Natural protected areas as biodiversity protection policies: perceptive characterization of sociocultural groups from the surrounding of the EPA of Catolé and Fernão Velho, State of Alagoas, Brazil - Nowadays, the world is passing through out a great increasing of devastation in natural environments, which have been drastically changed by different cultures. The discussion focusing the few protected areas which retain the biodiversity leads to reflections about what have been done in order to preserve the natural resources still remaining in the planet. In this direction, most of the nations that are preoccupied on the level of environmental degradation are creating legal procedures in order to protect their natural ecosystems. The appropriation and the neglect behavior of the human being related to the indiscriminate use of the natural resources of the planet have been made on an egoistic form. There is no consideration on the property pertaining to all generations. So, alternatives arise focusing to protect the natural wealth of human kind. Amongst them, it must be emphasized the creation of natural protected areas (called in Brazil Unidades de Conservação UCs), included in two different categories: 1. integral protection and 2. sustainable use. One of them is the Área de Proteção Ambiental APA (Environmental Protected Areas - EPA), which is classified in the category of sustainable use. The EPA of Catolé and Fernão Velho was created on the State of Alagoas, in Brazil, by the Law number 5,347, in May 27, 1992. As well as the majority of the created UCs, this EPA is in risky situation due to many negative anthropic actions even on its interior as well as on its surroundings. Considering this situation was developed this study in order to do an environmental evaluation of several activities related to the soil use and occupation in the surrounding of the Catolé forest, mainly the risks to the biodiversity. The dissertation is structured on three chapters: the Chapter 1 include the theoretical background based on two points: (1) environmental conservation as policies to protect biodiversity and (2) the participative management as tool for the sustainable development; the Chapter 2 is about the importance to develop researches on UCs; in the Chapter 3 are presented and discussed the field research results, including types of environmental negative impacts and perceptive characterization by different socioeconomic groups that act in the EPA and on its near surroundings). Previously, in February 2005, interviews were carried out in order to evaluate the present conditions of the UC management in the State of Alagoas. ... In order to detect if the management attended the Laws and to identify the difficulties for this activities, the questions were applied to the managers of the federal and state UC, respectively, Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis (IBAMA) and the Instituto do Meio Ambiente (IMA) in order to record the environmental changes: (1) to detect if the management attended the Laws and (2) to identify the difficulties for their management. From July 2005 to July 2006, ten visits were done in order to record the environmental changes. Five social-cultural groups took part of this study: (1) researchers, (2) teachers and (3) students of the local school (Colégio Estadual Onélia Campelo), and (4) inhabitants of the EPA surrounding area. Questionnaires with different contents were applied. For teachers, the main topics were: a) the level of knowledge about the forest near the school; b) inclusion or forest features as didactic contents; c) description of the landscape, fauna and flora. For students, were proposed some activities: a) drawings about the forest, its animals and plants; b) personal opinions about the importance of preserving the forest. The questions for the inhabitants focused: a) the animals sawn in the forest; b) the type of feelings about them; c) their position about preserving the forest. The 24 UC legally constituted in the State of Alagoas do not have a management plan. The special retraction of the studied forest remains in the last decade (reduced to 36%) reflects the accelerated deforestation due to irregular human occupation in the forest surrounding area as well as inside the EPA. The perceptive characterization of the forest by the different socio-cultural groups shows two different points of view: (1) A preservationist one, from the researchers, which consider the EPA an ecologic sanctuary, and, though, needs to be protect; and other (2) the utilitarist one, from teachers, students and inhabitants. The draws reflects an urbanizated forest used as pomar, way to school and to go home, playing area and place for using drugs. This study shows that the EPA of Catolé and Fernão Velho is in an advanced degradation stage, as a result of pottencially comprometedoras activities that lead to risks to the biodiversity an, as a consequence, to the environmental quality of the EPA even in its interior as well