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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.
1

Differential Scoring Patterns on the Clock Drawing Test: a Comparison of Vascular Dementia and Alzheimer's Dementia.

Everitt, Alaina 05 1900 (has links)
This study examined differences in scoring patterns among those diagnosed with Alzheimer's dementia and vascular dementia on the clock-drawing test. Archival clock drawing data was retrieved on 279 patients presenting at a county hospital-based memory clinic. Analysis of drawings was based on frequency of qualitative errors, as well as an overall quantitative score. Mean comparisons found those patients with Alzheimer's dementia to perform worse on both quantitative and qualitative scoring measures. However, Pearson's chi-squared test revealed a significantly higher rate of spacing errors among subjects with vascular dementia. Such lends support to my hypothesis that impaired executive functioning in vascular dementia patients would lead to poor qualitative performance. Logistic regression found significant predictive ability for the qualitative criteria in diagnosis (χ2 = 25.49, p < .001), particularly the rate of omission (z = 8.96, p = .003) and addition errors (z = 7.58, p = .006). Such findings hold important implications for the use of qualitative criteria in cognitive screening assessments.
2

Clinical utility of a novel digitized clock drawing task

Chowdhry, Saba Akhtar 16 June 2021 (has links)
OBJECTIVE: The goal of this research was to examine the clinical utility of the digital Clock in the Box (dCIB), a novel digitized cognitive screening test. This was accomplished by (1) creating cutoff scores for the dCIB, (2) evaluating performance on the dCIB relative to established cognitive screening and standardized neuropsychological measures, and (3) determining the efficacy of the dCIB to screen for subtle cognitive deficits associated with poor vascular health. Metabolic Syndrome (MetS; clinical syndrome of three or more cardiovascular risk factors) is a rising health epidemic associated with an increased risk for cerebrovascular disease and vascular dementia. Early detection of subtle deficits associated with MetS may assist in regulation of disease progression and prevention of future vascular dementia. METHODS: A community-based sample of adults with no self-reported history of cognitive impairment was recruited for a cross-sectional study in which they completed a metabolic assessment, blood draw, and a brief neuropsychological battery consisting of the dCIB, the Mini-Mental State Exam (MMSE), and measures of executive function, memory, and attention. For part of the analysis, participants were separated into MetS (n=21) and non-MetS (n=42) groups based on current diagnostic criteria for MetS. RESULTS: Participants (N=63) were older (62.49 ± 9.16 years), educated (16.46 ± 2.76 years), and diverse with 44.4% female (n=28) and 28.6% non-White (n=18). Receiver operating characteristic (ROC) analysis and Youden’s J statistic determined the optimal cutoff value for the dCIB as 5.5 (dCIB score ≤ 6 indicating suspected impairment; dCIB score ≤ 5 indicating probable impairment). Performance on the dCIB (6.32 ± 2.32) was significantly correlated with the MMSE (28.19 ± 2.06); (Pearson’s r = 0.437, p = 0.000). The dCIB had better sensitivity (72.7%) but poorer specificity (65.4%) compared to the MMSE (sensitivity 45.5%; specificity 94.2%). Using regression modeling, the dCIB significantly predicted performance on measures of executive function, memory, and attention. In a sample stratified by vascular risk, the dCIB successfully differentiated MetS (5.33 ± 2.75) and non-MetS (6.81 ± 1.93) groups, with lower dCIB scores in the MetS group relative to the non-MetS group (F = 8.975, p = 0.004). CONCLUSION: The dCIB is a novel digitized clock drawing task designed to screen for cognitive impairment. Clinical utility for the dCIB was established by determining its test validity and demonstrating its sensitivity to detect subtle cognitive deficits in a sample with vascular risk. Because the dCIB is simple to administer and brief to complete, it may be an ideal option for routine cognitive screening in primary care settings.
3

Test hodin: normativní studie na české populaci ve stáří / The Clock Drawing Test: Normative data for Czech elderly

