Background: There is currently no standard method of diagnosing the presence or severity of concussion in acute primary care settings. This pilot project is part of a larger study to develop a Computerized Concussion Assessment Tool (CCAT). Methods: A prospective observational clinical study was conducted to explore the validity of the CCAT among patients presenting to the Emergency Department at Kingston General Hospital and at Hotel Dieu Hospital (Kingston, Ontario) with minor head injury. Twenty-two patients with concussion and eighteen patients with head injury (but not diagnosed with concussion) were recruited to the study. All participants completed a background questionnaire, several neurocognitive tests and the CCAT assessment. Performance on the CCAT was compared between these two groups. Data collected during the development phase of the CCAT from a Normal Volunteers group (n=68) were used in an additional comparison. CCAT Scores for Selective Attention, Divided Attention and Memory were compared with standard neurocognitive tests through correlational analyses. In addition, the validity and clinical yield of the CCAT were investigated relative to gold standard measures. Results: After adjustment for covariates, no statistically significant differences were found between the three participant groups for any of the three primary CCAT Scores (Selective Attention, Divided Attention and Memory). Correlational analyses showed that the CCAT Selective Attention Score and the CCAT Memory Score are moderately correlated with standard neurocognitive tests. There was no correlation observed for the CCAT Divided Attention Score and its associated neurocognitive test. Conclusion: The CCAT was unable to discriminate between concussed patients and non-concussed individuals. However, moderate correlations observed between the CCAT Scores for Memory and Selective Attention and their respective neurocognitive tests support a view that there should be optimism for the future development of the CCAT. Issues related to the feasibility of the study and its administration in the emergency department setting are discussed. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2008-09-23 10:40:20.199

Impaired attention can hinder information processing at multiple levels and may explain some aspects of the cognitive decline in aging. An inefficient inhibitory system can lead to deficits in focused attention (FA). FA deficits are observed in patients with mild cognitive impairment and Alzheimer’s disease (AD). The Stroop task was applied to functional magnetic resonance imaging (fMRI) to investigate the neural correlates of FA in cognitively normal older adults (NC), patients with amnestic MCI (aMCI) and patients with mild AD. Twenty-one NC, seven aMCI and fifteen mild AD patients performed a verbal Stroop- fMRI paradigm. Both structural and T2*-weighted functional scans were acquired. In Series 0, subjects were presented with colour words printed in black ink and were asked to read the word. In Series 1 and 2, subjects were presented with colour words printed in an incongruent ink colour. Series 1 had four blocks of the ‘Read the word’ condition followed by four blocks of the ‘Say the colour of the ink’ condition. Series 2 had eight blocks of alternating ‘Read the word’ and ‘Say the colour of the ink’ conditions. SPM5 was used to detect anatomical areas with significant signal intensity differences between the two conditions. The NC group performed significantly better in the Stroop-fMRI task than the aMCI and mild AD groups. The percentage of errors on incongruent trials was significantly lower in the NC group (2%) than the aMCI (14%) and mild AD (13%) groups. The ‘Say the colour of the ink’ minus ‘Read the word’ contrast for the NC and mild AD groups yielded common areas of activation in the supplementary motor area, precentral gyrus, and inferior frontal gyrus. aMCI patients also showed activation in the precuneus, temporal and postcentral gyri. Worse performance on the Stroop-fMRI task by the aMCI and mild AD groups suggests deficits in FA. This is the first study to investigate the neural correlates of FA using the Stroop task in aMCI and AD patients. The verbal Stroop-fMRI paradigm employed in the current study provides a means to study the neural correlates of FA in older adult and patient populations. / Thesis (Master, Neuroscience Studies) -- Queen's University, 2009-12-31 11:57:52.374

No description available.

