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INTRODUÇÃO: Evidências relevantes acerca dos benefícios da hipotermia terapêutica provieram da utilização de técnicas de resfriamento sistêmico. Essas técnicas, no entanto, podem causar complicações graves que poderiam ser evitadas com métodos de hipotermia encefálica seletiva. O presente estudo objetiva: 1) verificar a viabilidade da hipotermia encefálica exclusiva através de um sistema de resfriamento nasofaríngeo concomitante ao de preservação da temperatura corpórea em suínos e 2) investigar os efeitos da hipotermia encefálica exclusiva nas variáveis fisiológicas sistêmicas e encefálicas. MÉTODOS: Dez suínos híbridos foram submetidos a resfriamento nasofaríngeo durante 60 minutos e subsequente reaquecimento espontâneo. Foram obtidos dados referentes a: pressão arterial média, débito cardíaco, temperatura encefálica, pressão parcial de oxigênio do tecido encefálico (PbtO2, do inglês, pressure of brain tissue O2), velocidade do fluxo sanguíneo nas artérias encefálicas, índice de resistência e índice de pulsatilidade. RESULTADOS: O resfriamento nasofaríngeo associou-se à um decréscimo gradual da temperatura encefálica, que foi mais marcante no hemisfério cerebral esquerdo (p < 0,01). Neste hemisfério, houve redução de 1,47 ± 0,86°C nos primeiros 5 minutos (p < 0,01), 2,45 ± 1,03°C aos 10 minutos e 4,45 ± 1,36°C após 1 hora (p < 0,01). A diferença entre as temperaturas cerebral sistêmica foi 4,57 ± 0,87°C (p < 0,01). As temperaturas centrais (retal, esofágica e da artéria pulmonar), assim como a hemodinâmica encefálica e sistêmica, mantiveram-se estáveis durante o procedimento. Houve diminuição significativa da PbtO2, concomitantemente ao decréscimo da temperatura encefálica. CONCLUSÕES: A indução de hipotermia encefálica exclusiva é possível através de resfriamento nasofaríngeo associado a medidas de preservação da temperatura sistêmica. O resfriamento encefálico exclusivo não influencia as funções hemodinâmicas sistêmicas e encefálicas, contudo reduz significativamente a PbtO2 / INTRODUCTION: Relevant evidences for the use of therapeutic hypothermia derive from studies using whole body cooling methods. These methods can lead to serious complications. To avoid such complications, selective brain cooling methods were developed. The objective of this study was: 1) to verify the feasibility of exclusive brain hypothermia by means of nasopharyngeal cooling along with measures of systemic temperature preservation in an experimental swine model, and 2) to investigate the influence of the exclusive brain cooling on cerebral and systemic hemodynamics as well as on cerebral oxygenation. METHODS: Ten hybrid swine underwent nasopharyngeal cooling for 60 minutes, followed by spontaneous rewarming. A number of physiological variables were monitored: arterial blood pressure, cardiac output, temperature in the right and left cerebral hemispheres, pressure of brain tissue O2, cerebral blood flow velocities, resistance index, and pulsatility index. RESULTS: Nasopharyngeal cooling was associated with decrease in brain temperature, which was more significant in the left cerebral hemisphere (p < 0,01). There was a reduction of 1.47 ± 0.86°C in the first 5 minutes (p < 0.01), 2.45 ± 1.03°C within 10 min, and 4.45 ± 1.36°C after 1 hour (p < 0.01). The brain-core gradient was 4.57 ± 0.87°C (p < 0,001). Rectal, esophageal, and pulmonary artery temperatures, as well as brain and systemic hemodynamics, remained stable during the procedure. PbtO2 values significantly decreased following the brain cooling. CONCLUSION: Achievement of exclusive brain hypothermia is feasible by means of nasopharyngeal cooling associated with measures of systemic temperature preservation. Selective brain cooling does not influence both systemic and cerebral hemodynamics, except PbtO2, which decreased significantly

Les jeux vidéo à interface gestuelle permettent des interactions intéressantes entre le joueur et le jeu. Pour évaluer ce nouveau type de jeux vidéo, la méthode d'évaluation subjective courante serait insuffisante (Mandryk, R. L., Inkpen, K. M., et Calvert, T. W., 2006). Notre recherche essaie d'associer l'évaluation objective à l'évaluation subjective pour mesurer la qualité d'immersion des jeux vidéo conçus pour la Kinect — un accessoire de la console Xbox de Microsoft, permettant de jouer sans la manette. Notre corpus comporte 18 sujets (joueurs intensifs et occasionnels) et 3 jeux Kinect (Body and Brain Connection, Child of Eden et Joy Ride). Notre objectif est de développer une méthode d’évaluation la qualité d'immersion du jeu vidéo à l’interface gestuelle. Nous nous sommes basé d’une part sur un questionnaire conçu à partir des critères d’évaluation du