Hintergrund Ziel der vorliegenden Untersuchung war die Erfassung der Lebensqualität von älteren Menschen mit leichten kognitiven Störungen im Vergleich zu kognitiv gesunden älteren Menschen. Die Prävalenz von leichten kognitiven Störungen in der Bevölkerung wird in epidemiologischen Studien mit 3 bis 19 % der über 65-Jährigen angegeben (Ritchie, 2004). Methode Es handelt sich um eine 2012 bundesweit durchgeführte bevölkerungsrepräsentative Befragung zur subjektiven Lebensqualität von 997 Probanden (60 Jahre und älter). Die Erfassung erfolgte mittels der Messinstrumente WHOQOL-BREF und dem speziell für ältere Menschen entwickelten WHOQOL-OLD. Zudem wurden die ermittelten Werte für die Lebensqualität in den soziodemografischen Kontext gesetzt, um eventuelle Faktoren zu ermitteln, die die unterschiedlichen Bereiche der Lebensqualität beeinflussen. Zur Identifikation kognitiver Störungen wurde der DemTect eingesetzt. Bei Verdacht auf Demenz fand das Interview nicht statt. Probanden mit leichten kognitiven Beeinträchtigungen wurden interviewt. Das Ergebnis des DemTects bestimmte die Zuteilung der Probanden in die jeweilige Gruppe (leichte kognitive Störungen vs. kognitiv gesund). Die Kriterien für die Gruppe der Probanden mit leichten kognitiven Störungen erfüllten 267 Probanden, für 730 Teilnehmer fanden sich keine Anzeichen einer kognitiven Beeinträchtigung. Ergebnis Die befragten Probanden im Alter ab 60 Jahre mit leichten kognitiven Störungen schätzten ihre Lebensqualität in allen Bereichen des WHOQOL-BREF und WHOQOL-OLD (außer im Bereich Ängste und Befürchtungen hinsichtlich Tod und Sterben) geringer ein als kognitiv gesunde Probanden. Schlussfolgerung Es konnte gezeigt werden, dass bereits leichte kognitive Störungen mit einer erheblichen Reduktion der subjektiven Lebensqualität einhergehen.

Background: Subjective cognitive decline (SCD), i.e., the self-perceived feeling of worsening cognitive function, may be the first notable syndrome of preclinical Alzheimer’s disease and other dementias. However, not all individuals with SCD progress. Stability of SCD, i.e., repeated reports of SCD, could contribute to identify individuals at risk, as stable SCD may more likely reflect the continuous neurodegenerative process of Alzheimer’s and other dementias. Methods: Cox regression analyses were used to assess the association between stability of SCD and progression to MCI and dementia in data derived from the population-based Leipzig Longitudinal Study of the Aged (LEILA75+). Results: Of 453 cognitively unimpaired individuals with a mean age of 80.5 years (SD = 4.2), 139 (30.7 %) reported SCD at baseline. Over the study period (M = 4.8 years, SD = 2.2), 84 (18.5 %) individuals had stable SCD, 195 (43.1 %) unstable SCD and 174 (38.4 %) never reported SCD. Stable SCD was associated with increased risk of progression to MCI and dementia (unadjusted HR = 1.8, 95 % CI = 1.2–2.6; p < .01), whereas unstable SCD yielded a decreased progression risk (unadjusted HR = 0.5, 95 % CI = 0.4–0.7; p < .001) compared to no SCD. When adjusted for baseline cognitive functioning, progression risk in individuals with stable SCD was significantly increased in comparison to individuals with unstable SCD, but not compared to individuals without SCD. Conclusions: Our results, though preliminary, suggest that stable SCD, i.e., repeated reports of SCD, may yield an increased risk of progression to MCI and dementia compared to unstable SCD. Baseline cognitive scores, though within a normal range, seem to be a driver of progression in stable SCD. Future research is warranted to investigate whether stability could hold as a SCD research feature.

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.

