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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.
121

Perfil neuropsicológico de sujeitos com comprometimento cognitivo leve de uma amostra comunitária da cidade de São Paulo (Brasil) / Neuropsychological profile of subjects with Mild Cognitive Impairment from a community sample from São Paulo (Brazil)

Maria del Pilar Quintero Moreno 27 September 2006 (has links)
INTRODUÇÃO: O impacto na saúde pública dos transtornos neuropsiquiátricos como a demência e o comprometimento cognitivo tem aumentado com o aumento da população idosa de países em desenvolvimento como o Brasil. O diagnóstico destas entidades requer confirmação objetiva da presença de prejuízo cognitivo, para a qual recomenda-se o uso de testes neuropsicológicos. OBJETIVO: Comparar o perfil neuropsicológico de sujeitos com comprometimento cognitivo leve (CCL), com um grupo de sujeitos considerados normais, provenientes de uma amostra comunitária identificada em um estudo de prevalência de demência e comprometimento cognitivo na cidade de São Paulo. MÉTODO: A amostra total (1.563 sujeitos de 60 ou mais anos de idade) foi selecionada aleatóriamente em três áreas com diferentes perfis sócio-econômicos em São Paulo. Os sujeitos foram classificados como CCL amnéstico, utilizando critérios adaptados de Petersen et al. (1999) usando os seguintes instrumentos: um questionário de queixas de memória de 10-pontos, Mini Exame do Estado Mental (MEEM), FOME e a escala internacional de atividades da vida diária (ADL-IS). Em uma segunda fase, os sujeitos foram submetidos novamente ao MEEM, ADL- IS, questionário (SRQ 20) para identificar sintomas psiquiátricos, e uma bateria de testes neuropsicológicos para avaliar: atenção (Dígitos de WMS-R, Trail Making Test), memória (Memória Lógica e Reprodução Visual de WMS-R, Selective Reminding Test - Buschke), praxia (desenho do relógio, Cubos do WAIS-R), linguagem (Teste de Nomeação de Boston, fluência verbal - animais) e QI estimado (Vocabulário e Cubos do WAIS-R). RESULTADOS: trinta e sete indivíduos classificados como CCL amnéstico e trinta e um classificados como normais completaram a avaliação. Não foram encontradas diferenças significativas entre os grupos quanto a: idade, gênero, anos de escolaridade, estado civil, classe social ou pontuações no MEEM ou no SRQ-20. Houve diferenças significativas entre os dois grupos nos seguintes testes: Trail Making A, Memória Lógica (evocação imediata e tardia), Selective Reminding Test (aprendizagem total), Reprodução Visual (evocação Imediata e tardia), Nomeação de Boston (nomeação e paragnosias), Cubos e QI Estimado, sendo que os indivíduos com CCL tiveram pior desempenho que os controles. CONCLUSÕES: Os achados sugerem que submetidos a uma bateria neuropsicológica abrangente, os dois grupos estudados apresentam diferenças significativas no desempenho não somente da memória mas também em outros domínios como atenção, linguagem e praxia. Estes achados sugerem que o conceito de CCL múltiplos domínios pode ser mais útil que o conceito de CCL amnéstico, quando são avaliados idosos que pertencem a uma amostra comunitária / BACKGROUND: The impact on public health of neuropsychiatry disorders as dementia and mild cognitive impairment is growing as the population grows older in developing countries as Brazil. The diagnosis of these entities requires confirmation of cognitive impairment assessed by neuropsychological tests. OBJECTIVE: Compare the neuropsychological profile of Mild Cognitive Impairment (MCI) individuals and Normal subjects from a community sample identified in a Prevalence Study of Dementia and MCI in São Paulo. METHOD: The total sample (1.563 subjects over 60 years old) was randomly selected from three different social class areas of São Paulo. The subjects were classified as amnestic MCI following criteria adapted from Petersen et al. (1999) using the following instruments: 10-point questionnaire on memory complaints, Mini Mental State Examination (MMSE), Fuld Object Memory Evaluation, and Activities of Daily Living - International Scale (ADL-IS). In a second phase, patients were submitted to the MMSE, ADL- IS, Self Reporting Questionnaire (SRQ 20) to identify psychiatric symptom, and Neuropsychological test battery to evaluate: Attention (Digit Symbol from WMS-R, Trail Making Test), Memory (Logic Memory and Visual Reproduction from WMS-R, Selective Reminding Test - Buschke 1973), Praxis (Clock drawing, Block Design - WAIS-R), Language (Boston Naming Test and Verbal Fluency - animal) and Intelligence (Estimated Intellectual Quotient - Vocabulary and Block Design from WAISR). RESULTS: 37 subjects classified as amnestic MCI and 31 Normal controls completed the evaluation. We did not found significant differences between the two groups in age, gender, years of education, civil status, social class, MMSE and SRQ-20 scores. There were significant differences between MCI and controls in the following tests: Trail Making A, Logical Memory (Immediate and Delayed recall), Selective Reminding Test (total learning), Visual Reproduction (Immediate and delayed Recall), Boston Naming Test (Naming and Paragnosias), Block Design, and Estimated IQ in which MCI subjects had a worse performance than the elderly Controls. CONCLUSIONS: Our findings suggest that the two groups evaluated through an extensive neuropsychological battery present differences in memory performance but also in other cognitive functions as attention, language and praxis. Perhaps the MCI multiple-domain concept would be more useful than the amnestic MCI considering individuals coming from community samples
122