Flux dans le jeu vidéo de Sweetser et Wyeth (2005) et des principes d’utilisabilité (Nielsen, 1994a, b; Bastien et Scapin, 1993; Johnson et Wiles, 2003), avec un questionnaire adapté par les chercheurs du DESS Design de jeu de l’Université de Montréal. Et d'autre part, nous nous avons intégré la mesure des réactions physiologiques des joueurs (la réponse galvanique de la peau, le pouls du volume sanguin, la respiration), les réactions oculaires (le diamètre des pupilles, le temps de fixation) et les expressions faciales (la joie, la tristesse, la colère, la peur, la surprise et le dégoût) du joueur. Nous nous sommes appuyé sur des postulats théoriques provenant du domaine de l'interaction humain-ordinateur et du design des jeux vidéo. Nous avons étudié en particulier les réactions physiologiques, oculaires, les expressions faciales et nous avons cherché à faire le lien avec les notions de présence et d'immersion dans le domaine des jeux vidéo. L’analyse des résultats a montré des corrélations entre les réactions physiologiques, oculaires et les réponses subjectives des participants aux questionnaires. Par exemple on observe une corrélation négative entre la pression sanguine (BVP) et la concentration du joueur, une corrélation positive entre la respiration et le diamètre des pupilles et le sentiment d'immersion du joueur, etc. Ces résultats permettraient de confirmer la faisabilité de notre méthode d’évaluation. i Ensuite, nous avons comparé les trois jeux en fonction des composantes de l’immersion afin de trouver le jeu le plus immersif. Le résultat a montré que le jeu Body and Brain Connection était le plus prisé par les participants et que le niveau de défi bien calibré et la facilité de contrôle étaient les deux facteurs principaux de la réussite du jeu Body and Brain. Nous avons également comparé les joueurs intensifs et les joueurs occasionnels en fonction des composantes de l’immersion pour voir la différence de point de vue des joueurs sur la Kinect. Le résultat a montré qu’il n’y avait pas de différence entre les deux types de joueurs. / The gesture-based video games offers interesting new ways of interacting between the player and the game. In order to evaluate this new type of games, current subjective methods of evaluating games isn't sufficiently robust. Our research tries to combine the objective and subjective methods for measuring the qualities of immersion of video games played with Kinect - an accessory for Xbox console from Microsoft, to play without the controller. Our corpus consists of 18 subjects (intensive and casual players) and 3 Kinect games. Our goal is to develop a method for assessing the quality of gesture-based video games. We relied in part on a questionnaire developed from the criteria for player enjoyment in games (Sweetser and Wyeth, 2005) and the usability questionnaire (Nielsen, 1994a, b; Bastien et Scapin, 1993; Johnson et Wiles, 2003), designed by the researchers of DESS Design de jeux, University of Montreal. And secondly, we integrated the measures of physiological responses (the galvanic skin response, the blood volume pulse, the respiration), the ocular reactions (the pupil’s diameter, fixation time) and facial expressions (joy, sadness, anger, fear, surprise and disgust) of the player. We relied on theoretical assumptions from the field of human-computer interaction and games design. We studied in particular physiological responses, eye movements, facial expressions and the notions of presence and immersion in video games. The analysis shows correlations between the physiological reactions, the eye movements and the player's subjective responses. For example, we observed negative correlation between blood volume pulse (BVP) and the concentration of the player, positive correlations between respiration and pupil diameter and the sense of immersion the player, etc. These results would confirm the feasibility of our evaluation method. Then, we compared these three games in terms of five components of immersion to find the most immersive game. The result showed that the game Body and Brain Connection was most appreciated by the participants and that the level of challenge properly calibrated and the ease of control were the two main factors of success of the game Body and Brain. iii We also compared intensive gamers and casual players according to the components of immersion to see the difference between their attitudes toward the Kinect. The result showed that there was no difference between the two types of players. / Les données sont analysées par le logiciel conçu par François Courtemanche et Féthi Guerdelli. L'expérimentation des jeux a eu lieu au Laboratoire de recherche en communication multimédia de l'Université de Montréal.