La maladie de Parkinson (PD) a été uniquement considérée pour ses endommagements sur les circuits moteurs dans le cerveau. Il est maintenant considéré comme un trouble multisystèmique, avec aspects multiples non moteurs y compris les dommages intérêts pour les circuits cognitifs. La présence d’un trouble léger de la cognition (TCL) de PD a été liée avec des changements structurels de la matière grise, matière blanche ainsi que des changements fonctionnels du cerveau. En particulier, une activité significativement réduite a été observée dans la boucle corticostriatale ‘cognitive’ chez des patients atteints de PD-TCL vs. PD non-TCL en utilisant IRMf. On sait peu de cours de ces modèles fonctionnels au fil du temps. Dans cette étude, nous présentons un suivi longitudinal de 24 patients de PD non démente qui a subi une enquête neuropsychologique, et ont été séparés en deux groupes - avec et sans TCL (TCL n = 11, non-TCL n = 13) en fonction du niveau 2 des recommandations de la Movement Disrders Society pour le diagnostic de PD-TCL. Ensuite, chaque participant a subi une IRMf en effectuant la tâche de Wisconsin pendant deux sessions, 19 mois d'intervalle. Nos résultats longitudinaux montrent qu'au cours de la planification de période de la tâche, les patients PD non-TCL engageant les ressources normales du cortex mais ils ont activé en plus les zones corticales qui sont liés à la prise de décision tel que cortex médial préfrontal (PFC), lobe pariétal et le PFC supérieure, tandis que les PD-TCL ont échoué pour engager ces zones en temps 2. Le striatum n'était pas engagé pour les deux groupes en temps 1 et pour le groupe TCL en temps 2. En outre, les structures médiales du lobe temporal étaient au fil du temps sous recrutés pour TCL et Non-TCL et étaient positivement corrélés avec les scores de MoCA. Le cortex pariétal, PFC antérieur, PFC supérieure et putamen postérieur étaient négativement corrélés avec les scores de MoCA en fil du temps. Ces résultats révèlent une altération fonctionnelle pour l’axe ganglial-thalamo-corticale au début de PD, ainsi que des niveaux différents de participation corticale pendant une déficience cognitive. Cette différence de recrutement corticale des ressources pourrait refléter longitudinalement des circuits déficients distincts de trouble cognitive légère dans PD. / PD was traditionally thought of as purely a movement disorder, now it is considered a multisystem disorder, with multiple non-motor aspects including damages to the cognitive circuits. Mild cognitive impairment (MCI) in PD has been linked with structural gray matter, white matter as well as functional brain changes. Specifically, significantly reduced activity was observed in the ‘cognitive’ corticostriatal loop in patients with PD-MCI vs. PD non-MCI using fMRI. Little is known regarding the course of these functional patterns over time. In this study we present longitudinal follow up of 24 non-demented PD who underwent neuropsychological investigation and were separated in two groups - with and without MCI (MCI n=11, Non-MCI n=13) according to the MDS level 2 recommendation for diagnosis of PD-MCI. Afterwards, each participant underwent an fMRI investigation by performing the Wisconsin Card Sorting Task over two sessions, 19 months apart. Our longitudinal results show that during planning set-shift period of the task, PD Non-MCI patients were engaging the normal cortical resources but they also activated more cortical areas at time 2 that are related to decision-making such as the medial prefrontal cortex (PFC), parietal lobe and the superior PFC, whilst the patients with MCI failed to engage these areas at both time points. The striatum was not engaged for both groups at time 2 and for MCI group at time 1. Furthermore, medial temporal lobe structures (MTLS) were under-recruited overtime for both the MCI and Non-MCI PD patients, and were positively correlated with MoCA scores over time. Parietal cortex, anterior PFC, superior PFC, and posterior putamen were negatively correlated with MoCA scores. These results reveal functional alteration along the basal ganglial-thalamo-cortical axis in early PD, as well as different cortical involvement levels along the course cognitive impairment. This discrepancy in cortical resources recruitment over time might reflect deficient circuitry distinct to cognitive impairment in Parkinson’s disease.