Apatia e funções executivas em pacientes com doença de Alzheimer leve e em indivíduos com comprometimento cognitivo leve amnéstico / Apathy and executive functions in patients with Alzheimer disease and subjects with amnestic mild cognitive impairment

Guimarães, Henrique Cerqueira 13 February 2012 (has links)
INTRODUÇÃO: A apatia constitui o transtorno neuropsiquiátrico mais prevalente na doença de Alzheimer (DA) e se relaciona com uma série de desfechos deletérios. Sua neurobiologia ainda é pouco compreendida, e alguns autores postulam sua associação com disfunção de circuitos fronto-estriatais. A maior parte da evidência disponível sobre essa relação provém de estudos em que foram avaliados pacientes com DA leve a moderada. OBJETIVO: Investigar a associação entre apatia e disfunção executiva em estágios bastante iniciais do processo de declínio cognitivo no contexto da DA. MÉTODOS: Foram avaliados 87 indivíduos, sendo 28 deles com DA leve, 26 com Comprometimento Cognitivo Leve de subtipo amnéstico (CCLa) e 33 controles. Os participantes foram submetidos a uma bateria de avaliações da qual constavam a Bateria Breve de Rastreio Cognitivo (BBRC-Edu), o Mini-Exame do Estado Mental (MEEM), a Entrevisa Executiva (EXIT-25), a Bateria de Avaliação Frontal (BAF), a Escala de Avaliação de Demência (DRS), o Teste de Aprendizagem Auditivo Verbal de Rey (RAVLT), a Escala de Avaliação de Incapacidade na Demência (DAD) e a Escala de Apatia (EA). Explorou-se correlações entre o desempenho nos testes empregados e os escores aferidos pela EA, nos grupos com comprometimento cognitivo (DA ou CCLa), e em grupos constituídos a partir da combinação deles, considerando os pacientes com CCLa conversores à DA no seguimento. RESULTADOS: O grupo de pacientes com DA apresentava média de idade de 81,9 ± 4,8 anos e escolaridade média de 2,5 ± 2,0 anos. O grupo com CCLa apresentava média de idade de 80,8 ± 3,7 anos e escolaridade média de 3,7 ± 2,8 anos. O grupo dos controles apresentava média de idade de 79,5 ± 3,5 anos e escolaridade média de 3,7 ± 3,3 anos. Os três grupos não se distinguiam significativamente quanto às suas características sociodemográficas. Não foram observadas correlações entre o desempenho em quaisquer dos testes de função executiva empregados e os escores obtidos por meio da EA. Observou-se correlação forte entre o desempenho funcional auferido através da DAD e os escores na EA (rho= -0,7; p<0,001) no grupo DA. Documentou-se correlação moderada entre a sintomatologia apática e o desempenho na subescala Atenção da DRS (rho= -0,59; p<0,01) e em tarefas de evocação tardia nos testes de memória episódica da BBRC (rho=-0,37; p<0,05) e do RAVLT (rho= -0,47; p< 0,001), quando analisados em conjunto os pacientes com DA e aqueles com CCLa que converteram para DA. CONCLUSÃO: Nesta amostra de indivíduos com baixa escolaridade, composta por pacientes com DA leve e CCLa, não se observou associação entre o desempenho em testes de função executiva e a sintomatologia apática medida pela EA / INTRODUCTION: Apathy is the most prevalent neuropsychiatric disorder in Alzheimer disease (AD), and has been related to several deleterious outcomes. Its neurobiology is still poorly understood, and some studies have suggested an association with frontostriatal circuits dysfunction. Most of this evidence comes from studies with mild to moderate AD patients. OBJECTIVE: To investigate the association between apathy and executive dysfunction in the very early stages of cognitive impairment in the context of AD. METHODS: 87 subjects were evaluated, being 28 with mild AD, 26 with amnestic Mild Cognitive Impairment (aMCI) and 33 controls. The participants were submitted to a comprehensively evaluation consisting on the Brief Cognitive Screening Battery (BCSC), the Mini-Mental State Examination (MMSE), the Executive Interview (EXIT-25), the Frontal Assessment Battery (FAB), the Mattis Dementia Rating Scale (DRS), the Rey Auditory Verbal Learning Test (RAVLT), the Disability Assessment in Dementia (DAD), and the Apathy Scale (AS). Correlations were investigated between AS scores and the performance in the cognitive measures within the two cognitively impaired groups (AD or aMCI) and also within combinations of them, considering aMCI convertion to AD. RESULTS: The AD group had mean age of 81.9 ± 4.8 years, and 2.5 ± 2.0 mean years of formal education, while the aMCI group had mean age of 80.8 ± 3.7 years and a mean of 3.7 ± 2.8 years of schooling. Controls were aged 79.5 ± 3.5 years, with 3.7 ± 3.3 years of education. The three groups did not differ statistically from each other regarding the main sociodemographic features. There was no correlation between any executive measure and AS scores. We found strong correlations between AS scores and functional performance evaluated with the DAD (rho= -0.70; p <0.001) in the AD group. There were also modest to moderate correlations between AS scores and DRS Attention subscale (rho= -0.59; p<0.01), and with delayed recall tasks of episodic memory tests from the BCSB (rho=-0.37; p<0.05) and the RAVLT (rho= -0.47 ; p< 0.05), when AD and aMCI converters were analysed toghether as a group. CONCLUSION: In this sample consisting of mild AD and aMCI subjects, with very low educational level, we failed to find any association between executive function tests performance and apathy symptoms measured with the AS
123

Algumas contribuições experimentais ao problema da habilidade inibitória em tarefas com interrupção sinalizada. / Some experimental contributions to the problem of the stopping ability in stop signal tasks.