Mazancová, Adéla January 2015 (has links)
The diploma thesis deals with the topic of limited normative data and its aim is to report the norms of the Clock Drawing Test (CDT) in a large sample of cognitively healthy Czech elderly (N = 501; aged 60 to 99). The CDT is a commonly used tool for screening of cognitive functions. We worked with the following version of test: clock drawing with pre- drawn circle and time setting 13.45 using three different scoring systems (Babins, Slater, Whitehead, & Chertkow, 2008; Cohen, Ricci, Kibby, & Edmonds, 2000; Shulman, Pushkar Gold, Cohen, & Zucchero, 1993). As a result, we found a significant effect of age and education, but non-significant effect of gender on CDT performance in old age. Therefore normative data was calculated considering those two demografical variables; the tables present means, standard deviations and t-scores based on defined subgroups. The results indicate that CDT performance of cognitively healthy elderly is negatively influenced by age, while directly proportional effect of education. Moreover it seems that the range of scores of the test grows with increasing age. Data collected in this thesis may be used for a more effective and standardized interpretation of CDT performance in old age in both clinical context and research. We also confirmed high inter-rater reliability...
4

A reduced scoring system for the Clock-Drawing Test using a population-based sample

Jouk, Alexandra 29 October 2010 (has links)
This thesis project examined the generalizabilty of the simplified scoring system for the Clock Drawing Test developed by Lessig and her colleagues in 2008 using a population-based sample. Clock-drawings from 356 participants (80 with dementia, 276 healthy controls) from the Canadian Study on Health and Aging were analyzed using logistic regression and Receiver Operating Characteristic curves. The new scoring system reduced the Lessig system down even further to include five critical errors: missing numbers, repeated numbers, number orientation, extra marks, and number distance, and produced a sensitivity of 81% and a specificity of 68%. The results from this study improve our current state of knowledge concerning the Clock Drawing Task by validating the simplified scoring system proposed by Lessig and her colleagues among a more representative sample and provides further evidence in support of a simple and reliable dementia-screening tool.
5

Effects of cardiorespiratory fitness on cognitive function and brain plasticity on aging adults