Le processus de vieillissement humain est un processus complexe qui varie grandement d’une personne à l’autre. Malgré l’ampleur des recherches faites sur le sujet, il reste encore beaucoup à explorer et à comprendre. Cette thèse propose trois expériences qui nous permettent d’améliorer notre compréhension des changements qui s’opèrent dans la mémoire de travail visuelle et l’attention visuospatiale avec la prise en âge. La première expérience propose d’examiner les changements dans les capacités de mémoire de travail visuelle entre des jeunes adultes, des adultes âgés sains et des personnes atteintes de trouble cognitif léger (TCL). De plus, grâce à un suivi fait avec les personnes ayant un TCL, nous avons pu examiner si des différences existaient au niveau comportemental entre les âgés qui ont déclinés vers un type de démence et ceux dont l’état est resté stable. Plusieurs techniques peuvent être utilisées pour étudier les effets du vieillissement sur le cerveau. Les tests neuropsychologiques et les tâches comportementales présentées dans la première expérience en sont un exemple. La neuroimagerie peut aussi s’avérer particulièrement utile. En effet, certaines mesures électrophysiologiques, aussi appelées potentiels reliés aux évènements (PRE), sont associées à des fonctions cognitives précises. Ces composantes nous permettent de suivre ces processus et d’observer les modulations causées par les caractéristiques des stimuli ou l’âge par exemple. C’est le cas de la N2pc (négativité 2 postérieure controlatérale) et de la SPCN (sustained posterior contralateral negativity), des composantes électrophysiologiques liées respectivement à l’attention visuospatiale et la mémoire de travail visuelle. On connait bien ces deux composantes ainsi que les facteurs qui les modulent, or elles sont peu utilisées pour les changements qui occurrent dans l’attention et la mémoire de travail visuelle dans le cadre du processus de vieillissement. Les deuxième et troisième expériences proposent d’utiliser une tâche de recherche visuelle (nombre d’items de couleur et identification d’une relation spatiale entre deux items de couleur) afin d’explorer les changements observables sur ces composantes électrophysiologiques. La deuxième expérience examine l’efficacité d’un paradigme à présentations multiples (‘multiple frame’) afin de mesurer la N2pc et la SPCN chez de jeunes adultes. La troisième expérience a pour but d’examiner les effets du vieillissement normal sur l’amplitude et la latence de la N2pc et la SPCN en utilisant le même type de tâche de recherche visuelle. / Human ageing is a complex process that varies a lot from one person to the other. Despite the scope of research of that subject, there is still a lot to explore. This thesis proposes three experiments that will help increase our understanding of the many changes in visual working memory and visuospatial attention seen in ageing. The first experiment assesses the changes in visual working memory capacities between young adults, healthy older adults, and persons with MCI. Furthermore, we were able to do a follow-up with the persons with MCI and determine which ones remained in a stable cognitive state and the ones that decline toward mild dementia, providing us with the opportunity to test for potential behavioral differences allowing us to distinguish between them. Many techniques, such as neuropsychological tests and behavioral tasks, can be used to study the effects of ageing on the brain. Neuroimaging techniques can be particularly useful. In fact, many electrophysiological measures, called event-related potentials (ERPs), are linked to specific cognitive functions which allow us to follow those processes and observe the modulations caused by stimuli characteristics or ageing for example. This is the case of the N2pc (negativity 2 posterior contralateral) and the SPCN (sustained posterior contralateral negativity), two ERPs linked to visuospatial attention and visual working memory. While they are both well-known in the literature, not many studies are using them as a way to examine the changes appearing in the visuospatial attention and the visual working memory during the normal ageing process. The second and third experiment use a visual search task (including 2 conditions: counting the number of items presented and identify a specific spatial relation between 2 coloured items) to explore the changes seen on those ERPs. The second experiment wants to assess the efficiency of a multiple frame paradigm to measure the N2pc and the SPCN with young adults. The third experiment wants to examine the effects of normal ageing on the amplitude and the latency of the two components using the same type of visual search task.

Introduction : La prise de décision (PD), les fonctions exécutives et l’apathie ont des processusneuropsychologiques et des substrats neuro-anatomiques communs. Tous trois sont altérés dans lamaladie d’Alzheimer (MA) mais aussi dans le Trouble Léger de la Cognition (TLC). Par ailleurs, ladéficience décisionnelle peut affecter l’autonomie.Méthode : Afin d’évaluer les corrélats exécutifs cognitifs et comportementaux de la PD, nous avonscomparé 20 sujets contrôles (CT), 20 patients ayant un TLC et 20 patients MA.Outre le MMSE et l’échelle de Beck (dépression), tous ont complété 3 épreuves exécutives liées aumodèle de Miyake (évaluant la flexibilité, l’inhibition et la mémoire de travail), 2 échelles d’apathie,une échelle de compétence (autonomie) et 2 tâches décisionnelles (sous ambiguïté et sous risque).3 études ont été finalisées : (1) Fonctions exécutives et PD, (2) Apathie et PD, (3) PD et autonomie.Résultats : Il existe une relative comparabilité des patients TLC et MA, inférieurs aux sujets CT, dupoint de vue de la PD, des fonctions exécutives, de l’apathie et de l’autonomie. La PD sous risqueimplique directement les fonctions exécutives et est associée à la composante cognitive de l’apathie,alors que celle sous ambiguïté les implique indirectement et est associée à la composantecomportementale de l’apathie. Il y a un effet équivalent de chacune des modalités décisionnelles surl’autonomie.Conclusion : La PD dans la MA et le TLC semble d’abord altérée par des facteurs exécutifs cognitifs,dont l’expression varie suivant la modalité décisionnelle. Les implications théoriques, cliniques et lavalidité écologique de ces outils d’évaluation sont discutées. / Introduction : Decision making (DM), executive functions and apathy have commonneuropsychological processes and neuroanatomical substrates. The three of them are impaired in theAlzheimer disease (AD) but also in the Mild Cognitive Impairment (MCI). Besides, decision deficitcan impair autonomy.Method : In order to estimate the behavioral and cognitive executive correlates of DM, we havecompared 20 Control subjects (CT), 20 patients with MCI and 20 patients with AD.In addition with the MMSE and the Beck Inventory (depression), all have performed 3 executive testslinked to the Miyake model (estimating flexibility, inhibition and working memory), two apathyscales, one competency scale (autonomy) and two decision tasks (under ambiguity and under risk).Three studies have been completed : (1) Executive functions and DM, (2) Apathy and DM, (3) DMand autonomy.Results : there is a relative comparability between MCI and AD patients, below CT subjects,regarding DM, executive functions, apathy and autonomy.DM under risk directly implies the executive functions and is associated with the cognitive componentof apathy, whereas DM under ambiguity implies them indirectly and is associated with the behavioralcomponent of apathy. There is a similar impact of both decision modes on autonomy.Conclusion : DM in AD and MCI seems first to be impaired by cognitive executive factors, whoseform varies according to the decision model. The theoretical, clinical involvements and the ecologicalvalidity of these evaluation tools are challenged.

