578 resultados para Habiletés visuo-spatiales


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Hepatitis C is one of the most common chronic infectious diseases worldwide, with well-documented extra-hepatic manifestations, such as a broad number of cognitive deficits. These impairments may be explained by psychiatric comorbidities, which have not been investigated properly in the literature. In order to elucidate a specific hepatitis C virus (HCV) induced cognitive impairment not related to mental disorders, neuropsychological performance of patients infected with HCV was compared with that of patients infected with hepatitis B virus cognitive impairment, especially psychiatric comorbidities. A total of 33 patients infected with HCV and 22 patients infected with HBV were included in the study. There were no significant differences between the two groups with regard to age or years of education. The group of patients infected with HCV performed significantly worse on visuo-spatial memory tasks after adjusting for years of education and age. There were no significant differences between patients infected with HCV and patients infected with HBV with regards to other neuropsychological functions. The data indicate that patients infected with HCV patients have poorer visuo-spacial memory performance than patients infected with HBV, suggesting that the cognitive deficit may be specific to HCV infection and not to secondary comorbid psychiatric disorders. J. Med. Virol. 81: 1184-1188, 2009. (C) 2009 Wiley-Liss, Inc.

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XVII Colóquio AFIRSE/AIPELF: A escola e o mundo do trabalho, Faculdade de Psicologia e de Ciências da Educação da Universidade de Lisboa, 12, 13 e 14 de Fevereiro de 2009.

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Notre étude présente une réflexion à propos de espaces musicaux composables. Cette réflexion inclue l’usage intentionnel des qualités sonores perçues dans la construction de sons et donc dans la composition musicale. Nos recherches se trouvent à l’intersection entre le son, comme phénomène physique qui se propage dans un espace, les sensations spatiales qui peuvent être engendrées par la perception auditive de ses certaines caractéristiques, et la pratique de la composition musicale d’espaces de sons dans les œuvres. Nous développons l’idée d’une entité sonore composable dès sa microstructure. Nous la concevons par analogie avec les objets du monde visible et palpable. Nous utilisons les idées de volume, forme et matière ainsi que celles de position et de mouvement des objets matériels, comme métaphore pour concevoir des entités sonores complexes et des espaces musicaux composés dans lesquels elles seront intégrées. Cette entité sonore constituée d’un ensemble d’éléments disparates, permet le développement de réseaux opératoires manipulables dans, la pratique, par les compositeurs.

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La réalisation de cet entretien avec François Bayle a eu comme objectif premier d'approfondir la compréhension de sa conception du sonore. Le concept d’image de son (i-son) est évidemment l’élément central de sa pensée à propos du sonore. Nous l’avons approché en tant qu’élément présent dans l’espace et perçu par l’oreille. François Bayle nous présente le son en tant que présence porteuse de dimensions spatiales multiples. Il nous montre également que l’intentionnalité de l’écoute est un des éléments déterminants dans la perception des sons dans l’espace. Le compositeur rappelle enfin que les représentations mentales sont construites et que les images sonores de la musique sont composées.

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RESUMO: pela contracção involuntária de grupos musculares de extensão variável, originando movimentos involuntários e posturas anómalas, por vezes dolorosas. O tratamento convencional consiste em injecções localizadas de toxina botulínica, podendo, em casos refractários, estar indicado o tratamento por estimulação cerebral profunda. A neurobiologia da distonia focal primária permanece incompletamente compreendida. Os estudos de neuro-imagem estrutural e funcional revelam alterações subtis da anatomia e funcionamento do estriado e das vias cortico-basais, com destaque para o aumento do volume, da actividade metabólica e da neuroplasticidade do putamen e de áreas corticais motoras, pré-motoras e sensitivas. O conjunto destas alterações aponta para uma disrupção da regulação inibitória de programas motores automáticos sustentados pelo estriado e pelas vias ortico-subcorticais. Nos últimos anos tem crescido o interesse pelas manifestações psiquiátricas e cognitivas da distonia (estas últimas muito pouco estudadas). Tem despertado particular interesse a possível associação entre distonia focal primária e perturbação obsessivo-compulsiva (POC), cuja neurobiologia parece notavelmente sobreponível à da distonia primária. Com efeito, os estudos de neuro-imagem estrutural e funcional na POC revelam consistentemente aumento do volume e actividade do estriado e do córtex órbito-frontal, apontando mais uma vez para uma disfunção do controlo inibitório, no estriado, de programas comportamentais e cognitivos automáticos. Objectivos: 1. Explorar a prevalência e intensidade de psicopatologia em geral, e de psicopatologia obsessivo-compulsiva em particular, numa amostra de indivíduos com distonia focal primária; 2. Explorar a ocorrência, natureza e intensidade de alterações do funcionamento cognitivo numa amostra de indivíduos com distonia focal primária; 3. Investigar a associação entre a gravidade da distonia focal, a intensidade da psicopatologia, e a intensidade das alterações cognitivas. Metodologia: Estudo de tipo transversal, caso-controlo, observacional e descritivo, com objectivos puramente exploratórios. Casos: 45 indivíduos com distonia focal primária (15 casos de blefaroespasmo, 15 de cãibra do escrivão, 15 de distonia cervical espasmódica), recrutados através da Associação Portuguesa de Distonia. Critérios de inclusão: idade = 18; distonia focal primária pura (excluindo casos de distonia psicogénica possível ou provável de acordo com os critérios de Fahn e Williams); Metabolismo do cobre e Ressonância Magnética Nuclear sem alterações. Controlos doentes: 46 casos consecutivos recrutados a partir da consulta externa do Hospital Egas Moniz: 15 doentes com espasmo hemifacial, 14 com espondilartropatia cervical, 17 com síndrome do canal cárpico. Controlos saudáveis: 30 voluntários. Critérios de exclusão para todos os grupos: Mini-Mental State Examination patológico, tratamento actual com anti-colinérgicos, antipsicóticos, inibidores selectivos da recaptação da serotonina, antidepressivos tri- ou tetracíclicos. Avaliação: Avaliação neurológica: história e exame médico e neurológico