as on forest surrounding area. These activities have as probable causes, lacking of a management plan, policies and, mainly, information and conscientization on natural protect areas importance for the society. / Atualmente o mundo vem vivenciando uma acelerada destruição dos ambientes naturais, os quais têm sido drasticamente modificados pelas diferentes culturas que têm habitado a terra. A discussão em torno das poucas áreas protegidas que resguardam a biodiversidade conduz a reflexões sobre o que tem sido feito para se preservar o que ainda resta no planeta. Nesse sentido, a maioria das nações preocupadas com o estado de degradação ambiental vem estabelecendo medidas legais para proteger os seus ecossistemas naturais. A apropriação e descaso do ser humano em relação ao uso indiscriminado dos recursos naturais do planeta têm sido efetuados de forma egoísta, sem considerar que se trata de um bem pertencente a todas as gerações. Contra isto deve ser enfatizado a criação de Unidades de Conservação (UC s) incluídas em duas diferentes categorias: 1- unidades de proteção integral, 2- unidades de uso sustentável.Uma delas é a Área de Proteção Ambiental APA, que é classificada na categoria de uso sustentável. A APA do Catolé e Fernão Velho, criada pela Lei Estadual nº. 5.347 de 27 de maio de 1992, a APA do Catolé e Fernão Velho é uma UC criada do Estado de Alagoas, sendo incluída na categoria de uso sustentável. Assim como a maioria das UCs criadas, essa APA se encontra em situação de risco decorrente de várias ações antrópicas negativas tanto no seu interior como no seu entorno. Considerando esta situação foi efetuado este estudo que teve como objetivo geral fazer uma avaliação ambiental das várias atividades relacionadas ao uso e a ocupação do solo do entorno imediato da Mata do Catolé levando em consideração os riscos à biodiversidade. A dissertação está estruturada em três capítulos: capítulo I, inclui a fundamentação teórica da pesquisa tomando-se por pressupostos (1) a conservação ambiental como política de proteção à biodiversidade e (2) a gestão participativa como instrumento do desenvolvimento sustentável; capítulo II, destaca-se a importância do desenvolvimento de pesquisas em Unidades de Conservação e no capítulo III, apresenta-se e discutem-se os resultados da pesquisa de campo que incluiu os tipos de impactos ambientais negativos e a caracterização perceptiva de cinco grupos sócio-culturais da APA e de seu entorno. Para avaliar o estado atual de funcionamento das UC´s em Alagoas foram realizadas, inicialmente (fevereiro/2005) entrevistas com os responsáveis pela gestão de UC´s federais (IBAMA) e estaduais (IMA), com objetivos de diagnosticar se o funcionamento atendia à legislação e de identificar as dificuldades existentes em seus gerenciamentos. No período de julho de 2005 a julho de 2006 foram realizadas 10 visitas a fim de serem feitos os registros das alterações ambientais. ... Participaram da pesquisa cinco grupos sócio-culturais: (1) gestores (2) pesquisadores; (3) professores e (4) alunos do Colégio Estadual Onélia Campelo e (5) moradores do entorno. Tendo sido aplicados questionários com conteúdos diferentes. Para os gestores buscou-se dados para se fazer uma avaliação das UC s de Alagoas, para os professores, os tópicos relevantes foram: a) nível de conhecimento sobre a mata próxima à escola; b) inclusão da mata como conteúdo trabalhado em sala de aula; c) descrição da paisagem, fauna e flora. Solicitou-se aos alunos que: a) elaborassem desenhos sobre a mata, seus animais e plantas; b) emitissem opiniões sobre a importância de preservar a mata. Os tópicos apresentados aos moradores, enfocavam: a) os animais avistados na mata; b) o tipo de sentimento em relação aos mesmos; e c) a importância da preservação da mata, O questionário aplicado aos gestores enfocava As 24 UCs legalmente constituídas em Alagoas não apresentam plano de manejo. A retração espacial do remanescente de mata da APA estudada ocorrida na última década (36%) reflete o desmatamento acelerado pela ocupação humana irregular no entorno da mata e dentro da APA. A caracterização perceptiva da mata pelos diferentes grupos sócio-culturais revelou duas visões diferenciadas: (1) uma preservacionista, a dos pesquisadores, que a consideram um santuário ecológico, e, como tal, precisa de proteção; e (2) outra utilitarista, representada pelos professores, alunos e os moradores do entorno. Os desenhos dos alunos revelaram uma mata urbanizada usada como pomar, caminho para escola e casa, lazer e local para uso de drogas. Esse estudo revela que a APA do Catolé e Fernão Velho se encontra num estado avançado de degradação tendo sido observadas atividades potencialmente comprometedoras e com riscos à biodiversidade e à qualidade ambiental da APA tanto no seu interior quanto no entorno da mata. Essas atividades têm como possíveis causas, a falta de plano de manejo, de vontade política e de informação e conscientização da importância das Unidades de Conservação para a sociedade.