This diploma thesis deals with the topic of Subjective memory complaints (SMC) in elderly population in relation to early diagnostics of Alzheimer's Disease (AD). The term of SMC describes patients with subjective perception of cognitive impairment which is not objectivized during a complex neuropsychological assessment. The character of their subjective complaints has not been thoroughly examined, despite their increased risk to develop cognitive impairment, most likely due to AD (Reisberg, et al., 2008). The aim of this cross-sectional study was to verify the clinical significance of the concept of SMC and to characterize subjective complaints in SMC in comparison to patients with cognitive deficit at the stage of amnestic mild cognitive impairment (aMCI) and in comparison to cognitively healthy elderly (HE). SMC and aMCI patients did not differ in the amount of subjective complaints, but SMC patients reported significantly more complaints compared to HE. The difference in the amount of complaints reported by the patients themselves and by their informants was found neither in aMCI, nor in SMC patients. There were identified questions which may distinguish between SMC and aMCI patients, and questions which may distinguish between SMC patients and HE; that means questions able to distinguish...

Patients with amnestic type of mild cognitive impairment (aMCI) are diagnosed mainly on the basis of performance in verbal memory tests. This thesis deals with the use of a nonverbal test called the Brief Visuospatial Memory Test-Revised (BVMT-R) for the diagnosis of mild cognitive impairment (MCI). This research compared the performance of patients with clinical diagnosis of MCI (N=79) using the BVMT-R with the performance of these patients using the Auditory Verbal Learning Test (AVLT), the AVLT being a validated instrument for differentiating aMCI patients from healthy control patients. Both tests follow a similar design paradigm, but they differ in the type of stimuli measured: the BVMT-R tests memory for nonverbal material and the AVLT tests for verbal material. Results showed that there is a moderate correlation between scores (total score, delayed recall score) of the BVMT-R and equivalent scores of the AVLT. Further analyses of performance of MCI patients in both tests (in total scores and delayed recall scores) identified that there was a proportion of patients tested using the BVMT-R with memory impairment that did not show any memory impairment using the AVLT. Our findings indicate a favorable diagnostic potential of BVMT-R in the diagnostics of mild cognitive impairment. Keywords:...

The thesis discusses screening psychodiagnostics with special attention given to amnestic mild cognitive impairment and Alzheimer's disease. The theoretical part describes the concepts of healthy aging and the disorders of cognitive functions. It provides an overview of the screening methods most frequently used in the Czech Republic and the description of MoCA test. It also briefly outlines the issues of retesting in psychodiagnostics. The objective of the empirical part of the work was to verify the psychometric characteristics of the Czech alternative version MoCA-CZ and to evaluate whether it is possible to use this test in practice. The evaluation also includes a comparison of the new version with the already established standard version of MoCA-CZ test. We assigned standard and alternative versions of MoCA-CZ in a 2-month interval to 59 healthy volunteers, 35 patients with mild cognitive impairment and 41 patients with dementia resulting from Alzheimer's disease. We found a strong correlation between alternative and standard version of MoCA-CZ test. We confirmed statistically significant differences in the average scores between individual research groups in both versions of the test. We proved that the alternative version MoCA-CZ 2 is reliable. And we demonstrated that the administration and...