completos. Cotação da gravidade da distonia com a Unified Dystonia Rating Scale. Avaliação psicopatológica: Symptom Check-List-90-Revised; entrevista psiquiátrica de 60 minutos incluindo a Mini-International Neuropsychiatric Interview (MINI), versão 4.4 (validada em Português), complementada com os módulos da MINI Plus versão 5.0.0 para depressão ao longo da vida e dependência/ abuso do álcool e outras substâncias ao longo da vida; Yale-Brown Obsessive-Compulsive Symptom Checklist e a Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). Avaliação neuropsicológica: Wisconsin Card Sorting Test (WCST; flexibilidade cognitiva); Teste de Stroop (inibição de resposta); Block Assembly Test (capacidade visuo-construtiva); Teste de Retenção Visual de Benton (memória de trabalho visuo-espacial). Análise estatística:os dados foram analisados com a aplicação informática SPSS for Windows, versão 13. Para a comparação de proporções utilizaram-se o teste do Chi-quadrado e o teste de Fisher. Para a comparação de variáveis quantitativas entre dois grupos utilizou-se o teste t de Student ou o teste U de Mann-Whitney (teste de Wilcoxon no caso de amostras emparelhadas). Para comparações de médias entre três grupos recorreu-se à Análise de Variância a um factor (variáveis de intervalo e de rácio), ou ao teste de Kruskal-Wallis (variáveis ordinais). Para o estudo da associação entre variáveis foram utilizados os coeficientes de correlação de Pearson ou de Spearman, a análise de correlações canónicas, a análise de trajectórias e a regressão logística. Adoptou-se um Alpha de 0.05. Resultados: Os doentes com distonia focal primária apresentaram uma pontuação média na Y- -BOCS significativamente superior à dos dois grupos de controlo. Em 24.4% dos doentes com distonia a pontuação na Y-BOCS foi superior a 16. Estes doentes eram predominantemente mulheres, tinham uma maior duração média da doença e referiam predominantemente sintomas obsessivo-compulsivos (SOC) de contaminação e lavagem. Os dois grupos com doença crónica apresentaram pontuações médias superiores às dos indivíduos saudáveis nas escalas de ansiedade, somatização e psicopatologia geral. Os doentes com distonia tratados com toxina botulínica apresentaram pontuações inferiores às dos doentes não tratados nas escalas de ansiedade generalizada, fobia, somatização e depressão, mas não na Y-BOCS. Sessenta por cento dos doentes com distonia apresentavam pelo menos um diagnóstico psiquiátrico actual ou pregresso. O risco de apresentar um diagnóstico psiquiátrico actual era menor nos doentes tratados com toxina botulínica, aumentando com a gravidade da doença. A prevalência de POC foi 8,3% e a de depressão major 37,7%. No WCST e na Prova de Benton, os doentes com distonia focal primária demonstraram um desempenho inferior ao de ambos os grupos de controlo, cometendo sobretudo erros perseverativos. Os doentes com distonia e pontuação na Y-BOCS > 16 cometeram mais erros e respostas perseverativas no WCST do que os restantes doentes com distonia. As análises de correlações e de trajectórias revelaram que nos doentes com distonia a gravidade da distonia foi, juntamente com a idade e a escolaridade, o factor que mais interagiu com o desempenho cognitivo. Discussão: o nosso estudo é o primeiro a descrever, nos mesmos doentes com distonia focal primária, SOC significativos e alterações cognitivas. Os nossos resultados confirmam a hipótese de uma associação clínica específica entre distonia focal primária e psicopatologia obsessivo-compulsiva. Confirmam igualmente que a distonia focal primária está associada a um maior risco de desenvolver morbilidade psiquiátrica ansiosa e depressiva. O tratamento com toxina botulínica reduz este risco, mas não influencia os SOC. Entre os doentes com distonia, os que têm SOC significativos poderão diconstituir um grupo particular com maior duração da doença (mas não uma maior gravidade), predomínio do sexo feminino e predomínio de SOC de contaminação e limpeza. Em termos cognitivos, os indivíduos com distonia focal primária apresentam défices significativos de flexibilidade cognitiva (particularmente acentuados nos doentes com SOC significativos) e de memória de trabalho visuo-espacial. Estes últimos devem-se essencialmente a um défice executivo e não a uma incapacidade visuo-construtiva ou visuo-perceptiva. A disfunção cognitiva não é explicável pela psicopatologia depressiva nem pela incapacidade motora, já que os controlos com doença periférica crónica tiveram um desempenho superior ao dos doentes com distonia. No seu conjunto os nossos resultados sugerem que os SOC que ocorrem na distonia focal primária constituem uma das manifestações clínicas da neurobiologia desta doença do movimento. O predomínio de sintomas relacionados com higiene e o perfil disexecutivo de alterações cognitivas–perseveração e dificuldades executivas de memória de trabalho visuo-espacial – apontam para a via cortico-basal dorso-lateral e para as áreas corticais que lhe estão associadas como estando implicadas na tripla associação entre sintomas motores, obsessivo-compulsivos e cognitivos. Conclusões: A distonia focal primária é um síndrome neuropsiquiátrico complexo com importantes manifestações não motoras, nomeadamente compromisso cognitivo do tipo disexecutivo e sintomas obsessivo-compulsivos. Clinicamente estas manifestações representam necessidades de tratamento que vão muito para além da simples incapacidade motora, devendo ser activamente exploradas e tratadas.-------------- ABSTRACT: Introduction: primary focal dystonia is an idiopathic movement disorder that manifests as involuntary, sustained contraction of muscular groups, leading to abnormal and often painful postures of the affected body part. Treatment is symptomatic, usually with local intramuscular injections of botulinum toxin. The neurobiology of primary focal dystonia remains unclear. Structural and functional neuroimaging studies have revealed subtle changes in striatal and cortical-basal pathway anatomy and function. The most consistent findings involve increased volume and metabolic activity of the putamen and of motor, pre-motor and somato-sensitive cortical areas. As a whole, these changes have been interpreted as reflecting a failure of striatal inhibitory control over automatic motor programs sustained by cortical-basal pathways. The last years have witnessed an increasing interest for the possible non-motor – mainly psychiatric and cognitive – manifestations of primary focal dystonia. The possible association of primary focal dystonia with obsessive-compulsive disorder (OCD) has raised particular interest. The neurobiology of the two disorders has indeed remarkable similarities: structural and functional neuroimaging studies in OCD have revealed increased volume and metabolic activity of the striatum and