Le présent travail de thèse par articles visait à apporter sa contribution, d’une part à la compréhension des relations entre mouvements oculaires et vieillissement cognitif normal et pathologique, d’autre part à la caractérisation des modifications oculomotrices spécifiques à la maladie d’Alzheimer et à la dépression, deux pathologies parfois cliniquement difficiles à discriminer chez la personne âgée. À travers une série de quatre articles et une expérience non publiée, nous avons examiné les relations entre le déclin des capacités de contrôle cognitif associé au vieillissement normal et les modifications des paramètres des saccades oculaires liées à l’âge. Par ailleurs, nous avons également étudié précisément les caractéristiques de différents paramètres des saccades et leurs liens avec l’altération du contrôle cognitif dans la maladie d’Alzheimer. La comparaison directe des performances oculomotrices de patients atteints de la maladie d’Alzheimer et de patients âgés atteints de dépression a permis de différencier des caractéristiques oculomotrices spécifiques à la maladie d’Alzheimer de celles spécifiques à la dépression du sujet âgé. Enfin, nous avons pu mettre en évidence la spécificité de l’analyse visuelle des informations émotionnelles des visages chez des patients âgés souffrant de dépression.Dans l’ensemble, ces travaux ont montré une influence du déclin cognitif lié à l’âge, mais aussi de la dépression et de la maladie d’Alzheimer sur les performances oculomotrices. Le ralentissement du traitement de l’information semble avoir un impact sur les paramètres des saccades sur toutes les tâches proposées. La latence et le nombre de saccades erronées ont pu être associés aux capacités d’inhibition. Le nombre et le temps de correction des saccades corrigées étaient plutôt liés aux capacités de surveillance (monitoring) et de flexibilité cognitive. Les capacités de correction des saccades erronées dans la dépression étaient similaires à celles du vieillissement normal, mais altérées dans la maladie d’Alzheimer. La latence des saccades était par contre plus influencée par la dépression que par la maladie d’Alzheimer. De plus, le traitement des stimuli émotionnels a révélé des stratégies particulières chez les patients âgés atteints de dépression – un évitement des caractéristiques émotionnelles des visages, excepté pour la joie – qui pourraient être différentes de l’altération de la recherche visuelle retrouvée dans la maladie d’Alzheimer par des études antérieures. Que ce soit au travers des tâches de saccades ou d’exploration visuelle, les mouvements oculaires peuvent refléter les processus de contrôle cognitif et permettre de différencier la dépression de maladie d’Alzheimer. / This doctoral dissertation aimed at better characterizing the relations between eye movements and normal and pathological cognitive ageing on the one hand, and the oculomotor modifications related to Alzheimer's disease and depression – two pathologies sometimes clinically difficult to discriminate in the elderly person — on the other hand. Through a series of five experiments, we examined the relations between the decline of the cognitive control capacities associated with normal ageing and the age-related modifications of the ocular saccade parameters. In addition, we also precisely studied the characteristics of various saccade parameters and their relations with the deterioration of cognitive control, present in the Alzheimer's disease. The direct comparison of the oculomotor performances of patients suffering from the Alzheimer's disease and elderly patients suffering from depression allowed us to differentiate the oculomotor characteristics specific to the Alzheimer's disease from those specific to the depression. Lastly, we highlighted the specificity of the visual process of emotional faces among elderly patients suffering from depression.Globally, this work showed an influence of the cognitive decline related to the age, but also of the depression and Alzheimer's disease on the oculomotor performances. The information processing slowing seems to have an impact on the parameters of all the saccadic tasks. The latency and the number of erroneous saccades were associated with the inhibition capacities. The number and the time of correction of corrected saccades were rather related to the monitoring and flexibility abilities. The capacities of correction of erroneous saccades in depression were similar to those of normal ageing, but impaired in Alzheimer's disease. On the other hand, the saccade latency appears to be more impacted by depression than by Alzheimer's disease. Moreover, the emotional face processing revealed the presence of particular strategies among elderly patients suffering from depression – avoidance of the emotional facial features, except for happy faces – and which could be different from the alteration of the visual search previously found in Alzheimer's disease. Whether it be in saccade tasks or in visual exploration tasks, eye movements can reflect cognitive control and enable us to differentiate depression from Alzheimer’s disease.