De Siqueira, Nicolle 11 July 2018 (has links)
Alzheimer’s disease (AD) is a rapidly growing public health concern causing severe challenges to the health care system. Affecting the lives of more than 5 million Americans, it is characterized by brain-related morphological changes coupled with decrements in performance on tasks involving cognitive function such as those assessing memory and problem-solving abilities. Fortunately, current scientific research provides evidence that this trend towards rapid cognitive decline in older adults is not immutable, but rather can be attenuated through a simple adjustment to regular engagement in aerobic exercise. To date, numerous studies have associated regular cardiovascular exercise to changes in brain function and structure. In particular, aerobic exercise has been shown to have a direct effect on the hippocampus (HC), one of the earliest regions of the brain to be affected in AD, which plays an important role in learning and memory. Scientific research on animal models has demonstrated increased adult hippocampal neurogenesis (AHN), or the birth of new neurons, in the dentate gyrus (DG) subregion of the hippocampus as a response to increases in aerobic exercise. Such findings have led to the hypothesis that aerobic exercise can improve cognitive performance, more specifically hippocampal-dependent learning and memory, through the formation of new hippocampal neurons. Similarly, in human studies, previous research has shown that significant improvements in cardiovascular fitness are positively correlated with increased hippocampal volume. Structural increases in hippocampal volume are thought to be mediated by increased angiogenesis, or the generation of new blood vessels, which in turn are correlated with significant improvements in spatial memory, a task determined by memory function. The benefits of aerobic exercise, nonetheless, are not limited to the hippocampus. As people age, atrophy of the brain is also inclusive of the prefrontal cortex, a region implicated in planning and decision making. Scientific literature has shown, that similar to the hippocampus, increases in aerobic exercise, directly result to increases in grey matter volume in the prefrontal lobe and increases in white matter volume in the genu of the corpus callosum. Such structural changes in the prefrontal lobe are correlated with enhanced decision making on cognitive tasks, an essential component of executive function. For the purposes of this study, an effective method of evaluating whether changes in brain structure due to higher cardiorespiratory fitness have an association with cognitive function was through the administration of the Digital Clock Drawing Test (dCDT). The dCDT is a recently developed cognitive test based on the traditional Clock Drawing Test (CDT) that uses a digital pen and allows for the measurement of several parameters such as “Ink time” and “Think time.” Recent scientific studies report that such parameters may have a potential enhanced sensitivity to detecting cognitive change as compared to the traditional CDT. Therefore, the dCDT has come forward as an advantageous approach for testing cognitive skills in aging individuals such as those assessing executive and motor function, and semantic memory, as it happens in real time. DCDT parameters such as total time to complete the clock drawing, total ink time, total think time, total ink length, and clock size have been shown to differ significantly among subjects of varying degrees of cognitive impairment such as AD, mild cognitive impairment (MCI), and healthy, non-demented controls. Patients who were clinically diagnosed as cognitively impaired spent a greater amount of time thinking and drawing on both the command and copy clocks conditions as compared to healthy, non-demented individuals. Similarly, patients affected by greater cognitive impairments, such as AD, tended to draw smaller clocks in terms of height and width of the clock face that required less total ink length to complete the clock drawing, when compared to healthy controls and MCI participants. Findings showed that AD patients appeared to be working longer (greater time of completion) though producing less output (smaller clock and shorted ink length) as compared to non-impaired individuals. Variations of graphomotor latencies in the dCDT performance, therefore, are associated with individual’s cognitive capacities. The goal of this study is to investigate the associations between cardiorespiratory fitness based on VO2 max testing and cognitive constructs such as memory, executive function, and gross motor processing speeds as measured by graphomotor latencies and drawing patterns using the dCDT in healthy, non-demented older adults. I hypothesize that greater cardiorespiratory fitness will be negatively associated with graphomotor timed latencies in various parameters of the dCDT, given that exercise has known effects on the brain regions responsible for executive function and memory. To test these hypotheses, cardiorespiratory fitness and dCDT data from 12 sedentary older adults between the ages of 55 and 85 years from a larger study in the Brain Plasticity and Neuroimaging Laboratory at Boston University were collected and analyzed. A multiple regression analysis was used to predict the dCDT measures from individual’s cardiorespiratory fitness using estimated VO2 max levels. Results showed that cardiorespiratory fitness in older adults is inversely associated with graphomotor times in both the command and copy test conditions as predicted by our hypothesis. In particular, greater cardiorespiratory fitness was associated with shorter total ink time for both clock drawing testing conditions. These results held when controlled for age, sex, and education; higher cardiorespiratory fit older adults performed better (a shorter time is needed to achieve the same outcome) on tasks requiring greater cognitive constructs such as memory, executive function, and motor processing speeds. Therefore, it can be concluded that cardiorespiratory fitness may be a neurodegenerative protector in aging adults supporting its beneficial role as a therapeutic agent for cognitive decline in older adults.
6

Longitudinal performance of Neuropsychological Assessments in Parkinson’s Disease.

Muayqil, Taim Unknown Date
No description available.
7

[pt] CLASSIFICAÇÃO DAS ESTRATÉGIAS DE CONSTRUÇÃO DO TESTE DO DESENHO DO RELÓGIO / [en] STRATEGIES CLASSIFICATION OF CLOCK DRAWING TEST CONSTRUCTION