Sylwan, Rolando Patricio 06 March 2001 (has links)
No presente trabalho é apresentado o Teste de Omissões Voluntárias (Square-Skipping Test, SST), uma versão de papel e lápis da tarefa computadorizada do sinal inibitório. Na primeira parte do trabalho, são relatados estudos que utilizaram uma tarefa computadorizada do sinal inibitório com estímulos excitatórios e inibitórios apresentados visualmente em um procedimento lateralizado. As estratégias de esperar o sinal inibitório foram controladas com sucesso mediante o controle "on-line" da estabilidade dos tempos de reação ao sinal excitatório. Um dos objetivos foi elucidar algum possível fator comum subjacente ao desempenho na tarefa do sinal inibitório e no Teste da tarefa Dupla. Os tempos de reação ao sinal inibitório não foram afetados pela lateralização, enquanto que os tempos de reação ao sinal excitatório direito foram os mais rápidos. Esta vantagem, a qual parece envolver especialização hemisférica e comunicação interhemisférica, correlacionou com a perda no desempenho da tarefa de box-crossing quando combinada com a tarefa verbal no Teste da Tarefa Dupla. A diferença Parte B-menos-Parte A do Trail Making Test correlacionou com os tempos de reação simples. Os resultados também sugerem a associação entre o tempo de reação simples e funções executivas. Foi descartada uma assimetria no sentido do deslocamento da atenção entre hemicampos para explicar a vantagem dos tempos de reação ao sinal excitatório direito. O tempo de reação simples parece ser uma medida de capacidade executiva. A comparação do desempenho de adultos idosos e jovens, medido pela tarefa computadorizada, demostrou que o controle inibitório não foi afetado de forma significativa pela idade. Na segunda parte do trabalho, é apresentado o SST, o qual permite obter de forma prática e rápida, medidas da habilidade inibitória e outras capacidades executivas tais como a flexibilidade cognitiva, a atenção concentrada e a velocidade na busca visual. O SST foi validado mediante a comparação com o desempenho na tarefa computadorizada do sinal inibitório. A execução do SST requer marcar com ‘Xs’ quadradinhos alinhados em um caminho irregular impressos em uma folha A4 (Parte D), sendo que nas Partes A, B e C devem-se omitir alguns quadradinhos indicados. Na terceira tentativa do SST deve ser escrita a seqüência de dígitos ‘1, 2, 3’. A correlação com o teste computadorizado do sinal inibitório sugeriu que o controle inibitório seria medido pela Parte D preenchida com a seqüência de dígitos (Parte D3). A idade não afetou de forma significativa o desempenho na Parte D3. O fator idade parece afetar seletivamente o desempenho nas diferentes partes do SST; p. ex. na Parte A1, que correlacionou com o coeficiente de atenção concentrada do Teste de Toulouse-Pièron. Para evitar os efeitos da prática sobre o desempenho no SST, recomenda-se a execução do Teste da Tarefa Dupla antes da execução do SST, e de preferência na mesma sessão experimental. / The present study aims to contribute to the understanding of the inhibitory ability, within the framework of the neuropsychology. The objective was to develop a paper-and-pencil test to assess the ability to stop an action in a simple and rapid way. A computerized stop signal task was used to validate the test. In the first part of this work, studies that involved the computerized stop signal task are presented. The result of these studies allowed to raise some theoretical issues. The paper-and-pencil test is presented in the second part of this work. In the Experiment 1 the aim was to control experimentally the strategy of waiting for the stop-signal on a lateralized stop signal task, by means of an algorithm, which controlled, on-line, the variation of response latencies for the go-signal (GSRT). Thirty-four healthy volunteers participated