The primary aim of this study was to investigate source memory performance in individuals diagnosed with Parkinson's disease (PD). The secondary goal was to explore how memory was impacted when subjects were asked to generate responses during encoding. Fifty idiopathic PD patients and fifty healthy control subjects completed a task measuring item memory and source memory which also included a generation manipulation. Relative to controls, PD patients exhibited deficits in source memory but not item memory. Both groups demonstrated enhanced memory performance in the generative condition of the item memory task. The PD group displayed a marginally significant trend toward improvement in source memory when instructed to generate a response. These findings lend support to the notion of a selective pattern of source memory impairment in PD, highlighted by a dissociation between item and source memory performance. Generative tasks may be related to increased activation of key frontal regions that facilitate memory performance. These results could inform new perspectives for cognitive rehabilitation in PD, although further research is necessary.

L’objectif de la présente étude visait à évaluer les effets différentiels de la privation de sommeil (PS) sur le fonctionnement cognitif sous-tendu par les substrats cérébraux distincts, impliqués dans le réseau fronto-pariétal attentionnel, lors de l’administration d’une tâche simple et de courte durée. Les potentiels évoqués cognitifs, avec sites d’enregistrement multiples, ont été prévilégiés afin d’apprécier les effets de la PS sur l’activité cognitive rapide et ses corrélats topographiques. Le matin suivant une PS totale d’une durée de 24 heures et suivant une nuit de sommeil normale, vingt participants ont exécuté une tâche oddball visuelle à 3 stimuli. L’amplitude et la latence ont été analysées pour la P200 et la N200 à titre d’indices frontaux, tandis que la P300 a été analysée, à titre de composante à contribution à la fois frontale et pariétale. Suite à la PS, une augmentation non spécifique de l’amplitude de la P200 frontale à l’hémisphère gauche, ainsi qu’une perte de latéralisation spécifique à la présentation des stimuli cibles, ont été observées. À l’opposé, l’amplitude de la P300 était réduite de façon prédominante dans la région pariétale pour les stimuli cibles. Enfin, un délai de latence non spécifique pour la N200 et la P300, ainsi qu’une atteinte de la performance (temps de réaction ralentis et nombre d’erreurs plus élevé) ont également été objectivées. Les résultats confirment qu’une PS de durée modérée entraîne une altération des processus attentionnels pouvant être objectivée à la fois par les mesures comportementales et électrophysiologiques. Ces modifications sont présentes à toutes les étapes de traitement, tel que démontré par les effets touchant la P200, la N200 et la P300. Qui plus est, la PS affecte différemment les composantes à prédominance frontale et pariétale. / The objective of the present study was to assess the differential effects of sleep deprivation (SD) on cognitive functions relying on distinct cerebral networks, involved in the fronto-parietal attentional network, during a relatively simple and short cognitive task. Multi-sites recording event-related-potentials (ERP) were used in order to evaluate the effect of SD on rapid cognitive activity and its topographical correlates. The morning following a night of total SD and a night of sleep, 20 participants were administered a 3-stimuli visual oddball paradigm. Amplitudes and latencies of the P200 and N200 ERP components were analyzed as frontal indexes, whereas P300 was analyzed as a mixed frontal and parietal component. Following TSD, a non specific increase in P200 amplitude for the left hemisphere, as well as a loss of lateralisation in response to target stimuli, were observed. Contrarily, P300 amplitude was predominantly reduced in the parietal region in response to target stimuli. Moreover, N200 and P300 latencies were delayed non specific to the type of stimuli and performance (reaction time and accuracy) was altered. These results confirm the deleterious effect of a moderate duration SD on attention processes that can be objectified by means of behavioural and electrophysiological measures. Each stages of information processing was altered by SD, as shown by its effect on P2, N2 and P3 components. Moreover, SD affected differently components caracterized by a predominant frontal or parietal distribution.

In Part I, recall of spatial location was studied in an incidental-learning situation, where patients with unilateral brain lesions, the amnesic patient, H. M., and normal control subjects were asked to estimate the prices of objects in an array. All patient groups could encode location normally, but patients with right temporal-lobe lesions that included extensive hippocampal removal showed abnormally rapid forgetting. For all groups, and for H. M., location-recall did not differ under automatic and under effortful encoding conditions. It is argued that these results point to the importance of hippocampal-ceocortical interactions in spatial memory. In Part II, patients with frontal-lobe lesions were shown to be impaired in judging the frequency with which words or designs occurred in a list. With words, the deficits were demonstrable for both examiner-provided and self-generated stimuli. This impairment may be attributable either to a disorderly search process or to a deficit in cognitive estimation, or both.