orbital-frontal cortex, again pointing to a disruption of inhibitory control of automatic cognitive and behavioural programs by the striatum. Objectives: 1. To explore the prevalence and severity of psychopathology – with a special emphasis on obsessive-compulsive symptoms (OCS) – in a sample of patients with primary focal dystonia;2. To explore the nature and severity of possible cognitive dysfunction in a sample of patients with primary focal dystonia; 3. To explore the possible association between dystonia severity, psychiatric symptom severity, and cognitive performance, in a sample of patients with primary focal dystonia. Methods: cross-sectional, case-control, descriptive study. Cases: forty-five consecutive, primary pure focal dystonia patients recruited from the Portuguese Dystonia Association case register (fifteen patients with blepharospasm, 15 with cervical dystonia and 15 with writer’s cramp). Inclusion criteria were: age = 18; primary pure focal, late-onset dystonia (excluding possible or probable psychogenic dystonia according to the Fahn & Williams criteria); normal copper metabolism and Magnetic Resonance Imaging. Diseased controls: forty-six consecutive subjects from our hospital case register (15 patients with hemi-facial spasm; 14 with cervical spondilarthropathy and cervical spinal root compression; 17 with carpal tunnel syndrome). Healthy controls were 30 volunteers.Exclusion criteria for all groups: Mini-Mental State Examination score below the validated cut-off for the Portuguese population (<23 for education between 1 and 11 years; <28 for education >11 years); use of anti-cholinergics, neuroleptics, selective serotonin reuptake inhibitors, triciclic or tetraciclic antidepressants. Assessment: neurological assessment: complete medical and neurological history and physical examination; dystonia severity scoring with the Unified Dystonia Rating Scale. Psychiatric assessment:Symptom Check-List-90-Revised; 60 minute-long psychiatric interview, including Mini-International Neuropsychiatric Interview (MINI), version 4.4 (validated Portuguese version), extended with the sections for life-time major depressive disorder and life-time alcohol and substance abuse disorder from MINI-Plus version 5.0.0; Yale-Brown Obsessive-Compulsive Symptom Checklist and Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). Cognitive assessment: Wisconsin Card Sorting Test (WCST; cognitive set-shifting ability); Stroop Test (response inhibition); Block Assembly Test(visual-constructive ability); Benton’s Visual Retention Test (visual-spatial working memory). Statistic analysis: Data were analyzed with SPSS for Windows version 13. Proportions were compared using Chi-Square test, or Fisher’s exact test when appropriate. Student’s t-test or Mann-Whitney’s U test (or Wilcoxon’s teste in the case of matched samples) were used for two-group comparisons. P-values were corrected for multiple comparisons. One-way ANOVA with Bonferroni post-hoc analysis (interval data), or the Kruskal-Wallis Test (ordinal data), were used for three-group comparisons. Associations were analysed with Pearson’s or Spearman’s correlation coefficients, canonical correlations, path analysis and logistic regression analysis. Alpha was set at 0.05. Results: Dystonia patients had higher Yale-Brown Obsessive-Compulsive Symptom scores than both control groups. 24.4% of primary dystonia patients had a Y-BOCS score > 16. These patients were predominantly women; they had longer disease duration, and showed a predominance of hygiene-related OCS. The two groups with chronic disease had higher anxiety, somatization and global psychopathology scores than healthy subjects. Primary dystonia patients undergoing treatment with botulinum toxin had lower anxiety, phobia, somatization and depression scores than their untreated counterparts, but similar Y-BOCS scores. Sixty percent of primary dystonia patients had at least one lifetime psychiatric diagnosis. The odds of having a currently active psychiatric diagnosis were lower in botulinum toxin treated patients, and increased with dystonia severity. The prevalence of OCD was 6.7%, and the lifetime prevalence of major depression was 37.7%. Primary dystonia patients had a lower performance than the two control groups in both the WCST and Benton’s Visual Retention Test, mainly due to an excess of perseveration errors. Primary dystonia patients with Y-BOCS score > 16 had much higher perseveration error and perseveration response scores than dystonia patients with Y-BOCS = 16. Correlation and path analysis showed that, in the primary dystonia group, dystonia severity, along with age and education, was the main factor influencing cognitive performance. Discussion: our study is the first description ever of concomitant significant OCS and cognitive impairment in primary dystonia patients. Our results confirm that primary dystonia is specifically associated with obsessive-compulsive psychopathology. They also confirm that primary focal dystonia patients are at a higher risk of developing anxious and depressive psychiatric morbidity. Treatment with botulinum toxin decreases this risk, but does not influence OCS. Primary focal dystonia patients with significant OCS may constitute a particular subgroup. They are predominantly women, with higher disease duration (but not severity) and a predominance of hygiene related OCS.In terms of cognitive performance, primary focal dystonia patients have significant deficits involving set-shifting ability and visual-spatial working memory. The latter result from an essentially executive deficit, rather than from a primary visual-constructive apraxia or perceptual deficit. Furthermore, cognitive flexibility difficulties were more prominent in the subset of primary dystonia patients with significant OCS. The cognitive dysfunction found in dystonia patients is not attributable to depressive psychopathology or motor disability, as their performance was significantly lower than that of similarly impaired diseased controls. Our results suggest that OCS in primary focal dystonia are a direct, primary manifestation of the motor disorder’s neurobiology. The predominance of hygiene-related symptoms and the disexecutive pattern of cognitive impairment – set-shifting and visual-spatial working memory deficits – suggest that the dorsal-lateral cortical-basal pathway may play a decisive role in the triple association of motor dysfunction, OCS and cognitive impairment. Conclusions: primary focal dystonia is a complex neuropsychiatric syndrome with significant non- -motor manifestations, namely cognitive executive deficits and obsessive-compulsive symptoms.Clinically, our results show that PFD patients may have needs for care that extend far beyond a merely motor disability and must be actively searched for and treated.