Aumento das concentrações de cortisol em idosos com Doença de Alzheimer (DA) tem sido relatado como resultado da ausência de inibição do eixo hipotálamo-pituitária-adrenal (HPA) em decorrência da disfunção hipocampal observada nestes indivíduos. Além disso, associação entre concentrações elevadas de cortisol e comprometimento da memória tem sido evidenciada em idosos saudáveis. Entretanto, pouco se sabe a respeito do envolvimento do estresse nas concentrações de cortisol, no desempenho cognitivo e nas estratégias de coping tanto em idosos saudáveis como naqueles com comprometimento cognitivo leve (CCL) e DA. Assim, este estudo teve o objetivo de investigar a associação entre intensidade de estresse, concentrações de cortisol, estratégias de coping e desempenho cognitivo em idosos saudáveis, com CCL e DA. Para isto, concentrações basais de cortisol salivar foram analisadas em uma amostra composta por 40 idosos saudáveis, 31 idosos com CCL amnéstico e 40 indivíduos com DA leve. O desempenho cognitivo global foi avaliado a partir do mini-exame do estado mental (MEEM), o desempenho da memória através da Bateria Breve de Avaliação Cognitiva (BBAC) e pelo teste de extensão de dígitos na ordem inversa. A intensidade do estresse foi avaliada a partir da Lista de Sintomas de Stress (LSS) e as estratégias de coping através da Escala de Coping de Jalowiec (ECJ). Desta forma, foram observadas concentrações de cortisol marginalmente mais elevadas nos idosos com DA do que nos idosos saudáveis (p = 0.062). Além disso, verificou-se associação positiva entre cortisol e desempenho da memória nos idosos saudáveis (p = 0.008), enquanto correlação negativa entre estas variáveis foi observada no grupo CCL (p = 0.011). Não foi verificada associação significativa nos idosos com DA (p > 0.05). Ademais, observou-se correlação positiva entre as concentrações de cortisol e a intensidade de estresse somente nos idosos com CCL (p = 0.056). Com relação às estratégias de enfrentamento, observou-se que os idosos com CCL que elegem o coping focado no problema apresentam intensidade de estresse menor que os idosos que utilizam o coping focado na emoção (p = 0.048). Estes resultados sugerem que a associação entre concentrações de cortisol, desempenho da memória, intensidade de estresse e coping varia em função da presença ou ausência de comprometimento cognitivo e da percepção das limitações cognitivas / Increased cortisol levels have been reported in elderly with Alzheimers disease (AD) as a result of the lack in the hypothalamic-pituitary-adrenal (HPA) axis inhibition as a function of hipocampal atrophy observed in those subjects. Moreover, association between high cortisol levels and memory impairment has been demonstrated in healthy elderly subjects. However, little is known about the stress involvement in the cortisol levels, in the cognitive performance and in the coping strategies in both elderly with mild cognitive impairment (MCI) and with AD. Thus, this study aimed to investigate the association between stress intensity, cortisol levels, coping strategies and cognitive performance in healthy elderly, subjects with CCL and with DA. Basal salivary cortisol was measured in a sample composed of 40 healthy elderly subjects, 31 individuals with amnestic MCI and 40 subjects with mild AD. Global cognitive performance was evaluated with the Mini Mental State Exam (MMSE) and memory performance was assessed with the Brief Cognitive Screening Battery (BCSB) and the backward digit span test. Stress intensity was evaluated with the Stress Symptoms List (SSL) and coping strategies with the Jalowiec Coping Scale (JCS). Marginally higher cortisol levels were observed in the subjects with AD group in comparison with healthy elderly (p = 0.062). Furthermore, positive association between cortisol levels and memory performance was observed in the healthy elderly (p = 0.008) while negative correlation was observed between these variables in the MCI group (p = 0.011). No significant association was exhibited in the AD group (p > 0.05). Moreover, positive correlation between cortisol levels and stress intensity was observed only in the MCI group (p = 0.056). Regarding the coping strategies, it was observed that those MCI subjects who elect problem focused coping exhibit higher stress intensity than those MCI who use emotion focused coping (p = 0.048). These results suggest the association between cortisol levels, memory performance, stress intensity and coping strategies may vary as a function of the presence or absence of cognitive impairment and as a function of the cognitive deficits awareness