A preparação de obras para violão compostas em afinações não tradicionais é comumente considerada uma tarefa complexa. Dependendo da afinação, a disposição das notas ao longo da escala do instrumento pode vir a se alterar radicalmente. Isso interfere diretamente na preparação de uma obra, desde os momentos iniciais da leitura, passando pelo processo de digitação e também de memorização. A presente pesquisa teve como objetivo investigar a eficácia de diferentes estratégias de estudo durante a abordagem inicial de peças para violão com scordaturas não usuais, por oito violonistas de diferentes níveis acadêmicos. Outros objetivos incluem identificar os problemas comuns aos violonistas durante o estudo de obras com scordatura e investigar se a formação prévia exerce influência no aprendizado de obras com afinações não tradicionais. Para a coleta de dados, duas sessões de estudo individuais foram realizadas. Cada sessão consistiu no estudo de trechos musicais, seguido da performance do trecho estudado e de uma entrevista semiestruturada. Foi também aplicado um questionário cujo objetivo era acessar os dados históricos referentes à experiência musical dos Sujeitos. No primeiro encontro, foi permitido aos Sujeitos conduzir o estudo deliberadamente, com o objetivo de prepará-lo no menor tempo possível. No segundo encontro, os Sujeitos receberam estratégias de estudo previamente estabelecidas para cada trecho. As sessões, performances e entrevistas foram filmadas. Os níveis de formação foram determinantes na qualidade dos produtos finais da sessão de estudo deliberado. O uso das quatro estratégias gerou performances com menor diferença qualitativa entre Sujeitos de diferentes níveis acadêmicos. Também, a eficácia destas foi influenciada pela sua adequação à textura e idioma harmônico das peças. As entrevistas e questionários evidenciaram, também, que o perfil de aprendizado de cada Sujeito, no que concerne a sua relação com o estudo, o uso individual de representações mentais, anotação de guias de estudo na partitura, bem como sua trajetória musical, influenciam o modo como diferentes estratégias podem ou não ser eficazes, independentemente do detalhamento da informação que elas disponham na partitura. / The learning of guitar works composed in nontraditional tunings is commonly considered a complex task. Depending on the tuning, the arrangement of notes along the instrument fretboard can change radically. It interferes directly in the preparation of a work from the initial reading moments and through the processes of fingering and memorization. The purpose of this research was to investigate the effectiveness of different study strategies during the initial approach to guitar works with unusual scordaturas by eight guitarists of different academic levels. Other objectives included identifying common problems for guitarists during the study of works with scordatura and investigating whether prior training influences the learning of works with nontraditional tunings. For data collection, two separate meetings were held. Each meeting consisted of a session of study of musical excerpts, followed by the performance of the studied excerpt and a semi-structured interview. A questionnaire was applied with he purpose to access the musical experience of the subjects. In the first meeting, subjects were allowed to conduct the study deliberately, in order to prepare the piece in the shortest time possible. In the second meeting, the subjects received study strategies previously established for each piece. The meetings, performances and interviews were filmed. Different academic levels determined the quality of the final products of the first study session. The use of four strategies generated performances with less qualitative differences between the subjects, regardless of their academic level. Also, the effectiveness of these was influenced by its capacity to fit effectively the texture and harmonic idiom of the pieces. Interviews and questionnaires showed also that the learning profile, the individual use of mental representations, the use of study guides in the score and the musical background of each subject, have influenced how different strategies may or may not be effective, regardless of how much information they provide in the score.