Normal ageing is associated with decline in visual, cognitive, and physical functioning, with concurrent increases in the incidence of chronic medical conditions, including cognitive disorders. Determining when age-related changes have adversely affected a person’s ability to drive safely is a complex task, particularly when cognitive disorders such as mild cognitive impairment and dementia are present. The aim of this research was to assess the utility of a number of off-road measures in predicting Pass and Fail outcomes for older drivers on a blinded on-road driving assessment with a driving specialist occupational therapist and a driving instructor, which is considered the ‘gold standard’ measure of driving ability. The off-road measures included standardized cognitive tests, computerized sensory-motor & cognitive tests, medical conditions, and personality measures. The research project comprised three studies. In Study 1 (Healthy Older Drivers study), 60 drivers with no diagnosed cognitive disorder (‘cognitively-unimpaired’), aged 70-84 years (mean age 76.7, 50% male), completed standard cognitive tests, computerized sensory-motor and cognitive tests (SMCTests™), and measures of personality. Results were used to form classification models for on-road assessment Pass and Fail outcome. Sixteen participants failed the on-road assessment. A backwards stepwise binary logistic regression model selected a measure of executive function and a computerized measure of visuomotor planning and coordination as the best predictors. Following leave-one-out cross-validation, this model was estimated to correctly predict 60% of an independent group of cognitively-unimpaired older drivers into on-road Pass and Fail groups. In Study 2 (Healthy Driver Follow-up study), 56 participants from the Healthy Older Drivers study were followed for 24 months using annual telephone interviews to assess driving behaviour, driving attitudes, medical conditions, and the occurrence of crashes and receipt of traffic offences. Official data regarding crashes and traffic offences were also obtained. The aim was to determine whether either the on-road Pass/Fail classification or the off-road measures could predict subsequent crashes and offences. Failing the on-road assessment was not associated with higher crash or offence rates and there were only two baseline measures that predicted crashes or offences (i.e., distance driven at baseline testing and, paradoxically, a lower error score on a measure of visuomotor planning and coordination). However, drivers who reported more distress associated with their medical condition(s) were more likely to have had a crash or offence at 24 months. The outcomes of the Healthy Older Drivers and Healthy Driver Follow-up studies suggest that there is little value in off-road or on-road assessment of cognitively-unimpaired older drivers due to the weak relationship with future negative driving outcomes. However, distress associated with medical conditions may be a useful measure. Study 3 (Dementia and Driving study) recruited a sample of 60 driving assessment centre referrals with mild cognitive impairment or Alzheimer’s dementia. These participants, aged 58-92 years (mean age 77.9, 60% male), performed a computerized battery of sensory-motor and cognitive tests and a formal blinded on-road driving assessment. A backwards stepwise binary logistic regression model selected measures of reaction time and movement speed of the upper limbs, visuomotor planning and coordination, and sustained attention. Following leave-one-out cross-validation, this model was estimated to correctly predict 68% of an independent group of drivers with mild cognitive impairment and Alzheimer’s dementia into on-road Pass and Fail groups. A subsample of 32 participants completed additional standard cognitive tests and provided information on medical conditions. A binary logistic regression model in this subsample was formed which selected measures of verbal fluency, the presence of heart disease, and a comprehensive cognitive screen. Following leave-one-out crossvalidation, this model would be expected to correctly classify 75% of an independent group of drivers with mild cognitive impairment and Alzheimer’s dementia into on-road Pass and Fail groups. The three measures in this model could be performed in around 35-50 min in a primary health setting. It is concluded that off-road and on-road assessment of older drivers with no diagnosis of cognitive or neurological disorder is an inaccurate and inefficient use of driving assessment resources, both for the prediction of on-road driving performance and for predicting future crashes and traffic offences. The Dementia and Driving study found a model comprising three measures that could be performed in a primary health setting with reasonable accuracy for correctly classifying people with mild cognitive impairment and Alzheimer’s dementia who go on to Pass and Fail an on-road driving assessment.