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Ce texte essaie d’interpréter les relations qui s’établissent entre les processus de construction/négociation des identités culturelles et les processus de touristification de l’espace des villes. Les dynamiques culturelles associées au tourisme intègrent des représentations dont la forme convoque, très souvent, les concepts d’authenticité et d’hyperréalité. L’espace des villes devenues des pôles touristiques est lui aussi souvent marqué par ces deux formes culturelles. C’est, comme ce texte essaie de le montrer, le cas de Macao : le Centre Historique (« Patrimoine Mondial »), un réseau de musées (une vingtaine) et un réseau de casinos (une trentaine) constituent les éléments soumis à cette logique de production de l’espace urbain. Les formes culturelles en question – formulées, dans la théorie, comme deux formes indépendantes (et même incompatibles) – coexistent ici dans une réalité culturelle et urbaine complexe et très instable. Son interprétation exige des formes d’abordages nouvelles qui convoquent – en même temps - plusieurs échelles spatiales.

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Ce texte présente une partie des résultats d’une recherche dont le terrain est constitué par trois localités – une ville (Guimarães), un village (Vizela) et un bourg (Santa Eulália). Notre étude porte sur les représentations de l’espace, que l’on considère comme partie des composantes culturelles qui intègrent les processus de constitution des identités collectives. Les configurations spatiales qui correspondent aux représentations de chaque communauté sont présentes dans les processus de négociation spatial que les trois localités établissent entre elles, en vue de la constitution d’un espace d’ensemble compatible. L’identité de chacune dépend donc de la forme que prend l’espace régional qui comprend les trois localités étudiées. L’étude de cas (Vizela) démontre, dans une situation de transformation du territoire, qu’une double contrainte, organisée par l’inclusion et l’exclusion, conduit à la projection d’un nouvel espace - d’inclusion spatiale, sociale et symbolique - qui constitue une nouvelle réponse à l’imbrication des espaces organisés par différentes villes. Le refus d’une inclusion régionale conduit à la création/revendication d’un nouveau découpage spatial, défini à une échelle plus restreinte, et ce processus se transforme en un point de fixation identitaire.

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RESUMO: Os circuitos fronto-estriatais constituem um sistema em ansa fechada que une diversas regiões do lobo frontal aos gânglios da base, participando, com outras áreas cerebrais, no controlo do movimento, cognição e comportamento. As Distonias Primárias, a Doença de Parkinson e a Hidrocefalia de Pressão Normal, são doenças do movimento caracterizadas por disfunção do circuito fronto-estriatal motor. A conectividade funcional entre as diversas ansas do sistema fronto-estriatal, permite prever que as doenças do movimento possam também acompanhar-se de sintomas da esfera cognitiva e comportamental, cuja avaliação seria importante no manejo diagnóstico e terapêutico dos doentes. Objectivos Os nossos objectivos foram avaliar, por estudos clínicos, a relação entre sintomas motores, cognitivos e comportamentais em três doenças do movimento com fisiopatologias diversas - distonias Primárias, Doença de Parkinson e Hidrocefalia de Pressão Normal - analisando os dados sob a perspectiva teórica fornecida pelo conhecimentos dos vários circuitos frontoestriatais. Os nossos objectivos específicos para cada doença foram: a) Distonias Primárias: avaliação de disfunção executiva em doentes com Distonia Primária e relação com a gravidade dos sintomas motores b) Doença de Parkinson: 1. avaliação breve das funções mentais nas fases iniciais da doença, incluindo análise longitudinal para determinação de factores preditivos para declínio cognitivo; 2. relação entre a função motora e cognitiva e a Perturbação do Comportamento do sono REM, incluindo análise longitudinal; 3.avaliação de sintomas psiquiátricos, de um ponto de vista global e especificamente com incidência sobre as Perturbações do Controlo do Impulso (PCI). c) Hidrocefalia de Pressão Normal: 1. caracterização das alterações da marcha, incluindo comparação com a Doença de Parkinson; 2. caracterização das alterações cognitivas e da relação entre estas e a disfunção da marcha; 3. estudo evolutivo das alterações da marcha e cognitiva em doentes submetido a cirurgia e doentes não submetidos a cirurgia. Métodos: A Distonia Primária, a Doença de Parkinson e a Hidrocefalia de Pressão Normal foram diagnosticadas segundo critérios clínicos validados. Sempre que justificado, foram recrutados grupos de controlo, com indivíduos sem doença, emparelhados para idade, sexo e grau de escolaridade. Os doentes foram avaliados com instrumentos de aplicação clinica directa, incluindo escalas de função motora, testes neuropsicológicos globais e dirigidos às funções executivas e escalas de avaliação psiquiátrica. Testes aplicados nas Distonias Primárias: Unified Dystonia Rating Scale, Wisconsin Card Sorting Test, teste de Stroop, teste de cubos da WAIS, Teste de Retenção Visual de Benton; na Doença de Parkinson: Unified Parkinson's Disease Rating Scale, Frontal Assessment Battery (FAB), Mini-Mental State Examination (MMSE), REM-sleep behaviour disorder Questionnaire; Symptom Chek-list 90-R, Brief Psychiatric Rating Scale, FAS (fluência verbal lexical) Nomeação de Animais (Fluência verbal semântica), prova de repetição de dígitos (WAIS), Rey auditory verbal learning test, teste de Stroop, matrizes progressivas de Raven, Questionnaire for Impulsive-Compulsive Disorders; na HPN: prova cronometrada de marcha,MMSE, prova de memória imediata da WAIS, prova de repetição de dígitos (WAIS), FAB, desenho complexo de Rey, teste de Stroop, cancelamento de letras, teste Grooved Pegboard. Os doentes com HPN foram também submetidos a estudo imagiológico. A avaliação estatística foi adaptada às características de cada um dos estudos.Resultados Distonias Primárias: encontrámos défices de função executiva, envolvendo dificuldade na mudança entre sets cognitivos, bem como correlação significativa entre as pontuações nos testes cronometrados e a gravidade dos sintomas motores. Doença de Parkinson: os doentes com DP obtiveram pontuações significativamente inferiores na FAB e em sub-testes do MMSE (memória e função visuo-espacial). A pontuação no MMSE encontrava-se significativamente correlacionada com itens da função motora não relacionados com o tremor. A disfunção da marcha, a