One of the main findings of research on bilingualism in the last twenty years is the fact that both languages are always active, to some extent, and interact with each other. This interaction gives rise to a computationally complex feature of the bilingual mind, namely that the two languages compete with each other. Many studies have addressed the linguistic consequences of this competition (e.g. differences in linguistic attainment), while others have instead addressed the cognitive consequences (e.g. training effects on cognitive control). These two strands of research, when brought together, can shed light on the dynamics of language processing and of its relationship with other cognitive abilities; however, they do not often converge. The first aim of this thesis is to seam them together. The second aim of this thesis is to understand the effects of specific aspects of language experience on linguistic and non linguistic abilities. A critical assumption I make is that bilingualism is not a dichotomous variable, but rather a continuum, characterised by several aspects such as linguistic proficiency, age of acquisition, and daily exposure. All of these factors interact with each other to give rise to potentially infinite types of bilingual experiences, and arguably modulate how bilinguals deal with competing languages. However, the effects of these factors on linguistic and non linguistic abilities are poorly understood. Hence, in this thesis I examine if the bilingual experience affects other cognitive abilities (study 1), how the ability to handle this competition is modulated by experience (study 2), and how it affects language processing (study 3). To examine how specific dimensions of the bilingual continuum affect these abilities, I compare four populations of bilinguals, whose linguistic experience ranges from late bilinguals who are immersed in their native language and are passive users of their second language, to early highly proficient bilinguals who use both languages actively. My first study examines cognitive control performance and shows that high active proficiency and early age of acquisition, together, represent beneficial circumstances for the ability to modulate cognitive control; however, their effects are not strong enough to override individual variability. The second study investigates how the bilingual experience modulates the ability to access the two languages separately, overcoming the competition between them at different levels. This could be at a local level, i.e. the level of the individual linguistic representation (e.g. naming time of a specific word), or at a global or whole language level (e.g. overall naming latencies across languages). The results show that proficiency affects local competition, and age of acquisition affects global competition, whereas daily language exposure regulates competition at both the local and the global levels. My third study examines the processing of pronouns, which are particularly demanding linguistic structures. It shows that active proficiency and age of acquisition, together, define circumstances in which pronoun processing may vary between individuals, independently of structural differences between their languages. This suggests that bilinguals with long-term exposure to more than one language and high active proficiency may use some linguistic structures in the same way as individuals with different linguistic backgrounds, i.e. explicitly interpret them in similar ways, but process them in marginally different ways. Through these studies, this thesis brings together research on linguistic and cognitive aspects of bilingualism by identifying three dimensions of the bilingual experience - proficiency, exposure and age of acquisition - and their effects on language processing, language control and cognitive control.

The aim of the study was to examine the acute effects of exercise on three executivefunctions: attention, inhibition and working memory, in regularly exercising women (​n​ = 10)and men (​n​ = 10). Furthermore, the purpose was to investigate if different intensity levels ofaerobic exercise had an effect on executive functioning. Twenty adults, aged 21-54 years,participated in the study. The participants were randomly assigned to one of two differentexercise intensity levels, moderate or vigorous. Every participant was assigned twoconditions, inactive and active. In both conditions, the participants were exposed to twentyminutes on a stationary bicycle, followed by a 10 minute delay before testing cognitivefunctions. To evaluate executive performance, three cognitive tests were used: the Strooptest, Trail Making Test and Digit span. No significant results were found. Results fromprevious studies, combined with the present study, indicate that the relationship betweenexercise and executive functioning is very complex and needs further research.

Este trabalho teve como objetivo investigar as funções executivas (FE) e alterações do humor em pacientes com doença de Parkinson (DP). O primeiro estudo procurou apresentar uma revisão sistemática da literatura sobre o tema. No artigo seguinte, em um estudo empírico, comparou-se o desempenho das FE e alterações do humor em um grupo de pacientes com DP (N= 40) e um grupo controle (N= 30). O grupo clínico apresentou desempenho significativamente inferior em diversas medidas de avaliação cognitiva, especialmente no instrumento Behavioural Assessment of the Dysexecutive Syndrome (BADS), mas não para as variáveis ansiedade e depressão (p< 0,05). Os resultados demonstram que as alterações das FE e depressão são transtornos frequentes, mesmo em fases iniciais da DP. / This work aimed to investigate the executive functions (EF) and mood changes in patients with Parkinson's disease (PD). The first study sought to present a systematic review of the literature on the subject. In the second, in an empirical study, we compared the performance in EF and mood in a group of PD patients (N = 40) and a control group (N = 30). The clinical group had a significantly poorer performance on several measures of cognitive assessment, especially the BADS, but not for the variables anxiety and depression (p <0.05). The results show that changes in EF are frequent disorders, even in early stages of PD.