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INTRODUÇÃO: Evidências relevantes acerca dos benefícios da hipotermia terapêutica provieram da utilização de técnicas de resfriamento sistêmico. Essas técnicas, no entanto, podem causar complicações graves que poderiam ser evitadas com métodos de hipotermia encefálica seletiva. O presente estudo objetiva: 1) verificar a viabilidade da hipotermia encefálica exclusiva através de um sistema de resfriamento nasofaríngeo concomitante ao de preservação da temperatura corpórea em suínos e 2) investigar os efeitos da hipotermia encefálica exclusiva nas variáveis fisiológicas sistêmicas e encefálicas. MÉTODOS: Dez suínos híbridos foram submetidos a resfriamento nasofaríngeo durante 60 minutos e subsequente reaquecimento espontâneo. Foram obtidos dados referentes a: pressão arterial média, débito cardíaco, temperatura encefálica, pressão parcial de oxigênio do tecido encefálico (PbtO2, do inglês, pressure of brain tissue O2), velocidade do fluxo sanguíneo nas artérias encefálicas, índice de resistência e índice de pulsatilidade. RESULTADOS: O resfriamento nasofaríngeo associou-se à um decréscimo gradual da temperatura encefálica, que foi mais marcante no hemisfério cerebral esquerdo (p < 0,01). Neste hemisfério, houve redução de 1,47 ± 0,86°C nos primeiros 5 minutos (p < 0,01), 2,45 ± 1,03°C aos 10 minutos e 4,45 ± 1,36°C após 1 hora (p < 0,01). A diferença entre as temperaturas cerebral sistêmica foi 4,57 ± 0,87°C (p < 0,01). As temperaturas centrais (retal, esofágica e da artéria pulmonar), assim como a hemodinâmica encefálica e sistêmica, mantiveram-se estáveis durante o procedimento. Houve diminuição significativa da PbtO2, concomitantemente ao decréscimo da temperatura encefálica. CONCLUSÕES: A indução de hipotermia encefálica exclusiva é possível através de resfriamento nasofaríngeo associado a medidas de preservação da temperatura sistêmica. O resfriamento encefálico exclusivo não influencia as funções hemodinâmicas sistêmicas e encefálicas, contudo reduz significativamente a PbtO2 / INTRODUCTION: Relevant evidences for the use of therapeutic hypothermia derive from studies using whole body cooling methods. These methods can lead to serious complications. To avoid such complications, selective brain cooling methods were developed. The objective of this study was: 1) to verify the feasibility of exclusive brain hypothermia by means of nasopharyngeal cooling along with measures of systemic temperature preservation in an experimental swine model, and 2) to investigate the influence of the exclusive brain cooling on cerebral and systemic hemodynamics as well as on cerebral oxygenation. METHODS: Ten hybrid swine underwent nasopharyngeal cooling for 60 minutes, followed by spontaneous rewarming. A number of physiological variables were monitored: arterial blood pressure, cardiac output, temperature in the right and left cerebral hemispheres, pressure of brain tissue O2, cerebral blood flow velocities, resistance index, and pulsatility index. RESULTS: Nasopharyngeal cooling was associated with decrease in brain temperature, which was more significant in the left cerebral hemisphere (p < 0,01). There was a reduction of 1.47 ± 0.86°C in the first 5 minutes (p < 0.01), 2.45 ± 1.03°C within 10 min, and 4.45 ± 1.36°C after 1 hour (p < 0.01). The brain-core gradient was 4.57 ± 0.87°C (p < 0,001). Rectal, esophageal, and pulmonary artery temperatures, as well as brain and systemic hemodynamics, remained stable during the procedure. PbtO2 values significantly decreased following the brain cooling. CONCLUSION: Achievement of exclusive brain hypothermia is feasible by means of nasopharyngeal cooling associated with measures of systemic temperature preservation. Selective brain cooling does not influence both systemic and cerebral hemodynamics, except PbtO2, which decreased significantly