Desde a última década, o tema aprendizagem organizacional tem recebido atenção de profissionais e pesquisadores. No entanto, a aprendizagem que ocorre nas organizações vai além da de natureza pragmática, que entende a aprendizagem a partir de modelos normativos somente com o intuito de gerar mudanças. Em contraponto a essa linha, existe, na literatura, a busca pela compreensão da aprendizagem como um processo, seja ele técnico ou social. Dentre outras, convém o uso da teoria da estética organizacional para a concepção da aprendizagem que emerge a partir das interações sociais. Esta teoria caracteriza-se por contestar o pensamento positivista-funcionalista e vai obtendo mais espaço, à medida que vem sendo aprofundada e empregada por pesquisadores, a fim de compreenderem os fenômenos organizacionais. Meu objetivo nesse estudo foi identificar e analisar, à luz da teoria da estética organizacional, os processos de aprendizagem, a partir das práticas de trabalho de profissionais que atuam em uma revenda de móveis planejados. Para isso, além de identificar e descrever as práticas de trabalho das funções organizacionais dos sujeitos pesquisados, também foi preciso identificar e analisar as dimensões referentes aos artefatos e à linguagem da cultura organizacional da revenda, assim como identificar e compreender as percepções estéticas dos profissionais atuantes em campo. Para a viabilidade da pesquisa, desenvolvi um estudo etnográfico, realizado entre os meses de fevereiro de 2011 e janeiro de 2012, em uma revenda de móveis planejados, situada em Porto Alegre (RS). De modo complementar, esclareço algumas noções importantes do ramo da arquitetura, principalmente de interiores, e de aspectos do ato de ‘habitar’. Após fazer referência às faculdades perceptivas dos sujeitos pesquisados e como estas permitem a realização dos juízos estéticos, esclareço como a estética organizacional pode ser compreendida como um critério de decisão e conexão. A partir das dinâmicas de relacionamentos e da contínua construção de um ‘espírito do lugar’, discuto como esses aspectos consentem à arquitetura dos processos de aprendizagem na organização pesquisada, ressaltando a ‘reflexividade estética’. / Since last decade, the theme organizational learning has received attention from professionals and researchers. However, the learning that occurs in the organizations goes beyond the one of pragmatic nature, what understands learning from the normative models only with the intention of generating changes. Counterpointing to this line, there is in literature the search for the learning comprehension as a process, being it technical or social. Among others, it is advisable the use of the theory of organizational esthetics for the learning conception that emerges from the social interactions. This theory is characterized for questioning the positive-functionalist thought and is obtaining more space, as it is being deepen and used by researchers, aiming to understand the organizational phenomena. My objective in this study was to identify and analyze the learning processes from the working practices of professionals who act in a planned furniture store by the theory of organizational esthetics. For that, beyond identifying and describing the working practices from the organizational functions of the researched individuals, it was also necessary to identify and analyze the dimensions referring to the artifacts and to the language of the organizational culture of resale, as well as the identification and comprehension of the esthetics perceptions of the professionals who were acting in the area. To the research feasibility I developed an ethnographic study, performed between the months of February 2011 and January 2012 at a planned furniture store, located in Porto Alegre (RS). To complement, I clarify some important notions in the field of architecture, mainly of interiors, and about the aspects of the act of ‘inhabiting’. After making reference to the perceptive faculties of the researched individuals and how they allow the realization of esthetical commonsense, I explain how the organizational esthetics can be understood as a criterion of decision and connection. Beyond that, from the dynamics of relationship and the continuous construction of a ‘spirit of the place’, I discuss how these aspects agree to the architecture of learning processes in the organization researched, highlighting the ‘esthetic reflexivity’.