Arithmetic abilities are required when solving problems such as “3x4” or “24+33” and are important for many everyday life situations: for instance, to make a recipe or to pay at the store. Given the high incidence of arithmetic difficulties throughout development, the acquisition of arithmetic abilities received much attention in field of numerical cognition. However, although fundamental, only a handful of studies (e.g. Geary & Wiley, 1991) investigated the impact of normal aging on arithmetic problem solving.Therefore the question of whether and how arithmetic abilities are affected by the decline of cognitive processing remains poorly understood. The aim of the current thesis was to fill in this gap and to investigate whether and how arithmetic abilities as well as the related executive functions change when aging. Our results showed that the deficit with age in arithmetic abilities and related executive functions is not general but specific to the executive function under investigation. Moreover, our findings suggest that these executive functions could be specific to the arithmetic domain and not an instance of a more general executive system.In our view, this thesis constitutes an initial step towards enhancing our comprehension of the impact of age on executive functions in the arithmetic domain and its potential specificity with other domains. However, especially because of the lack of studies directly addressing these issues, the results reported here need to be replicated to strengthen our conclusions. In this respect, we believed that the DDM could help to specify exactly which cognitive processes remain intact with age and which become deficient. / Doctorat en Sciences psychologiques et de l'éducation / info:eu-repo/semantics/nonPublished

On estime que plus de la moitié de population mondiale sait parler au moins deux langues et que 40% de cette population bilingue utilise les deux langues au quotidien. Les psycholinguistes et les neuropsycholinguistes se sont rapidement intéressés au fonctionnement du cerveau bilingue et à la façon dont deux langues pouvaient partager un seul cerveau. Ainsi, de nombreuses recherches ont porté sur la représentation de plusieurs langues dans le cerveau ainsi que sur les mécanismes permettant de passer d’une langue à l’autre, mais aussi sur la période développementale sensible à l’apprentissage des langues.Dans ce travail, nous nous sommes intéressés au rôle de l’âge d’acquisition et du niveau de compétence des deux langues sur a) la représentation des substrats cérébraux, b) la plasticité cérébrale et c) la capacité d’alterner entre les deux langues. Pour cela nous comparons des locuteurs bilingues précoces -qui ont appris les deux langues avant 3 ans- et des locuteurs bilingues tardifs -qui ont appris la deuxième langue après 10 ans- tous ayant atteint un très bon niveau de compétence dans les deux langues. Le niveau langagier et le fonctionnement exécutif des participants ont été mesurés à l’aide de plusieurs tâches linguistiques et non linguistiques. Grâce à la technique d’imagerie par résonances magnétiques fonctionnelles (IRMf), nous avons pu identifier les substrats neuronaux des deux langues pour chacun des groupes, les aires impliquées dans le contrôle des langues ainsi que les changements cérébraux dus à l’apprentissage précoce de deux langues. De manière générale, les résultats montrent que la compétence langagière, plutôt que l’âge d’acquisition, aurait un rôle essentiel sur la représentation des langues. En revanche, l’âge d’acquisition serait déterminant en ce qui concerne la structure cérébrale des certaines aires impliquées dans les processus langagiers. / It is estimated that more than half of the world's population speaks two languages and that 40% of the population uses both languages on a daily basis. Psycholinguists and neuropsycholinguists became interested early in the way in which two languages could share a single brain. They have therefore been interested in the representation of several languages in the bilingual brain, in the sensitive period during which languages are learned and also in the mechanisms that allow bilinguals to switch from one language to another without apparent effort. In this work, we investigated the role of the age of acquisition and proficiency of languages and the influence of two languages a) on the representation of cerebral substrates of two languages, b) on the cerebral plasticity, c) and on the mechanisms of language control. For this purpose, we compare early bilingual speakers, who learned both languages before the age of 3 years, and late bilingual speakers who learned the second language after 10 years, both of whom had a very good level of proficiency in both languages. Participants were assessed in a wide range of linguistic and non-linguistic tasks to measure language level and executive functioning. Using the functional magnetic resonance imaging technique, we were able to identify the neuronal substrates of the two languages for each group and the areas involved in language control, as well as cerebral changes due to the early learning of two languages. In general, the results show that language proficiency, rather than the age of acquisition, has an essential role on the representation of languages, but that the age of acquisition is decisive in regards of cerebral structure of certain areas related to language.

