Le Trouble de Stress Post-Traumatique (TSPT) est une pathologie fréquente, touchant près de 8 % de la population générale. Cette pathologie psychiatrique s’exprime par un carré symptomatique incluant un syndrome de répétition, d’évitement, une hyperactivation neurovégétative ainsi qu’une altération négative des cognitions et de l’humeur. Un des traitements les plus efficaces dans cette pathologie est une psychothérapie nommée EMDR pour Eye Movement Desensitization and Reprocessing. Bien que cette thérapie ne soit plus à faire la preuve de son efficacité, les mécanismes d’actions de celle-ci demeurent encore aujourd’hui à l’état d’hypothèse. L’objectif de notre travail de thèse fut d’explorer le mécanisme d’action de la thérapie EMDR à travers différents paradigmes en EEG, TEP-scanner et IRMf, en comparant l’activité cérébrale avant et après traitement ou pendant les stimulations bilatérales alternées. Nous avons pu démontrer que la thérapie EMDR modifiait l’activité cérébrale d’un réseau cérébral impliqué dans le traitement émotionnel et la mémoire et d’une structure en particulier, le précuneus. Les stimulations bilatérales alternées qui sous-tendent l’action de l’EMDR activent elles aussi une partie de ce réseau expliquant l’impact de l’EMDR sur la mémoire traumatique. Pour la première fois, nous avons également montré que l’activité du précuneus avant traitement est capable de prédire l’intensité de la diminution des symptômes de TSPT. La durée du sommeil paradoxal avant traitement permet quant à elle de prédire le nombre de séances nécessaires pour obtenir la rémission. / Post-Traumatic Stress Disorder (PTSD) is a common condition affecting nearly 8% of the general population. This psychiatric pathology is expressed by a symptomatic square including a syndrome of repetition, avoidance, neurovegetative hyperactivation and a negative alteration of cognitions and mood. One of the most effective treatments in this pathology is a psychotherapy called EMDR for Eye Movement Desensitization and Reprocessing. Although this therapy no longer needs to prove its effectiveness, its mechanisms of action are still at the hypothesis stage today. The objective of our thesis work was to explore the mechanism of action of EMDR therapy through different paradigms in EEG, PET-scanner and fMRI, comparing brain activity before and after treatment or during bilateral alternating stimuli. We were able to demonstrate that EMDR therapy altered the brain activity of a brain network involved in emotional treatment and memory and of a particular structure, the precuneus. The alternating bilateral stimuli underlying the action of EMDR also activate part of this network explaining the impact of EMDR on traumatic memory. For the first time, we also have shown that the activity of the precuneus before treatment is able to predict the magnitude of the decrease in PTSD symptoms. The length of REM sleep before treatment can predict the number of sessions needed to reach remission.

A presente proposta visa examinar a formação histórica do conceito de célula visual. Pretendemos delimitar o estudo ao caso das células fotorreceptoras (cones e bastonetes). Em meados da década de 1860 a teoria vigente sobre o processo perceptivo era a das energias específicas dos nervos proposta por Johannes Müller (1801-1858) e desenvolvida posteriormente por Hermann Von Helmholtz (1821-1894). Examinaremos em nossa pesquisa a formação do conceito de tipos específicos de células nervosas associadas aos processos perceptivos (o foco do trabalho são as células do sistema visual). Esse debate envolve a formação dos conceitos de córtex visual, sistema visual, informação nervosa e célula nervosa. O período examinado será o entorno das duas últimas décadas do século XIX (décadas de 1880 e 1890), período em que Ferruccio Tartuferi (1852-1925) propõe a constituição híbrida da retina em 1887 e é marcada também pela formulação da teoria neuronal (teoria formulada principalmente pelo espanhol Santiago Ramón y Cajal) / The objective of the present study is to examine the historical formation of the visual cell concept, focussing on the the study of photoreceptor cells (cones and rods). In the mid-1860s, the current theory about the perceptual process was that of the specific energies of nerves proposed by Johannes Müller (1801-1858) and later developed by Hermann Von Helmholtz (1821-1894). Our research will examine the formation of the concept of specific types of nerve cells associated with perceptual processes (the focus of the work are the cells of the visual system). This debate involves the formation of the concepts of visual cortex, visual system, nervous information and nerve cell. The period examined will be the last two decades of the nineteenth century (1880s and 1890s), a period in which Ferruccio Tartuferi (1852-1925) proposed the hybrid constitution of the retina in 1887 and also marked by the formulation of neuronal theory mainly by the Spaniard Santiago Ramón y Cajal

A presente proposta visa examinar a formação histórica do conceito de célula visual. Pretendemos delimitar o estudo ao caso das células fotorreceptoras (cones e bastonetes). Em meados da década de 1860 a teoria vigente sobre o processo perceptivo era a das energias específicas dos nervos proposta por Johannes Müller (1801-1858) e desenvolvida posteriormente por Hermann Von Helmholtz (1821-1894). Examinaremos em nossa pesquisa a formação do conceito de tipos específicos de células nervosas associadas aos processos perceptivos (o foco do trabalho são as células do sistema visual). Esse debate envolve a formação dos conceitos de córtex visual, sistema visual, informação nervosa e célula nervosa. O período examinado será o entorno das duas últimas décadas do século XIX (décadas de 1880 e 1890), período em que Ferruccio Tartuferi (1852-1925) propõe a constituição híbrida da retina em 1887 e é marcada também pela formulação da teoria neuronal (teoria formulada principalmente pelo espanhol Santiago Ramón y Cajal) / The objective of the present study is to examine the historical formation of the visual cell concept, focussing on the the study of photoreceptor cells (cones and rods). In the mid-1860s, the current theory about the perceptual process was that of the specific energies of nerves proposed by Johannes Müller (1801-1858) and later developed by Hermann Von Helmholtz (1821-1894). Our research will examine the formation of the concept of specific types of nerve cells associated with perceptual processes (the focus of the work are the cells of the visual system). This debate involves the formation of the concepts of visual cortex, visual system, nervous information and nerve cell. The period examined will be the last two decades of the nineteenth century (1880s and 1890s), a period in which Ferruccio Tartuferi (1852-1925) proposed the hybrid constitution of the retina in 1887 and also marked by the formulation of neuronal theory mainly by the Spaniard Santiago Ramón y Cajal