Introduction: Mild traumatic brain injury (mTBI) accounts for the vast majority of all paediatric TBI cases. It is an important public health concern, yet the long-term psychiatric and behavioural outcomes remain imperfectly understood. Aim. This study aims to examine the association between paediatric mTBI and psychiatric and offending outcomes in adulthood, while considering the impact of sex, age at injury and duration since injury on outcome. Participants: Participants with mTBI (n=57) were compared to those with moderate/severe TBI (n=62) and to orthopaedic injury controls (n=42). All participants were injured at age 17 or younger and were 18 years or older at the time of assessment. Outcome measures: Based on the DSM-IV-TR criteria, structured interviews were used to assess participants’ experience of symptoms consistent with major depressive disorder, anxiety disorders (including generalised anxiety disorder, panic attacks and panic disorder, agoraphobia, social phobia, post-traumatic stress disorder, and specific phobia), and substance abuse and/or dependence. Participants’ were asked to report on their lifetime involvement with offending, arrests, and diversions and/or convictions. Results: At age 18-31, participants with a paediatric mTBI were significantly more likely than orthopaedic injury controls to endorse symptoms consistent with major depressive disorder by 3.17 times, anxiety disorders by 5.81 times, and internalising disorders in general by 5.80 times and the risk in the mTBI group was greater than that for those with moderate/severe TBI. Females with mTBI were significantly more likely than males, by five times, to endorse an internalising disorder. Paediatric mTBI was not significantly associated with externalising problems when compared with controls; however, males with mTBI were 6.57 times more likely to endorse externalising behaviours than females. Conclusions: Paediatric mTBI is a risk factor for internalising disorders in adulthood, particularly for females. Such findings have implications for assessment and treatment of problems associated with paediatric mTBI.

Individuals with Parkinson’s disease (PD) often show cognitive impairments in addition to motor symptoms, with the majority of PD patients converting to dementia as the disease progresses. The changes in the microstructural integrity of key nodes in resting state networks (RSNs) could be a good indicator of the cognitive effects of PD on brain regions as it progresses to dementia. To assess the association between cognitive effects and microstructural change, the microstructural integrity of the regions of interest (ROIs) in 4 resting state networks (RSN), specifically the default mode network (DMN), based on DTI were obtained in three separate groups of patients with PD. One group of patients (PD-N) were cognitively normal, while the second group of patients (PD-MCI) reflect the transitional phase of mild cognitive impairment prior to dementia, and the third group of patients (PD-D) possessed a clear diagnosis of dementia. A comparison group of healthy controls (HC) were included, matched across the three patient groups. The PD-D group showed worse microstructural integrity for the majority of the ROIs across the 4 networks. The loss of structural integrity in the PD-MCI group was more selective, with some ROIs showing similar changes to PD-D, and others showing similar changes to the PD-N group. The PD-N group fail to show any changes in the structural integrity of any ROIs, relative to HC. For future study, a combined structural / functional study should be performed to examine if there are similar changes across both measures.

The shadow of stigma theory typically surrounds the research investigation of the lives of individuals with mild intellectual disabilities. McAdams’ life story theory and methodology provide a human development framework as an alternative to the prevailing framework in the field of disability. This study moves out of the shadow of otherness and examines the personal identity making process of twelve individuals with mild intellectual disabilities in the light of human development theory. Findings dispel the assumption that individuals with mild intellectual disabilities construct their lives solely through their disability. Rather, the identity making process includes the influences of socio-cultural events, religion, mentoring, advocacy, and the lived experience of disability. In this study, twelve adults with mild intellectual disabilities completed adapted life story interviews and four quantitative measures to explore the themes and patterns of agency, communion, redemption, contamination and generativity. Additional qualitative analysis expanded the range of discovery for influences in the identity making process. Following analysis of the quantitative scores, interviewees were placed in either the Higher Generativity Group or Lower Generativity Group. Analysis occurred at three levels: within case, within group and between group. Differences between the groups emerged, such as, involvement in human rights advocacy, presence of mentors and spiritual guides, and religious beliefs. Human rights advocacy provided a rich source of generativity and meaningful connection to others, politically, socially and emotionally. Turning point narratives often contained religious and redemptive content themes. While interviewees did not narrate the majority of scenes with disability centric content, one-half of the interviewees narrated disability content in their high point scenes, suggesting the positive internalization of their disability into their personal identity. The major findings confirm the importance of studying the life stories of this population from the perspective of human development theory. This study presents conclusions that impact research methodology for this population, as well as, social work research, policy development, practice and education.

