and therapeutic management. As secondary objectives we proposed to explore variability by BTI clinical severity, adherence rate to recommendations addressed in Clinical Practice Guidelines in force, and patient neurological outcome, identifying those epidemiologic parameters probably influencing neurological outcome, apart from secondary insults incidence. An observational and prospective study was conducted in 7 reference ICU's in Catalonia. Patient data collected covered demographic, clinical, radiological, monitoring and therapeutic aspects, besides complications and outcome variables for patients that were admitted in the ICU with a BTI diagnosis, with or without multiple trauma, that were followed in their length of stay for a 15-day period. A total of 370 patients were included in the study period of 1 year.Main results show a predominance of males with a mean age of 40, being traffic accident the main cause of BTI. 36% were directly admitted to the reference hospital, but only 26% were admitted in the first hour after the accident. The BTI severity profile was: 53% severe, 27% moderate and 20% mild, being the highest prevalence (39%) type II Marshall encephalic injury. The existence of SH was 49%. ICP was monitored in 69% of severe patients and SjO2 in 27% and TCD in 50%. Monitoring and therapeutic use was shown to increase depending on the higher patient severity. Close adherence to clinical guidelines recommendations was proven for systemic and neurological monitoring and barbiturate use, and was lesser the adherence for hyperventilation and corticoid utilization. ICU mortality rate was 22%, raising 31% for severe patients. Dependent variables for mortality were found to be pupil status, type of radiological finding, sex and BTI severity. Pre-hospital complications (hypoxia, hypotension, bronchial aspiration, cardiac arrest, hypothermia, convulsions) were found in 15% of patients, and are cumulative associated with a worse outcome.As a general conclusion, this research report supports the initial hypothesis that BTI clinical practice reviewed in reference Catalan ICU's, is comparable to practice in other countries of our environment, as is shown from the medical literature published.
357

Patients, Partners, and Practitioners: Interactions and Meaning- Making Following Spinal Cord Injury

Bender, Alexis A. 01 August 2011 (has links)
Sustaining a Spinal Cord Injury at any point in time is life altering – physically, emotionally, and financially – for all persons affected by the injury, but it can place unique challenges on younger married couples. This study examines the transition to injury for 18 couples (ages 21-55). Data were collected using individual interviews with each partner at three time points following injury, as well as observation in the rehabilitation setting (Creekview). This resulted in 96 individual interviews and 300 hours of observation. Using a combination of the life course perspective and cognitive sociology as guiding theoretical frameworks and grounded theory analysis, I examined how the health care institution influenced the couples’ relationships during their rehabilitation stay and the subsequent transition home. Overall, this study found that Creekview shaped a thought community that emphasizes a return to walking and high levels of physical recovery. Patients who achieved these goals constructed positive narratives about the future while those with lower levels of recovery constructed negative narratives over time. Additionally, because of the dominant medical narrative of wait and see regarding physical recovery, many respondents constructed fuzzy narratives about the future that reflect ambiguity about what life would look like following injury. Additionally, Creekview staff and couples accepted and reinforced the dominant cultural narrative that women are natural caregivers, but larger social structures of class, gender, and the division of paid and unpaid labor work together to push some women into caregiving faster or prevent other women from engaging in caregiving. Expanding on Aneshensel et al.’s (1995) caregiving career, this study examines how younger couples move through the caregiving career when the expected outcome is not long-term care placement or death. This study identified three main types of caregivers, each with their own path of caregiving – Naturalized, Constrained, and Resistant caregivers. Overall, the transition to injury is complex for patients and partners and this study highlights some of the ways the marital relationship is affected by a non-normative, unexpected transition.
358

Adaptive Functioning following Pediatric Traumatic Injury: The Relationship between Parental Stress, Parenting Styles, and Child Functional Outcomes