disartria, o fenótipo não tremorígeno, a presença de alucinações e pontuação abaixo do ponto de corte na MMSE, foram factores preditivos de demência na avaliação longitudinal. A rigidez e a disartria foram factores preditivos de declínio nas funções frontais. A disfunção frontal foi factor preditivo de declínio na pontuação do MMSE. Encontrámos uma prevalência elevada de RBD nas fases iniciais da DP, que o estudo longitudinal mostrou ser factor preditivo de declínio motor, nomeadamente por agravamento da bradicinésia. Encontrámos também uma prevalência elevada de sintomas psiquiátricos, nomeadamente psicose, depressão, ansiedade, somatização e sintomas obsessivo-compulsivos. As PCI não se encontravam relacionadas com o fenótipo motor, com as complicações motoras do tratamento dopaminérgico ou com a disfunção cognitiva. HPN: os doentes com HPN e os DP apresentaram um padrão disfunção da marcha semelhante, caraterizado por passos curtos, lentidão e dificuldades de equilíbrio, sendo os sintomas mais graves na HPN. Os doentes de Parkinson com maior duração de doença, maior dose de dopaminérgicos e fenótipo motor acinético-rígido apresentaram um padrão de disfunção da marcha de gravidade semelhante ao encontrado na HPN. As alterações vasculares da substância branca, em particular as encontradas na região frontal, encontravam-se negativamente correlacionadas com a melhoria da marcha após PL. O estudo das funções cognitivas mostrou um padrão de atingimento global, com valores mais baixos na cópia do desenho complexo de Rey. Os resultados nas provas de função cognitiva não se encontravam significativamente correlacionados com os resultados na prova da marcha. A progressão na disfunção da marcha encontrava-se relacionada com o tratamento não cirúrgico, idade superior na primeira avaliação, presença de lesões da substância branca, e presença de factores de risco vascular, ao passo que não foram encontrados factores que predissessem de modo significativo o agravamento da função cognitiva. Conclusões: Os resultados dos diversos estudos, evidenciam a presença de alterações cognitivas e comportamentais nas três doenças de movimento. O padrão destas alterações e o modo como estas se relacionaram com os sintomas motores variou de doença para doença. Nas Distonias primárias, a perseveração cognitiva poderá ser o sintoma correspondente à perseveração motora própria da doença, sugerindo disfunção no circuito dorso-lateral frontoestriatal. A correlação entre a gravidade motora da doença e o resultado nos testes cognitivos cronometrados, poderá ser o efeito da relação entre bradicinésia e bradifrenia. Na Doença de Parkinson, o espectro de alterações é mais acentuado, espelhando a disseminação do processo degenerativo no SNC. Para além dos sintomas de disfunção executiva, sugerindo disfunção das tês ansas não motoras, existem sinais de disfunção cognitiva global, estas com uma influência mais significativa no desenvolvimento da demência. A relação entre os diferentes sintomas motores e cognitivos é também complexa, embora se evidencie uma dissociação significativa entre o tremor, sem relação com os sintomas não motores, e os sintomas motores não tremorígenos, relacionados com o declínio cognitivo. Enquanto que a presença de RBD parece ser um factor preditivo de agravamento motor, os sintomas psiquiátricos, também muito frequentes, apresentam uma relação menos clara com a função motora. Destes, os sintomas obsessivo-compulsivos são aqueles que com mais frequência se atribuem a disfunção do sistema fronto-estriatal, nomeadamente da ansa orbito-frontal. As PCI também não mostraram ter relação com os sintomas motores ou cognitivos. Na HPN, é patente o carácter fronto-estriatal das alterações da marcha, demonstrado tanto na sua caracterização quanto no efeito deletério das lesões vasculares da substância branca do lobo frontal na recuperação da marcha após PL. As alterações cognitivas parecem ter um padrão mais difuso, o que talvez explique a falta de correlação com os sintomas motores - esta dissociação pode ser causada quer por diferença nos mecanismos fisiopatológicos quer por presença de comorbilidades cognitivas. --------- ABSTRACT: Fronto-striatal circuits constitute a closed loop system which connects different parts of the frontal lobes to the basal ganglia. They are engaged in motor, cognitive and behavioural control. Primary Dystonia, Parkinson's Disease and Normal-Pressure Hydrocephalus are movement disorders caused by disturbance of the motor fronto-striatal circuit. The existence of cognitive and behavioural dysfunction in these movement disorders is predictable, given the functional connectivity between the several distinct loops of the circuit. Evaluation of cognitive and behavioural dysfunction in these three disorders is thus both of clinical and theoretical relevance. Objectives Our objectives were to evaluate, by clinical means, the relation between motor, cognitive and behavioural symptoms in three movement disorders with different pathophysiological backgrounds - Primary Dystonia, Parkinson's Disease and Normal-Pressure Hydrocephalus - and to analyse the study results under the theoretical framework formed by present knowledge of the fronto-estriatal system. Specific objectives: a) Primary Dystonia: executive dysfunction assessment and correlation analysis with motor dysfunction severity; b) Parkinson's Disease: 1. brief cognitive assessment in the early stages of disease, including a longitudinal analysis for determination of predictive factors for cognitive decline; 2. to investigate the relation between RBD and cognitive and motor dysfunction, including a longitudinal analysis; 3. psychiatric symptom assessment, with particular incidence on Impulse Control Disorders; c) Normal-Pressure Hydrocephalus: 1. gait dysfunction characterization and comparison with Parkinson's Disease patients; 2. determination of cognitive dysfunction profile and its relation with gait dysfunction; 3. follow-up study of cognitive and motor outcome in patients submitted and not submitted to shunt surgery. Methods: Primary Dystonia, Parkinson's Disease and Normal Pressure Hydrocephalus were diagnosed according to clinically validate criteria. Where warranted, we recruited control groups formed by healthy individuals, matched for age, sex and educational level. Patients were evaluated with instruments of direct clinical application, including motor function scales, neuropsychological tests aimed at global and executive functions and psychiatric rating scales. Tests used in Primary Dystonia: Unified Dystonia Rating Scale, Wisconsin Card Sorting Test, Stroop Test, Cube Assembly