Veterans of the Iraqi and Afghanistan conflicts have frequently returned with injuries such as mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD). More recently, concern has been raised about the large number of returning soldiers who are diagnosed with both. Literature exists on the neuropsychological factors associated with either alone, however far less research has explored the effects when combined (PTSD+mTBI). With a sample of 206 OEF/OIF veterans, the current study employed neuropsychological and psychological measures to determine whether participants with PTSD+mTBI have poorer cognitive and psychological outcomes than participants with PTSD-o, mTBI-o, or veteran controls (VC), when groups are matched on IQ, education, and age. The PTSD+mTBI and mTBI-o groups exhibited very similar neuropsychology profiles, and both PTSD+mTBI and mTBI-o performed significantly (α=.01) worse than VC on executive functioning and processing speed measures. There were no significant differences between VC and PTSD-o on any notable neuropsychology measures. In contrast, on the psychological measures, the PTSD+mTBI and PTSD-o groups were identical to each other and more distressed than either mTBI-o or VC. These findings suggest there are lasting cognitive impairments following mTBI that are unique to the condition and cannot be attributed to known impairments associated with distress.

Parkinson’s disease (PD) is next to Alzheimer’s disease (AD) the second most common neurodegenerative disease. PD has traditionally been characterised as a motor disorder, but more recent research has revealed that cognitive impairments are frequent. Cognitive impairments in executive functions, attention, and working memory with reliance on dopaminergic transmission, are often described as dominating the cognitive profile in early-phase PD. However, although knowledge about the neuropathology that underlies the cognitive impairments in PD has increased, its features are complex and knowledge remains insufficient. Therefore, the aim of the current thesis was to improve the understanding of how task-evoked brain responses relate to cognitive status in patients with PD, with and without mild cognitive impairment (MCI), and to evaluate the predictive value of PD-MCI in respect of prodromal Parkinson’s disease dementia (PDD). This was conducted within the “new Parkinsonism in Umeå” (NYPUM) project, which is a prospective cohort study. Patients with idiopathic PD were included in this thesis, and the patients were examined with a comprehensive neuropsychological battery and with a functional MRI (fMRI) working memory protocol. During scanning, patients conducted a verbal two-back task in which they needed to maintain and actively update relevant information, and the primary outcome measure was blood-oxygen-level-dependent (BOLD) signal. This thesis shows that patients with PD-MCI had significantly lower BOLD signal responses than patients without MCI in frontal (anterior cingulate cortex) and striatal (right caudate) regions (Study I). The altered BOLD response in the right caudate was associated with altered presynaptic dopamine binding. The fronto-striatal alterations persisted across time but without any additional change. However, decreased posterior cortical (right fusiform gyrus) BOLD signal responses were observed in patients with PD-MCI relative to patients without MCI across time (Study II). Finally, PD-MCI at baseline examination is highly predictive for prodromal PDD with a six-fold increased risk. Cognitive tests with a posterior cortical basis, to a greater extent, are predictive for prodromal PDD than tests with a fronto-striatal basis. The observed working memory related alterations in patients with PD-MCI suggest that early cognitive impairments in PD are linked to fronto-striatal dopaminergic dysfunction. The longitudinal development of cognitive impairment in PD reflects additional posterior cortical dysfunction. This might reflect a dual syndrome, with dopamine-depleted fronto-striatal alterations that characterise PD-MCI in general, whereas additional posterior cortical cognitive alterations with a non-dopaminergic basis to a greater extent characterise prodromal PDD. If, and how, the two potential syndromes interact, is still unclear. Thus, this thesis provides information on cognitive neuropathological changes in PD that might contribute to more relevant choices of pharmacotherapy and diagnostic accuracy in respect of PDD. However, additional large-scale longitudinal imaging studies are needed to further clarify the neuropatholgogical features of PD-MCI in respect of prodromal PDD.