Micklewright, Jackie Lyn 18 June 2009 (has links)
Moderate and severe pediatric traumatic brain injuries (TBI) are associated with significant familial stress and child cognitive and adaptive sequelae (Taylor et al., 1999). Research has demonstrated a relationship between familial stress and resources and child recovery of functioning following TBI (Taylor et al., 1999). We built on these findings by examining authoritarian parenting values and styles as a mediator of the relationship between parental stress and child adaptive outcomes 12-36 months following TBI or orthopedic injury (ORTHO). Participants were 21 children/adolescents with traumatic brain injuries and 23 with orthopedic injuries and one of their parents/guardians. Parents completed measures of demographics, parental stress, parenting values and styles, and child adaptive functioning. Child participants completed brief demographic questionnaires and intelligence screeners. Moderation was examined using hierarchical multiple regression. Mediation and moderated mediation were examined using bootstrapping tests of the indirect effect of parental stress on child adaptive functioning. After controlling for family insurance status, higher levels of parental stress were associated with reduced child adaptive functioning in the TBI group but not the ORTHO group. An examination of the mediational analyses revealed that higher levels of parental stress were associated with a greater reliance on authoritarian parenting styles, which was associated with reduced overall adaptive functioning and daily living skills across the two injury groups. Therefore, across groups, the relationship between parental stress and child overall adaptive functioning and daily living skills was found to be partially mediated by an authoritarian parenting style. Moderated mediation results revealed the presence of a significant interaction and 95% confidence interval on the socialization domain and indicated that the relationship between authoritarian parenting styles and child adaptive social skills differed significantly between the two groups. Our findings suggest a relationship between parental stress, authoritarian parenting styles, and child adaptive functioning in the 12-36 months following pediatric traumatic injury. Future research should explore the association among these, as well as other potentially mediating variables, both within and between the two groups with the goal of further elucidating the relationship between familial/environmental variables and child adaptive functioning following traumatic brain and orthopedic injury.
359

High-level mobility in adults with traumatic brain injury and adults bom with very low birth weight

Hamborg, Inger Helene January 2012 (has links)
Background and aim: Persons sustaining different types of brain injury may experience difficulties with advanced mobility. Both persons with traumatic brain injury (TBI) and persons born with very low birth weight (VLBW) have similar brain abnormalities, such as reduced white matter and connectivity, and may thus experience similar mobility problems. However, few studies have assessed advanced motor abilities, and none have compared mobility functions in adult TBI and VLBW populations. Our aim was to investigate high level mobility functions in adults with TBI and VLBW adults compared to matched controls, and to compare high-level mobility in TBI and VLBW adults. Methods: Participants consisted of 22 subjects (mean age 22.9 ± 2.0 yrs) with chronic traumatic brain injury, and 35 subjects (mean age 22.5 ± 0.7 yrs) born preterm with birth weight (below 1500 grams). Two TBI participants were not able to complete all test items due to pain. The VLBW group included three subjects with cerebral palsy (CP). Each group was matched with its own control group, consisting of 24 subjects each from the same geographical area matched by age and sex. Mean age in the control group was 23.3 ± 1.8 yrs for TBI and 22.8 ± 0.5 yrs for VLBW. Advanced mobility functions were assessed by the High-level Mobility Assessment Tool (HiMAT), which consists of 13 timed mobility tasks, with a maximum total HiMAT score of 54. Results: Mean total HiMAT score in the TBI group was 47.0 ± 7.7 compared to 50.3 ± 3.9 for the controls (U=193, p=0.116). Three of 13 mobility tasks differed significantly from the control group: ‘walking’, ‘walk over obstacle’ and ‘bound non-affected leg’. When the two subjects who reported pain were excluded from the analysis, mean total HiMAT score was 48.9 ± 4.9 (U=193, p=0.264), with ‘walking’ and ‘walk over obstacle’ remaining significantly different from the control group. In the TBI group, nine (40.9%) participants performed at or below the 5th percentile compared to 6 (25%) of the TBI controls. Mean total HiMAT score in the VLBW group was 45.1 ± 7.8 compared to 49.9 ± 3.5 in its control group (U = 256, p=0.011). Five of the 13 mobility task scores were significantly different from the control group: ‘walking backwards’, ‘running’, ‘hop affected leg’, ‘bound affected leg’, and ‘bound non-affected leg’. When the three subjects with CP were excluded, mean total HiMAT score was 46.8 ± 5.5 in the VLBW group (U=256, p=0.033) and three mobility task scores remained significantly different from the controls: ‘walking backwards’, ‘hop affected leg’ and ‘bound non-affected leg’. In the VLBW group, 17 (48.6%) participants performed at or below the 5th percentile compared to 4 (16.7%) of the VLBW controls. When directly compared to the VLBW group, the TBI group had (OR 0.733, CI 0.249 – 2.154) lower risk for performing at or below the 5th percentile, although not significant. Conclusions: Compared to controls, adults with TBI had reduced high-level mobility in specific tasks. Adults born with VLBW had reduced overall high level mobility. Furthermore, the HiMAT seems to be a valuable tool for assessing high-level mobility in VLBW populations, and should be formally tested for further use. Keywords: High-level mobility, high-level mobility assessment tool, traumatic brain injury, very low birth weight
360