test (WAIS), Benton’s Visual Retention Test; in Parkinson's Disease: Unified Parkinson's Disease Rating Scale, Frontal Assessment Battery (FAB) , Mini-mental State Examination (MMSE), REM-sleep behavior disorder Questionnaire, Symptom Check-list 90- R, Brief Psychiatric Rating Scale, FAS (phonetic verbal fluency), semantic verbal fluency test, digit span test (WAIS), auditory verbal learning test,Stroop test, Raven's progressive Matrices, Questionnaire for Impulsive-Compulsive Disorders; in NPH: timed walking test, MMSE, immediate memory task (WAIS), digit span test (WAIS), FAB, Rey’s Complex Figure test, Stroop test, letter cancellation test, Perdue Pegboard test. NPH patients were also subjected to an imaging study. Statistics were adapted to the characteristics of each study.Results: Primary Dystonia: we found set-shifting deficits as well as significant correlation between timed neuropsychological tests and dystonia severity. Parkinson's Disease: PD patients had significantly lower scores on the FAB and on the memory and visuo-spatial tests of the MMSE; MMSE scores were significantly correlated to non-tremor motor scores; gait dysfunction and speech scores, non-tremor motor phenotype, hallucinations and scores bellow cut-off on the MMSE were predictive of dementia at follow-up; speech and rigidity scores were predictive of frontal type decline; frontal dysfunction was predictivy of decline in MMSE scores; RBD bradykinesia worsening; psychiatric symptoms were prevalent, particularly Psychosis, Depression, Anxiety, Somatisation and Obsessive-Compulsive Symptoms; Impulse Control Disorders were unrelated to motor phenotype,motor side effects of dopamine treatment and executive function; NPH: gait dysfunction was worse in NPH when compared to PD patients, although the pattern was similarly characterized by slowness, short steps and disequilibrium; PD patients whose gait disturbance was as severe as that of NPH patients were characterized by longer disease duration, predominance of non-tremor motor scores, more advanced disease stage and higher dopamine dose; frontal white matter lesions correlated negatively with improvement after LP; cognitive function assessment revealed wide spread deficits, with lower results on the drawing of the complex figure of Rey, which were not significantly correlated to gait dysfunction; older age, white matter lesions and the presence of vascular risk factors were predictive factors for motor but not cognitive function worsening. Conclusion: Results from our studies highlight the presence of cognitive and behavioural dysfunction in all three movement disorders. Symptom pattern and the relation with ovement derangement varied according to the disease. In Primary Dystonia, set-shifting difficulties could be the cognitive counterpart of motor perseveration characteristic of this disorder, suggesting dysfunction of the dorso-lateral circuit. The relation between timed tests and dystonia severity could suggest a relation between bradyphrenia and bradykinesia in Primary Dystonia. In Parkinson's Disease patients, the spectrum of non-motor symptoms is wider, probably reflecting the spread of neurodegeneration beyond the fronto-striatal circuits. While frontal type deficits predominate, suggestive of dorso-lateral and orbito-frontal dysfunction, non-frontal deficits were also apparent in the initial stages of disease, and were predictive of dementia at follow-up. The relationship between cognitive and motor symptoms is complex, although the results strongly suggest a dissociation between tremor symptoms, which bore no relation with non-motor symptoms, and non-tremor symptoms,whichwas frequent, and a predictive factor for which were related with cognitive decline. While RBD was found to be a predictive factor for bradykinesia worsening, psychiatric symptoms, which were also frequent, showed no apparent relation with motor dysfunction. Relevant to our theoretical consideration was the high prevalence of OCS, which have been attributed to orbito-frontal dysfunction. As to the particular case of ICD, we found no relation either with motor or cognitive dysfunction. The fronto-striatal nature of gait dysfunction in NPH is suggest by the clinical characterization study and by the effects of frontal white matter lesions on gait recovery after LP, whereas cognitive dysfunction presented a more diffuse pattern, which could explain the lack or relation with gait assessment results and also the different outcome on the longitudinal study - this dissociation could be caused by a real difference in pathophysiological mechanisms or, in alternative, be due to the existence of cognitive comorbidities.

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Tese de Doutoramento em Psicologia (Especialidade de Psicologia Clínica)

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Tese de Doutoramento em Ciências - Especialidade em Física

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Les déficits auditifs spatiaux se produisent fréquemment après une lésion hémisphérique ; un précédent case report suggérait que la capacité explicite à reconnaître des positions sonores, comme dans la localisation des sons, peut être atteinte alors que l'utilisation implicite d'indices sonores pour la reconnaissance d'objets sonores dans un environnement bruyant reste préservée. En testant systématiquement des patients avec lésion hémisphérique inaugurale, nous avons montré que (1) l'utilisation explicite et/ou implicite des indices sonores peut être perturbée ; (2) la dissociation entre l'atteinte de l'utilisation explicite des indices sonores versus une préservation de l'utilisation implicite de ces indices est assez fréquente ; et (3) différents types de déficits dans la localisation des sons peuvent être associés avec une utilisation implicite préservée de ces indices sonores. Conceptuellement, la dissociation entre l'utilisation explicite et implicite de ces indices sonores peut illustrer la dichotomie des deux voies du système auditif. Nos résultats parlent en faveur d'une évaluation systématique des fonctions auditives spatiales dans un contexte clinique, surtout quand l'adaptation à un environnement sonore est en jeu. De plus, des études systématiques sont nécessaires afin de mettre en lien les troubles de l'utilisation explicite versus implicite de ces indices sonores avec les difficultés à effectuer les activités de la vie quotidienne, afin d'élaborer des stratégies de réhabilitation appropriées et afin de s'assurer jusqu'à quel point l'utilisation explicite et implicite des indices spatiaux peut être rééduquée à la suite d'un dommage cérébral.