Introduction-Physical activity can reduce the risk of contracting many of the 'diseases of the sedentary', such as coronary heart disease and cancer (Blair et al., 1996). Recognition of this protective effect has led to the development of many programmes designed to promote the benefit of participation in sport and physical exercise (Hillary Commission, 1993; Nicholl et aI., 1995). With participation in sport, especially contact sport, the risk for injuries increases, including injuries to the head and neck (Wilberger, 1993; Wekesa et al., 1996; Pettersen, 2002). Mild traumatic brain injuries (MTBI) or concussion as used interchangeably in the literature (Maroon et al., 2000; Wills & Leathem, 2001) are an important public health concern, due to the high incidence and frequently persisting symptomatology (Evans, 1992). Mild traumatic brain injury is defined as a complex patho-physiological process affecting the brain induced by traumatic biomechanical forces (Aubry et al., 2002; McCrory et al., 2004). A sub-concussive injury or very mild traumatic brain injury (vMTBI) may be defined as an apparent brain insult with insufficient force to cause hallmark symptoms of concussion (Jordan, 2000; Webbe & Bath, 2003). The high incidence of sport related head injuries in South Africa is alarming, although the prevalence thereof is unknown and difficult to assess, as the seemingly trivial injuries frequently remain unreported (Roux et al., 1987). This is especially applicable in sport where a milder form of head injury is common. This is cause for concern as cumulative head injuries traditionally regarded as trivial or 'minor' may result in players running the risk of increasingly negative consequences following repetitive 'minor' head injuries. In contact sport such as rugby, players are at great risk of sustaining repetitive mild traumatic brain injuries. The negative outcome following these repetitive minor head injuries has been demonstrated by numerous studies on boxers and other athletes exposed to repeated MTBI and vMTBI (McLatchie et aI., 1987). The incidence of vMTBI has not yet been researched in school rugby and this study is the first to report the incidence of vMTBI in a secondary school rugby team. Obiectives - The objectives of this study were to determine the incidence, the neuropsychological consequences and the effect on the academic performance of repeated mild (MTBI) and very mild traumatic brain injuries (vMTBI) in a secondary school rugby team during one playing season. Methods - A cohort of 35 secondary school male rugby players divided into a vMTBI (group 1) (n=26) and a MTBI (group 2) (n=9) from a local secondary school's first and second team, was followed for a full competitive season by a trained Biokineticist, who was present at all the games and contact sessions played. All vMTBI and MTBI and the severity of these injuries were documented. A control (group 3) that consisted of 10 secondary school non-rugby players were compared with the vMTBI and MTBI groups. The incidence of repeated MTBI and vMTBI in a secondary school rugby team were gathered by questionnaires and observation next to the field by a trained Biokineticist. Pre-season and post-season neuropsychological tests were conducted on the research groups and the control group. The neuropsychological tests that were conducted on the three groups were the Colour Trial Test 1 and 2 (CTT 1 + 2), the Symbol Digit Modalities Test (SDMT), the Wechsler Memory Scale-Revised (WMS-R) and the Standardised Assessment of Concussion (SAC). After each match played throughout the season the research group also completed a SAC test. The academic results of the final examination (year 1) of the year of the specific rugby season were obtained, as well as the academic results of the final examination of the preceding two years (year 2 and 3). The programme STATISTICA (version 7.0, Stat soft, Tulsa, OK) was used to analyse the data. Descriptive statistics, one-way ANOVA's, two-way repeated measures ANOVA's, Post-hoc Tuckey HSD analysis and Pearson's product moment correlation were used for all the statistical analyses. Results - This study of a secondary school rugby team has shown 726 vMTBI's and 18 MTBI's throughout one rugby season. This relates to 1951 vMTBI's per 1000 player hours and 48 MTBI's per 1000 player hours. Reductions in delayed memory (p=O.O1)from preseason to post-season in a group of players with repetitive vMTBI's during a single rugby season were found. This was the first evidence of possible neurocognitive deficits towards delayed memory in very mild traumatic brain injuries at secondary school level. Statistically significant (p<=0.05)results of the SAC test totals between both the vMTBI and MTBI groups were documented in the different games throughout the rugby season and compared with the baseline test. No statistically significant differences (p<=0.05) between the pre-season and post-season's scores of the SAC test totals were documented. A decrease in academic performance in the subject Afrikaans (year 1 compared with year 2) with a p-value of p=O.O17(group 1) and p=O.O16(group 2) respectively was found. Conclusion - The findings of this study indicate a high incidence of vMTBI in a cohort of secondary school rugby players in one season, a statistically significant reduction (p=O.O1 )in delayed memory of the vMTBI rugby players and a statistically significant decrease in academic performance p=O.O17 (group 1) and p=O.O16 (group 2) in the subject Afrikaans from year 1 to year 2 final examinations. / Thesis (Ph.D. (Human Movement Science))--North-West University, Potchefstroom Campus, 2006.