17 March 2021 (has links)
[pt] O teste do desenho do relógio tem ampla utilização para avaliar cognição no envelhecimento. Apesar de existirem diversos sistemas de pontuação, as estratégias de planejamento da construção do desenho não são mensuradas. O objetivo desta dissertação foi mapear, descrever e classificar as estratégias de planejamento e organização da construção do desenho do relógio. Para tanto, os diferentes padrões de sequência de ações para a construção do desenho foram classificados. 77 idosos saudáveis frequentadores da Casa de Convivência e Lazer do Rio de Janeiro foram avaliados. Os resultados mostraram heterogeneidade nos padrões adotados pelos idosos, sendo que os predominantes foram uma sequência geral (círculo-número-centro-ponteiro) e uma numérica, seguindo um padrão sequencial de ordem crescente. A estratégia círculo-número-centro-ponteiro (sequência geral) e a Quadrante (sequência numérica) foram as que tiveram associação acima do esperado, com medidas que avaliam bom desempenho em planejamento. Esta nova classificação complementa os critérios de pontuação semi-quantitativos e qualitativos existentes. / [en] The Clock drawing Test is widely used to evaluate cognition in aging. Although there are several scoring systems for the test, planning strategies of clock drawing construction are not measured. The objective of this dissertation was to map, describe and classify planning and organization strategies of clock drawing construction. Therefore, different action sequence patterns for clock drawing construction were classified. 77 healthy older adults from community centers, called Casas de Convivência in Rio de Janeiro were evaluated. The results showed heterogeneity in the patterns adopted by the elderly, and the predominant ones were a general sequence (circle-number-center-hand) and a numerical one following a sequential pattern of increasing order. The circle-number-center-hand (general sequence) strategy and the quadrant strategy (numerical sequence) frequencies were more than expected when associated with measures that evaluate good performance in planning. This new classification complements the previous existing semi-quantitative and qualitative scoring criteria.
8

[en] CONSTRUCTION STRATEGIES OF THE CLOCK DRAWING TEST: QUALITATIVE ANALYSIS AND CLINICAL VALIDITY WITH COGNITIVE IMPAIRMED OLDER ADULTS / [pt] ESTRATÉGIAS DE CONSTRUÇÃO DO TESTE DO DESENHO DO RELÓGIO: ANÁLISE QUALITATIVA E VALIDADE CLÍNICA EM IDOSOS COM COMPROMETIMENTO COGNITIVO

BARBARA SPENCIERE DE OLIVEIRA CAMPOS 25 June 2020 (has links)
[pt] Além da utilização como teste de rastreio, tem-se utilizado o Teste do Desenho do Relógio (TDR) também na avaliação de funcionamento executivo em idosos. Em dissertação de mestrado, construiu-se e validou-se um método de pontuação que classificou as estratégias de construção do TDR. A presente tese tem o objetivo de investigar as estratégias de construção do TDR em idosos com comprometimento cognitivo. 86 idosos (28 controle, 45 com transtorno neurocognitivo leve e 13 com transtorno neurocognitivo maior) participaram dos dois estudos que compuseram a tese. O primeiro analisou as estratégias de construção do TDR e o perfil neuropsicológico dos idosos e o segundo verificou a validade clínica do sistema. Os resultados apresentaram que as subcategorias associadas a melhor funcionamento executivo diminuem ocorrência à medida que o comprometimento cognitivo se acentua e as subcategorias associadas a pior funcionamento executivo aumentam frequência. Verificou-se também que a Estratégia de Sequência Geral Atípica evidenciou validade clínica para diferenciar idosos com transtorno neurocognitivo maior dos demais grupos. Conclui-se que a análise qualitativa das Estratégias de Construção do TDR tem utilidade clínica como medida de funcionamento executivo. / [en] Besides being used as a screening test, the Clock Drawing Test (CDT) has also been used to assess executive functioning in the elderly. In previous study, a scoring method that classified the Construction Strategies of the CDT was constructed and validated. This tesis aims to investigate construction strategies of CDT in elderly with cognitive impairment. 86 elderly (28 controls, 45 with mild neurocognitive disorder and 13 with major neurocognitive disorder) were the participants of the thesis. It was subdivided in two studies. The first one analyzed older adult s Construction Strategies of the CDT and neuropsychological profiles. The second one verified clinical validity of the system. Results showed that the subcategories associated with better executive functioning decrease occurrence as cognitive impairment increases while the subcategories associated with worse executive functioning increase frequency. Atypical General Sequence Strategy also showed clinical validity to differentiate older adults with major neurocognitive disorder from other groups. As conclusion, it is verified that qualitative analysis of the Construction Strategies of the CDT has clinical utility as a measure of executive functioning.

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