This thesis investigated the nature of the deficit in story recall associated with temporal-lobe damage in the left hemisphere dominant for speech. The first three experiments examined whether excision of this region (1) slows the rate at which verbal material is processed, (2) reduces working-memory capacity, or (3) interferes with the integration of information across sentences. Left temporal lobectomy does not impair these aspects of the initial processing of stories, since on none of the above variables was the performance of left temporal-lobe groups deficient relative to that of normal control subjects, or patients with unilateral frontal- or right temporal-lobe removals. The fourth experiment examined the effect of left temporal lobectomy on how quickly a passage was forgotten after it had been learned to criterion. Although patients with such an excision took more trials to learn a story than did normal control subjects, only those patients with extensive left hippocampal removal were impaired when recalling this story 20 minutes later. These results highlight the role of the left hippocampus in the long-term maintenance of story information.

Thesis (Ph.D.)--York University, 2006. Graduate Programme in Psychology. / Typescript. Includes bibliographical references (leaves 148-172). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:NR19801

Thesis (Ph.D.)--City University of New York, 2003. / Includes bibliographical references (leaves 88-98).

Thesis (Ph. D.)--UCLA, 2009. / Vita. Description based on print version record. Includes bibliographical references (leaves 62-80).

Thesis (M.A.)--York University, 2006. Graduate Programme in Psychology. / Typescript. Includes bibliographical references (leaves 66-75). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR29554

Thesis (M.Sc.)--York University, 2008. Graduate Programme in Kinesiology and Health Science. / Typescript. Includes bibliographical references (leaves 69-81). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR51534

Orientador: Vânia Maria de Vasconcelos Machado / Resumo: Há poucos estudos disponíveis sobre a aplicação da ultrassonografia para o diagnóstico de tireopatias em equinos e, até onde sabemos, nenhuma pesquisa foi descrita utilizando a ressonância magnética (RM) para o estudo da glândula tireoide em cavalos. Foi observado em alguns relatos de casos que o lobo tireoidiano hígido serviu de base para a avaliação do lobo contralateral alterado. Entretanto, não existem estudos mostrando a relação entre o lobo tireoidiano esquerdo e direito através de técnicas imaginológicas em equinos. A análise de reprodutibilidade pode ser usada para estimar a variação biológica e metodológica para aprovar o processo de validação dos dados. Inicialmente, este estudo objetivou determinar a confiabilidade das medidas tireoidianas, a partir da comparação entre os lobos tireoidianos esquerdo e direito; bem como avaliar os contornos, formatos, ecotextura e ecogenicidade dos lobos tireoidianos através da ultrassonografia em modo B; quali-quantitativamente caracterizar a vascularização da glândula tireoide equina através da ferramenta Doppler. For fim, este trabalho objetivou, a partir da RM, selecionar as melhores sequências de imagens através da avaliação dos contornos, intensidade e homogeneidade do sinal da glândula tireoide hígida; determinar a confiabilidade das medidas tireoidianas, através da comparação entre os lobos tireoidianos esquerdo e direito; bem como avaliar os contornos, formatos de seus lobos e, por fim, descrever as principais estruturas an... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: There are few studies available on the application of ultrasonography for the diagnosis of equine thyropaties and, to the best of our knowledge, no studies have been reported demonstrating the use of magnetic resonance imaging (MRI) in thyroid evaluation in horses. It was observed in some case reports that the healthy thyroid lobe served as model for the evaluation of the altered contralateral lobe. However, there are no studies showing a positive relation between the left and right lobes by using ultrasonography and MRI in horses. Reproducibility analysis can be used to estimate the biological and methodological variation to approve the data validation process. Initially this study aimed at determining reliably of the thyroid measurements from the comparison between the left and right thyroid lobes, as well as assessing the contour, format, echotexture and echogenicity of the thyroid lobes by mode-B ultrasonography. Additionally, the equine thyroid gland vascularization was quali-quantitatively characterized the by Doppler tool. Finally, through the MRI, this study aimed to select the best imaging sequences by the evaluation the contours, intensity and homogeneity of signal of the normal thyroid; to determinate reliably their measurements from the comparison between the left and right thyroid lobes, as well as assessing the format thyroid lobes and to describe the main anatomical structures of the neck ventroproximal portion. The sample size initially was determined by the a... (Complete abstract click electronic access below) / Doutor