in this study. The GRST of the group that performed the task without the algorithm were significantly higher than the GSRT of the group that performed the task with the algorithm, whereas the stop-signal reaction times did not reach significant differences between groups. This procedure provided more stable reaction times throughout the task, and shifted the probability of responding on stop-trials from 0.364 to 0.479. The Experiment 2 studied the relationship between reaction time, laterality, and executive functions were examined by employing two computerized tasks with lateralized visual stimuli. Simple reaction time (SRT) was correlated with the Part B-minus-A difference of Trail Making Test (TMT). No significant difference was found between left and right SRT. Reaction times for left go-signals of the Stop-task were longer than reaction times for right go-signals. The ratio of left go-signal-minus left SRT to right go-signal-minus-right SRT was correlated with the loss in the visuospatial component when it was combined with a concurrent verbal task in the Dual-Task Test. Results suggest association between SRT and executive functions, and the involvement of hemispheric specialization and interhemispheric transfer in both, the stop signal task and the Dual-Tasks Test. Results from Experiment 3 permit to discard the possibility that the observed right visual field advantage observed was due to the orienting of attention across hemifields. The left GSRT were significantly slower than right GSRT. The right GRST advantage was not due to an attentional shift between left and right visual hemifields. In the Experiment 4, the stopping ability of older people in the computerized stop task was explored. There were no significant differences between the stopping ability of older and younger adults. The Square-skipping Test (SST) a paper-an-pencil version of the stop signal computerized task. is described in the second part of this study. The SST is divided in four parts. The effect of the administration of the different parts of the SST was studied in Experiment 5. The results allow for the use of the four parts in the same trial, since there was no effect of order of administration. In Experiment 6 it was studied the effect of placing a digit sequence on the third trial of the test, instead of the X’s. It seems that a greater degree on the inhibitory ability is necessary to perform the task with the sequence "1, 2, 3", than with the sequence "3, 2, 1". Thus, the sequence "1, 2, 3" was used in the final version of the SST. The practice effects of the Dual-Task Test on the SST was studied in Experiment 7. The interaction Group x Trial showed a general decrease on the performance of participants without previous practice in the Dual-task Test, contrasting with the performance of participants with within-session practice, which showed a clear digit sequence load effect. The aim of Experiment 8 was to know possible aging effects in the performance of SST. A general decrease was observed in the performance of older adults compared with performance of young adults; the interaction Group x Trial showed that the slope of the curves were different. The performance in SST is significantly affected by age. Performance in SST correlated with performance in the stop signal and the SRT tasks, respectively. Performance in SST also correlates with TMT, with the visuospatial component of the mu index of the Dual-task and with the attention coefficient of the Toulouse-Pièron Test. The best predictor of the stopping ability was the performance on the Part D with the digit sequence (Part D3). Thus, SST seems to be a useful neuropsychological tool for the assessment of several executive functions, including the stopping ability, mental flexibility, speed for visual search and focused attention.
124