Objetivos: Verificar o efeito da veloplastia intravelar associada à palatoplastia secundária sobre a fala de pacientes com insuficiência velofaríngea (IVF), e comparar os resultados de fala entre os pacientes, de acordo com a extensão da falha no fechamento velofaríngeo aferida pela nasofaringoscopia. Modelo: Estudo prospectivo em pacientes com fissura palatina operada e IVF residual, avaliados 3 dias, em média, antes e 8 meses, em média, após a cirurgia, divididos em 2 grupos: um com falhas pequenas e outro com falhas de tamanho médio a grande no fechamento velofaríngeo. Diferenças entre grupos e etapas foram consideradas significantes ao nível de 5%. Local de Execução: Laboratório de Fisiologia, Hospital de Reabilitação de Anomalias Craniofaciais, Universidade de São Paulo (HRAC-USP). Participantes: 40 pacientes, de ambos os sexos, com idade entre 4 e 48 anos, sendo 25 com falhas pequenas (grupo I) e 15 com falhas médias ou grandes no fechamento velofaríngeo (grupo II). Variáveis: Hipernasalidade, emissão de ar nasal, distúrbios articulatórios compensatórios e função velofaríngea avaliados por meio de avaliação perceptiva da fala e nasalância obtida por meio da nasometria. Resultados: Após a cirurgia, verificou-se no grupo I, eliminação da hipernasalidade, emissão de ar nasal e distúrbio articulatório compensatório em 64%, 64% e 20% dos pacientes respectivamente. Em 44% dos casos deste grupo, a função velofaríngea passou a ser adequada e, também, em 44% houve normalização dos valores de nasalância. No grupo II verificou-se eliminação da hipernasalidade em 13%, da emissão de ar nasal em 20% e do distúrbio articulatório compensatório em 7%. Somente 7% dos pacientes deste grupo passaram a apresentar função velofaríngea adequada e em 14% houve normalização da nasalância após a cirurgia. Conclusões: A curto prazo, a veloplastia intravelar associada à palatoplastia secundária levou à melhora dos sintomas de fala da IVF na maioria dos pacientes estudados. Os resultados mostraram, ainda, que a cirurgia levou à melhora mais expressiva nos pacientes que apresentavam falhas no fechamento velofaríngeo de pequena extensão. / Objectives: To verify the effect of intravelar veloplasty associated with secondary palatoplasty on the speech of patients with velopharyngeal insufficiency (VPI) and to compare the speech outcomes among these patients, according to the extent of defect of velopharyngeal closure as analyzed by nasopharyngoscopy. Model: Prospective study of patients with repaired cleft palate and residual VPI, evaluated at 3 days before and 8 months after surgery in the average, who were divided into two groups: one with minor defect and the other with medium to large defect in velopharyngeal closure. Differences between groups and stages were considered significant at the 5% level. Setting: Laboratory Physiology of Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo (HRAC-USP). Participants: 40 patients of both genders, aged 4 to 48 years old, being 25 with minor defects (group I) and 15 with medium to large defects (group II) in velopharyngeal closure. Variables: Hypernasality, nasal air emission, compensatory articulation production and velopharyngeal function, evaluated by perceptive evaluation of speech and nasalance obtained by nasometry. Results: After surgery, group I exhibited elimination of hypernasality, nasal air emission and compensatory articulation production in 64%, 64% and 20% of patients, respectively. Adequate velopharyngeal function and normalization of nasalance values were observed in 44% of cases in this group. Group II presented elimination of hypernasality in 13%, nasal air emission in 20% and compensatory articulation production in 7%. Only 7% of patients in this group presented adequate velopharyngeal function and 14% exhibited normalization of nasalance after surgery. Conclusions: In the short term, intravelar veloplasty associated with secondary palatoplasty led to improvement in VPI-related speech symptoms in most patients. The results further demonstrated that surgery allowed greater improvement in patients presenting minor defects in velopharyngeal closure.