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder characterized by difficulty paying attention, impulsivity, and hyperactivity. Diagnosis of ADHD rose 42% from 2003–2004 to 2011–2012. In 2011, 3.5 million children were treated with drugs. Optimizing therapy can take a year, and may not be completely effective. A clinical trial is currently being conducted of a device/drug combination using the computer game Minecraft, to determine how certain activities affect executive function, working memory, and restraint in patients diagnosed with ADHD. The human subjects’ responses are being modeled using artificial neural networks (ANNs), an artificial intelligence method that can be utilized to interpret highly complex data. We propose using ANNs to optimize drug and Minecraft therapy for individual patients based on the initial NICHQ Vanderbilt assessment scores. We are applying ANNs in the development of computational models for executive function deficiencies in ADHD. These models will then be used to develop a therapeutic video game as a drug/device combination with stimulants for the treatment of ADHD symptoms in Fragile X Syndrome. As a first step towards the design of virtual subjects with executive function deficits, computational models of the core executive functions working memory and fluid intelligence were constructed. These models were combined to create healthy control and executive function-deficient virtual subjects, who performed a Time Management task simulation that required the use of their executive functions to complete. The preliminary working memory model utilized a convolutional neural network to identify handwritten digits from the MNIST dataset, and the fluid intelligence model utilized a basic recurrent neural network to produce sequences of integers in the range 1-9 that can be multiplied together to produce the number 12. A simplified Impulsivity function was also included in the virtual subject as a first step towards the future inclusion of the core executive function inhibition.

La plupart des travaux empiriques ont montré que les jeunes et les âgés utilisent de nombreuses stratégies pour accomplir des tâches cognitives. Ils mettent aussi en évidence que les âgés (a) utilisent moins de stratégies, (b) utilisent les stratégies disponibles dans des proportions différentes, (c) exécutent moins efficacement les stratégies utilisées, et (d) choisissent, sur chaque problème, moins fréquemment la meilleure stratégie que les jeunes. L’objectif général de cette thèse était de déterminer quels sont les mécanismes sous-tendant la différence de performances jeunes/âgés dans ces différentes dimensions stratégiques. Nous testons l’hypothèse que le déclin des fonctions exécutives médiatise les différences liées à l’âge dans le répertoire, la distribution, l’exécution et la sélection stratégiques. Pour atteindre cet objectif, nous avons adopté une approche corrélationnelle et une approche expérimentale. Les résultats répliquent les principales données concernant les différences jeunes/âgés dans les différentes dimensions stratégiques. De plus, ils mettent en évidence le rôle essentiel des fonctions exécutives, et, en particulier, de la flexibilité cognitive et de l’inhibition, dans la diminution avec l’âge du répertoire, de la sélection et de l’exécution stratégiques. Nous discutons les implications de ces résultats sur le vieillissement et les variations stratégiques, d’une part, et sur les modèles de la sélection stratégique, d’autre part. / Empirical studies on strategic variations during aging have shown that young andolder adults use multiple strategies to accomplish cognitive tasks. They also showed that older adults (a) use fewer strategies, (b) do not use available strategies with the same frequency as young adults (c) execute strategies less efficiently, and (d) select less frequently the best strategy than young adults. The aim of this study was to investigate which mechanisms underly the strategic differences in young and older adults. We tested the hypothesis that age related decline of executive functions mediate age-related differences in strategy repertoire, distribution, execution, and selection. To achieve these ends, we adopted correlational and experimental approaches. Results replicated previous data relative to differences between young and older adults in different strategy dimensions. Results also highlight crucial role ofexecutive functions, especially cognitive flexibility and inhibition, in strategy repertoire, selection, and execution. Implications for further our understanding of aging and strategic variations, as well as current theoretical models of strategy selection are discussed.

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