NORMATIVE DATA FOR FOUR NEUROPSYCHOLOGICAL TESTS IN A SAMPLE OF ADULTS WHO ARE ILLITERATE AND FROM LATIN AMERICA

Morlett Paredes, Alejandra 01 January 2018 (has links)
Neuropsychological tests are standardized tasks used to measure psychological functioning that is associated with a particular brain structure. These tests often are used in diagnosing a cognitive deficiency resulting from brain injuries. Currently, there are a limited number of studies that have focused on standardization of neuropsychological tests in Latin America. Therefore, the vast majority of cognitive tests used in the evaluation of patients with brain damage have no normative parameters adjusted to the cultural characteristics of Latinos and Latinas. As a result, neuropsychological diagnoses among this population may be inadequate, and evaluation of rehabilitation program effectiveness limited. The importance of culturally appropriate indices of neurological tests cannot be overstated; of all the problems presented by individuals with brain injuries, cognitive disorders are the leading source of disability for adequate work, family, and social reintegration among this group. There is an urgent need to standardize neuropsychological tests in Latin America, among Latinos in the US and any other regions where neuropsychological test have not been standardized. An important population subgroup in Latin America severely lacking in norms for many neuropsychological tests are those deemed illiterate or unable to read or write. Developing normative data for individuals who are illiterate will allow neuropsychologists to have a more accurate comparison when attempting to diagnose cognitive deficits among this group in Latin America. This dissertation is unique, as no other studies have looked at the normative data and standardization of neuropsychological tests within this population in Latin America.
125

Neuropsychological deficits in Tshivenda speaking children with attention-deficit/hypersensitivity disorder

Mathivha, Mudzunga January 2005 (has links)
Thesis (M.A. (Clinical Psychology)) --University of Limpopo (Turfloop Campus), 2005 / The aim of this study was to establish whether children with Attention-Deficit/Hyperactivity show deficits in cognitive impulsiveness and motor functions, caused by a hypofunctioning dopamine system. A group of 84 primary school children, 42 classified as ADHD and 42 controls, matched for age, gender and SES, with children without ADHD symptomatology, were compared on their performance on neuropsychological tests which test the functions of the cortical areas supplied by two dopamine branches, the meso-cortical and nigrostriatal branches. The battery consisted of the Wisconsin Card Sorting Test, the Grooved Pegboard, and the Maze Coordination Task. The results of the tests were analysed as a function of gender and ADHD-subtypes. In the majority of tests the clinical groups performed worse than the control groups. This was the case for both genders. The Hyperactive/Impulsive and Combined subtypes consistently performed poorer than the other groups. The results indicate that children with ADHD are more impulsive (deficient executive functions) and have poorer motor control than their control counterparts, which may be an indication of dopamine dysfunction.
126