The Investigation of Long-term Cognitive Changes after Mild Traumatic Brain Injury using Novel and Sensitive Measures

Ozen, Lana January 2012 (has links)
Memory and concentration problems are frequently reported long after experiencing a mild traumatic brain injury (mild TBI), though conflict with null findings of deficits on standard neuropsychological tests. Experimental research shows that these inconsistencies are, in part, due to the simplicity of neuropsychological tests. As well, past research suggests that when neuropsychological deficits are occasionally detected within this population, they could be influenced by diagnosis threat: an expectation bias for impaired performance when individuals are merely informed that cognitive problems may be experienced following a mild TBI. The main goal of this thesis was to specify the long-term cognitive effects of mild TBI, with the prediction that, while cognitive complaints may be over-reported due to diagnosis threat, significant deficits can be detected using sensitive measures in experimental paradigms. Experiment 1 sought to document whether diagnosis threat influenced self-report of everyday attention and memory problems and neuropsychological task performance in individuals with a remote history of mild TBI. We found that undergraduate students with a mild TBI were significantly more likely to report having attention and memory failures in their daily lives when exposed to diagnosis threat, compared to undergraduate students not exposed to diagnosis threat. These findings call into question the efficacy of using of self-report measures to identify long-term cognitive deficits following a mild TBI. In an attempt to further specify persistent significant cognitive deficits, we designed two different experimental paradigms that uniquely manipulated the demand place on executive processes, as past research suggested deficits emerge only when tasks require considerable cognitive resources. In Experiment 2a, we manipulated processing load on a visual working memory task, across two conditions, while also limiting the potential effect of diagnosis threat. While self-report and neuropsychological measures of attention and memory did not differentiate the groups, the mild TBI group took significantly longer to accurately detect repeated targets on our working memory task. Accuracy was comparable in the low-load condition and, unexpectedly, mild TBI performance surpassed that of controls in the high-load condition. Temporal analysis of target identification suggested a strategy difference between groups: mild TBI participants made a significantly greater number of accurate responses following the target’s offset, and significantly fewer erroneous distracter responses prior to target onset, compared to controls. In Experiment 2b we also examined whether manipulating executive processing demands would differentiate mild TBI from controls, this time on a routine action task that required participants to learn a sequence of hand movements to targets. While not significant, we found a trend such that mild TBI participants were slower to respond on trials with a large executive demand compared controls, while no differences were found on trials with relatively low executive requirements. Results from Experiments 2a and 2b provide stronger evidence for mild TBI-related slowing during a working memory task with an executive component compared to a skilled action task that also had an executive component, but placed minimal demand on memory. To more precisely identify the brain basis of this cognitive slowing, in Experiment 3 we administered a visual n-back task in which we systematically increased working memory demands from 0- to 3-item loads. We found that, compared to controls, mild TBI participants showed a reduction in P300 amplitude, conceptualized as an index of available cognitive resources for stimulus classification. While no late stage response differences were found between groups, P300 amplitude was negatively correlated with response times at higher loads in both control and mild TBI participants. Findings suggest that high functioning young adults who sustained a mild TBI in their remote past, have a reduced amount, or inefficient recruitment of, cognitive resources for target detection; a potential mechanism underlying mild TBI-related response slowing on tasks that place a heavy demand on processing resources. Similar to the effects of mild TBI, aging is also known to negatively impact cognition. In Experiment 4, we examined whether TBI-related deficits persist into older adulthood, and compound the negative effect of aging on cognition. We administered the same working memory task as in Experiment 2a, along with a variety of neuropsychological tests in order to investigate the effect of a TBI sustained an average of 50 years in the past. While no group differences emerged on our experimental working memory task, older adults with a history of 1 or 2 TBIs performed significantly worse than non head-injured older adults only on neuropsychological measures of attention that had an executive component. Such results suggest that a remote TBI sustained early in life further compounds normal age-related cognitive decline. Together, these experiments help specify the measures that best detect long lasting cognitive changes following TBI. Particularly, our findings provide a potential explanation for why long-term cognitive deficits are difficult to identify in the young mild TBI population: the majority of neuropsychological tests are insensitive to minor changes in information processing speed and, as a result, the execution of slowing strategies to maintain accuracy may go undetected. Our findings also demonstrate the importance of investigating longer-term effects of TBI, as they may be chronic and impact cognitive task performance in old age, amplifying normal age-related cognitive deficits.

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