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In the context of an autologous cell transplantation study, a unilateral biopsy of cortical tissue was surgically performed from the right dorsolateral prefrontal cortex (dlPFC) in two intact adult macaque monkeys (dlPFC lesioned group), together with the implantation of a chronic chamber providing access to the left motor cortex. Three other monkeys were subjected to the same chronic chamber implantation, but without dlPFC biopsy (control group). All monkeys were initially trained to perform sequential manual dexterity tasks, requiring precision grip. The motor performance and the prehension's sequence (temporal order to grasp pellets from different spatial locations) were analysed for each hand. Following the surgery, transient and moderate deficits of manual dexterity per se occurred in both groups, indicating that they were not due to the dlPFC lesion (most likely related to the recording chamber implantation and/or general anaesthesia/medication). In contrast, changes of motor habit were observed for the sequential order of grasping in the two monkeys with dlPFC lesion only. The changes were more prominent in the monkey subjected to the largest lesion, supporting the notion of a specific effect of the dlPFC lesion on the motor habit of the monkeys. These observations are reminiscent of previous studies using conditional tasks with delay that have proposed a specialization of the dlPFC for visuo-spatial working memory, except that this is in a different context of "free-will", non-conditional manual dexterity task, without a component of working memory.

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Abstract (English)General backgroundMultisensory stimuli are easier to recognize, can improve learning and a processed faster compared to unisensory ones. As such, the ability an organism has to extract and synthesize relevant sensory inputs across multiple sensory modalities shapes his perception of and interaction with the environment. A major question in the scientific field is how the brain extracts and fuses relevant information to create a unified perceptual representation (but also how it segregates unrelated information). This fusion between the senses has been termed "multisensory integration", a notion that derives from seminal animal single-cell studies performed in the superior colliculus, a subcortical structure shown to create a multisensory output differing from the sum of its unisensory inputs. At the cortical level, integration of multisensory information is traditionally deferred to higher classical associative cortical regions within the frontal, temporal and parietal lobes, after extensive processing within the sensory-specific and segregated pathways. However, many anatomical, electrophysiological and neuroimaging findings now speak for multisensory convergence and interactions as a distributed process beginning much earlier than previously appreciated and within the initial stages of sensory processing.The work presented in this thesis is aimed at studying the neural basis and mechanisms of how the human brain combines sensory information between the senses of hearing and touch. Early latency non-linear auditory-somatosensory neural response interactions have been repeatedly observed in humans and non-human primates. Whether these early, low-level interactions are directly influencing behavioral outcomes remains an open question as they have been observed under diverse experimental circumstances such as anesthesia, passive stimulation, as well as speeded reaction time tasks. Under laboratory settings, it has been demonstrated that simple reaction times to auditory-somatosensory stimuli are facilitated over their unisensory counterparts both when delivered to the same spatial location or not, suggesting that audi- tory-somatosensory integration must occur in cerebral regions with large-scale spatial representations. However experiments that required the spatial processing of the stimuli have observed effects limited to spatially aligned conditions or varying depending on which body part was stimulated. Whether those divergences stem from task requirements and/or the need for spatial processing has not been firmly established.Hypotheses and experimental resultsIn a first study, we hypothesized that auditory-somatosensory early non-linear multisensory neural response interactions are relevant to behavior. Performing a median split according to reaction time of a subset of behavioral and electroencephalographic data, we found that the earliest non-linear multisensory interactions measured within the EEG signal (i.e. between 40-83ms post-stimulus onset) were specific to fast reaction times indicating a direct correlation of early neural response interactions and behavior.In a second study, we hypothesized that the relevance of spatial information for task performance has an impact on behavioral measures of auditory-somatosensory integration. Across two psychophysical experiments we show that facilitated detection occurs even when attending to spatial information, with no modulation according to spatial alignment of the stimuli. On the other hand, discrimination performance with probes, quantified using sensitivity (d'), is impaired following multisensory trials in general and significantly more so following misaligned multisensory trials.In a third study, we hypothesized that behavioral improvements might vary depending which body part is stimulated. Preliminary results suggest a possible dissociation between behavioral improvements andERPs. RTs to multisensory stimuli were modulated by space only in the case when somatosensory stimuli were delivered to the neck whereas multisensory ERPs were modulated by spatial alignment for both types of somatosensory stimuli.ConclusionThis thesis provides insight into the functional role played by early, low-level multisensory interac-tions. Combining psychophysics and electrical neuroimaging techniques we demonstrate the behavioral re-levance of early and low-level interactions in the normal human system. Moreover, we show that these early interactions are hermetic to top-down influences on spatial processing suggesting their occurrence within cerebral regions having access to large-scale spatial representations. We finally highlight specific interactions between auditory space and somatosensory stimulation on different body parts. Gaining an in-depth understanding of how multisensory integration normally operates is of central importance as it will ultimately permit us to consider how the impaired brain could benefit from rehabilitation with multisensory stimula-Abstract (French)Background théoriqueDes stimuli multisensoriels sont plus faciles à reconnaître, peuvent améliorer l'apprentissage et sont traités plus rapidement comparé à des stimuli unisensoriels. Ainsi, la capacité qu'un organisme possède à extraire et à synthétiser avec ses différentes modalités sensorielles des inputs sensoriels pertinents, façonne sa perception et son interaction avec l'environnement. Une question majeure dans le domaine scientifique est comment le cerveau parvient à extraire et à fusionner des stimuli pour créer une représentation percep- tuelle cohérente (mais aussi comment il isole les stimuli sans rapport). Cette fusion entre les sens est appelée "intégration multisensorielle", une notion qui provient de travaux effectués dans le colliculus supérieur chez l'animal, une structure sous-corticale possédant des neurones produisant une sortie