A neuropsychological asessement of adult sex offenders

Deutsher, Megan Mary, deutsher@bigpond.com January 2004 (has links)
There is widespread concern within at least Western cultures of the potential damage that sex offenders may cause to society. The government statistics highlight a frightening pattern of sexual abuse in Australia, with the trend implicating that sexual assault is on the rise and that children are the predominant victims (ABS, 2003b). Specifically, 17,850 reports of sexual assault were recorded in 2002, a 6% increase since 2001. Further to this, there is still no universal agreement as to the extent to which treatment effectively reduces sexual recidivism. Therefore, there is an urgent need for research into this problem behaviour. Research examining the causes of sexual offending has examined a biological hypothesis that sex offenders have functional brain impairment. However, the results of neuropsychological assessments of various sex offender populations are inconsistent and inconclusive. The aim of this study was to investigate the brain function of males convicted and incarcerated for sexual offences against children using neuropsychological assessment. Specifically, it was hypothesised that the sex offenders would show functional impairment in their frontal and temporal lobes. A battery of neuropsychological tests was compiled to assess the functions of these regions including four WAIS-Ill subtests (Arithmetic, Vocabulary, Block Design and Picture Arrangement), Rey Auditory Verbal Learning Test (RAVLT), Rey Complex Figure (RCF), Wisconsin Card Sorting Test (WCST) and the FAS Test. These tests were administered to 25 incarcerated male sex offenders, 25 incarcerated male non-sex offenders and 25 men with no criminal history. Although attempts were made to match these groups on age, level of education and level of intelligence, statistical analyses revealed that there were significant differences between the groups on these variables. These differences were statistically controlled using analyses of covariance (ANCOVAs) and factorial analyses of variance (ANOVA). The results indicated that the sex offenders performed significantly worse than the controls on all neuropsychological tests. However, statistically significant differences were only found between the sex offenders and control group on the immediate recall trials of the RAVLT and RCF. These observed differences did not change when age, level of education and level of intelligence were statistically controlled. It was concluded that there is insufficient evidence from this study to support the hypothesis that sex offenders have functional impairment in their frontal and temporal lobes. However, given the relevance of potential brain impairment to both the biological and social-cognitive perspectives of sexual offending, future research in this field is warranted.
127

Functional imaging studies of executive-attention in humans comparing healthy subjects & patients with neuropsychiatric disorders

Harrison, Benjamin James, habj@unimelb.edu.au January 2006 (has links)
One of the major goals of cognitive neuroscience is to better understand the psychological and neural bases of human executive-attention. Executive or supervisory attention refers to a collection of higher-order cognitive functions whose primary contribution to behavior is to support controlled information processing and action. The capacity to control attention is essential for our adaptive interaction with the environment because it allows flexibility in our responses to ever changing situational contexts and demands. Executive-attention processes therefore play a unique role in shaping the human experience. Use of three-dimensional functional neuroimaging has fast become the empirical standard for investigating how executive-attention is implemented in the human brain. Most recently, emphasis has been placed on the use of these techniques to parse discrete components of a putative neural network relating to action-monitoring and cognitive control processes of the medial and lateral prefrontal cortex. This work has relied heavily on the use of popular experimental paradigms such as the Stroop task and their unique capacity to challenge such processes in humans. These tasks have also been especially useful for conceptualizing the nature of higher-cognitive dysfunction in complex brain disorders such as schizophrenia. The focus of this thesis concerns a novel application of the Stroop paradigm and functional imaging approach to examine executive-attention performance in healthy subjects and patients with schizophrenia and obsessive-compulsive disorder. On one hand, this work aimed to address current ideas on the nature of executive-control mechanisms and how they may be compromised in these two common psychiatric disorders. On the other hand, this work aimed to examine important conceptual and methodological issues associated with functional imaging approaches to the study of higher-cognition and cognitive psychopathology in humans. In line with connectionist models of executive-attention phenomena, the first study in this thesis investigated the effects of task practice on a larger-scale neurocognitive network associated with performance of the Stroop task in healthy subjects. This study involved the use of a novel methodological approach to model physiological covariances or ?functional connectivity? in PET data, which generated previously unseen and interesting insights into the neural basis of Stroop phenomena, whilst complimenting existing ideas on the role of the anterior cingulate and lateral prefrontal cortex in mediating executive-control functions. These findings were then extended to a comparative study of patients with schizophrenia and obsessive-compulsive disorder. This study largely corroborated previous reports of prefrontal executive dysfunction in schizophrenia, although patients also showed evidence for a compensatory strengthening of connectivity in a fronto-parietal network that accompanied task practice. This finding has important implications for existing models of higher-cognitive dysfunction and abnormal brain integration in schizophrenia. For patients with OCD compared to healthy subjects, performance of the Stroop task evoked a pattern of abnormal connectivity among predominantly corticostriatal regions, including a previously reported hyperfunction of the dorsal anterior cingulate cortex. While this latter result has been linked to a specific disturbance of action-monitoring in patients with OCD, the current study suggests that this may map onto a more extensive corticostriatal network abnormality in line with current theoretical models of this illness. One caveat raised in the first study of patients with schizophrenia concerned the effects of illnesschronicity and medication on functional imaging studies of higher-cognition and prefrontal function in schizophrenia. To address this, a second clinical study was undertaken in patients with a first-episode of schizophrenia (diagnosis confirmed at follow-up) who were examined before and after commencing antipsychotic treatment. Overall, the findings from this study support the idea of trait-like disturbances of prefrontal executive function in schizophrenia; however, they also suggested that aspects of this disturbance may be specific to the critical, early stage of illness - implicating progressive changes with illness chronicity and/or treatment intervention. These findings are discussed in relation to the developmental context of cognitive psychopathology in schizophrenia.
128