multisensorielle différant de la somme des entrées unisensorielles. Traditionnellement, l'intégration d'informations multisen- sorielles au niveau cortical est considérée comme se produisant tardivement dans les aires associatives supérieures dans les lobes frontaux, temporaux et pariétaux, suite à un traitement extensif au sein de régions unisensorielles primaires. Cependant, plusieurs découvertes anatomiques, électrophysiologiques et de neuroimageries remettent en question ce postulat, suggérant l'existence d'une convergence et d'interactions multisensorielles précoces.Les travaux présentés dans cette thèse sont destinés à mieux comprendre les bases neuronales et les mécanismes impliqués dans la combinaison d'informations sensorielles entre les sens de l'audition et du toucher chez l'homme. Des interactions neuronales non-linéaires précoces audio-somatosensorielles ont été observées à maintes reprises chez l'homme et le singe dans des circonstances aussi variées que sous anes- thésie, avec stimulation passive, et lors de tâches nécessitant un comportement (une détection simple de stimuli, par exemple). Ainsi, le rôle fonctionnel joué par ces interactions à une étape du traitement de l'information si précoce demeure une question ouverte. Il a également été démontré que les temps de réaction en réponse à des stimuli audio-somatosensoriels sont facilités par rapport à leurs homologues unisensoriels indépendamment de leur position spatiale. Ce résultat suggère que l'intégration audio- somatosensorielle se produit dans des régions cérébrales possédant des représentations spatiales à large échelle. Cependant, des expériences qui ont exigé un traitement spatial des stimuli ont produits des effets limités à des conditions où les stimuli multisensoriels étaient, alignés dans l'espace ou encore comme pouvant varier selon la partie de corps stimulée. Il n'a pas été établi à ce jour si ces divergences pourraient être dues aux contraintes liées à la tâche et/ou à la nécessité d'un traitement de l'information spatiale.Hypothèse et résultats expérimentauxDans une première étude, nous avons émis l'hypothèse que les interactions audio- somatosensorielles précoces sont pertinentes pour le comportement. En effectuant un partage des temps de réaction par rapport à la médiane d'un sous-ensemble de données comportementales et électroencépha- lographiques, nous avons constaté que les interactions multisensorielles qui se produisent à des latences précoces (entre 40-83ms) sont spécifique aux temps de réaction rapides indiquant une corrélation directe entre ces interactions neuronales précoces et le comportement.Dans une deuxième étude, nous avons émis l'hypothèse que si l'information spatiale devient perti-nente pour la tâche, elle pourrait exercer une influence sur des mesures comportementales de l'intégration audio-somatosensorielles. Dans deux expériences psychophysiques, nous montrons que même si les participants prêtent attention à l'information spatiale, une facilitation de la détection se produit et ce toujours indépendamment de la configuration spatiale des stimuli. Cependant, la performance de discrimination, quantifiée à l'aide d'un index de sensibilité (d') est altérée suite aux essais multisensoriels en général et de manière plus significative pour les essais multisensoriels non-alignés dans l'espace.Dans une troisième étude, nous avons émis l'hypothèse que des améliorations comportementales pourraient différer selon la partie du corps qui est stimulée (la main vs. la nuque). Des résultats préliminaires suggèrent une dissociation possible entre une facilitation comportementale et les potentiels évoqués. Les temps de réactions étaient influencés par la configuration spatiale uniquement dans le cas ou les stimuli somatosensoriels étaient sur la nuque alors que les potentiels évoqués étaient modulés par l'alignement spatial pour les deux types de stimuli somatosensorielles.ConclusionCette thèse apporte des éléments nouveaux concernant le rôle fonctionnel joué par les interactions multisensorielles précoces de bas niveau. En combinant la psychophysique et la neuroimagerie électrique, nous démontrons la pertinence comportementale des ces interactions dans le système humain normal. Par ailleurs, nous montrons que ces interactions précoces sont hermétiques aux influences dites «top-down» sur le traitement spatial suggérant leur occurrence dans des régions cérébrales ayant accès à des représentations spatiales de grande échelle. Nous soulignons enfin des interactions spécifiques entre l'espace auditif et la stimulation somatosensorielle sur différentes parties du corps. Approfondir la connaissance concernant les bases neuronales et les mécanismes impliqués dans l'intégration multisensorielle dans le système normale est d'une importance centrale car elle permettra d'examiner et de mieux comprendre comment le cerveau déficient pourrait bénéficier d'une réhabilitation avec la stimulation multisensorielle.

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Detection and discrimination of visuospatial input involve at least extracting, selecting and encoding relevant information and decision-making processes allowing selecting a response. These two operations are altered, respectively, by attentional mechanisms that change discrimination capacities, and by beliefs concerning the likelihood of uncertain events. Information processing is tuned by the attentional level that acts like a filter on perception, while decision-making processes are weighed by subjective probability of risk. In addition, it has been shown that anxiety could affect the detection of unexpected events through the modification of the level of arousal. Consequently, purpose of this study concerns whether and how decision-making and brain dynamics are affected by anxiety. To investigate these questions, the performance of women with either a high (12) or a low (12) STAI-T (State-Trait Anxiety Inventory, Spielberger, 1983) was examined in a decision-making visuospatial task where subjects have to recognize a target visual pattern from non-target patterns. The target pattern was a schematic image of furniture arranged in such a way as to give the impression of a living room. Non-target patterns were created by either the compression or the dilatation of the distances between objects. Target and non-target patterns were always presented in the same configuration. Preliminary behavioral results show no group difference in reaction time. In addition, visuo-spatial abilities were analyzed trough the signal detection theory for quantifying perceptual decisions in the presence of uncertainty (Green and Swets, 1966). This theory treats detection of a stimulus as a decision-making process determined by the nature of the stimulus and cognitive factors. Astonishingly, no difference in d' (corresponding to the distance between means of the distributions) and c (corresponds to the likelihood ratio) indexes was observed. Comparison of Event-related potentials (ERP) reveals that brain dynamics differ according to anxiety. It shows differences in component latencies, particularly a delay in anxious subjects over posterior electrode sites. However, these differences are compensated during later components by shorter latencies in anxious subjects compared to non-anxious one. These inverted effects seem indicate that the absence of difference in reaction time rely on a compensation of attentional level that tunes cortical activation in anxious subjects, but they have to hammer away to maintain performance.