Executive Function in the Presence of Sleep Disordered Breathing

Sutton, Amy M 12 February 2008 (has links)
The purpose of the study was to investigate whether sleep-disordered breathing (SDB) impairs executive functioning in children. Additionally, the study sought to identify the executive functions at risk in SDB and the contribution of daytime sleepiness. SDB represents a spectrum of upper airway conditions that can be mild, such as snoring, or severe, such as obstructive sleep apnea (OSA). Children with these problems may present with excessive sleepiness, failure to thrive, and a variety of cognitive and behavioral dysfunctions including impaired executive functioning. Beebe and Gozal (2002) developed a theoretical model to explain the impact of sleepiness and hypoxia on executive functioning. This model provided a framework to examine links between the medical disorder and the neuropsychological consequences. Twenty-seven children with suspected SDB were tested with polysomnography (PSG) and a neuropsychological battery. Parents completed subjective measures of cognitive function and sleep symptoms. The children were ages 8 to 18 and had no congenital or acquired brain damage. They were matched for age and gender with 21 healthy controls. The executive function protocol included subtests from the Delis-Kaplan Executive Function System (D-KEFS), the digit span subtest from the Wechsler Intelligence Scale for Children (WISC-IV), the Tower of London-II-Drexel University (TOL-II), the Behavioral Rating Inventory of Executive Functioning (BRIEF), and the Conners’ Continuous Performance Test (CPT-II). Statistical analysis was performed using 2 statistical software packages, SAS and NCSS. Regression analysis was used to evaluate all variables. Due to significant group differences in socio-economic status (SES), SES was included as a covariate, along with IQ. No group differences in IQ were found. Significantly less robust executive function in children with SDB was identified in the domains of cognitive flexibility and impulsivity. Additionally, poorer executive planning and overall inattentiveness was also associated with SDB. Level of significance was set at 0.05 and trends (0.05 < p < 0.10) were acknowledged. Other areas of executive function, including working memory, behavioral and emotional inhibition, and processing speed were not associated with SDB. Moreover, academic functioning was significantly lower in children with SDB, although the differences can be shared equally with SDB, SES and IQ.
129

Alternate forms of knowledge in polysubstance use subgroups /

Ryder, Katherine Ann. January 1999 (has links) (PDF)
Thesis--University of Oklahoma. / Includes bibliographical references (leaves 51-58).
130

Neuropsychological effects of the traumatic stress response in sexually abused adolescents throughout treatment

Wilson, Kathryn R. January 2009 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed January 5, 2010). PDF text: v, 187 p. : ill. ; 807 K. UMI publication number: AAT 3360289. Includes bibliographical references. Also available in microfilm and microfiche formats.

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