Desde a última década, o tema aprendizagem organizacional tem recebido atenção de profissionais e pesquisadores. No entanto, a aprendizagem que ocorre nas organizações vai além da de natureza pragmática, que entende a aprendizagem a partir de modelos normativos somente com o intuito de gerar mudanças. Em contraponto a essa linha, existe, na literatura, a busca pela compreensão da aprendizagem como um processo, seja ele técnico ou social. Dentre outras, convém o uso da teoria da estética organizacional para a concepção da aprendizagem que emerge a partir das interações sociais. Esta teoria caracteriza-se por contestar o pensamento positivista-funcionalista e vai obtendo mais espaço, à medida que vem sendo aprofundada e empregada por pesquisadores, a fim de compreenderem os fenômenos organizacionais. Meu objetivo nesse estudo foi identificar e analisar, à luz da teoria da estética organizacional, os processos de aprendizagem, a partir das práticas de trabalho de profissionais que atuam em uma revenda de móveis planejados. Para isso, além de identificar e descrever as práticas de trabalho das funções organizacionais dos sujeitos pesquisados, também foi preciso identificar e analisar as dimensões referentes aos artefatos e à linguagem da cultura organizacional da revenda, assim como identificar e compreender as percepções estéticas dos profissionais atuantes em campo. Para a viabilidade da pesquisa, desenvolvi um estudo etnográfico, realizado entre os meses de fevereiro de 2011 e janeiro de 2012, em uma revenda de móveis planejados, situada em Porto Alegre (RS). De modo complementar, esclareço algumas noções importantes do ramo da arquitetura, principalmente de interiores, e de aspectos do ato de ‘habitar’. Após fazer referência às faculdades perceptivas dos sujeitos pesquisados e como estas permitem a realização dos juízos estéticos, esclareço como a estética organizacional pode ser compreendida como um critério de decisão e conexão. A partir das dinâmicas de relacionamentos e da contínua construção de um ‘espírito do lugar’, discuto como esses aspectos consentem à arquitetura dos processos de aprendizagem na organização pesquisada, ressaltando a ‘reflexividade estética’. / Since last decade, the theme organizational learning has received attention from professionals and researchers. However, the learning that occurs in the organizations goes beyond the one of pragmatic nature, what understands learning from the normative models only with the intention of generating changes. Counterpointing to this line, there is in literature the search for the learning comprehension as a process, being it technical or social. Among others, it is advisable the use of the theory of organizational esthetics for the learning conception that emerges from the social interactions. This theory is characterized for questioning the positive-functionalist thought and is obtaining more space, as it is being deepen and used by researchers, aiming to understand the organizational phenomena. My objective in this study was to identify and analyze the learning processes from the working practices of professionals who act in a planned furniture store by the theory of organizational esthetics. For that, beyond identifying and describing the working practices from the organizational functions of the researched individuals, it was also necessary to identify and analyze the dimensions referring to the artifacts and to the language of the organizational culture of resale, as well as the identification and comprehension of the esthetics perceptions of the professionals who were acting in the area. To the research feasibility I developed an ethnographic study, performed between the months of February 2011 and January 2012 at a planned furniture store, located in Porto Alegre (RS). To complement, I clarify some important notions in the field of architecture, mainly of interiors, and about the aspects of the act of ‘inhabiting’. After making reference to the perceptive faculties of the researched individuals and how they allow the realization of esthetical commonsense, I explain how the organizational esthetics can be understood as a criterion of decision and connection. Beyond that, from the dynamics of relationship and the continuous construction of a ‘spirit of the place’, I discuss how these aspects agree to the architecture of learning processes in the organization researched, highlighting the ‘esthetic reflexivity’.

L'objectif général de cette thèse est de contribuer à l'exploration de la qualité sonore des salles de concert à partir d'une approche centrée sur l'identification de l'expérience sensible des mélomanes. Nous montrons d'abord les limites de l'approche traditionnelle de l'évaluation perceptive, principalement centrée sur des attributs reliés à la salle ou à la musique, et définis a priori à partir des connaissances des expérimentateurs, le plus souvent acousticiens, dans les termes de leur domaine scientifique ou avec des mots dont ils pensent partager avec les sujets les mêmes significations. Puis, reprenant les trois méthodes d'exploration de l'expérience subjective -enquêtes "hors situation d'écoute" (basées sur la mémoire), questionnaires dans les salles lors de concerts, et tests d'écoute en laboratoire-, nous les avons implémentées, mais dans un cadre théorique et méthodologique explicitement positionné en psychologie et en linguistique sur l'étude du sensible comme objet psychologique autonome. De plus, pour notre approche expérimentale en laboratoire, nous avons implémenté un système de décodage paramétrique basé sur le système SIRR (spatial impulse response rendering), permettant la reproduction de champs sonores à partir de réponses impulsionnelles des salles mesurées au format Ambisonics de premier ordre. La contribution de ce travail consiste à repérer les facteurs psychologiques reliés à l'écoute d'un concert dans une salle à partir de l'objectivation de l'expérience subjective des mélomanes et de leur évaluation de la qualité acoustique de la salle, et à partir de là, établir des relations avec les mesures acoustiques des salles étudiées. / The general purpose of this thesis is to explore the sound quality of concert halls by approaching it through the listeners’ sensory experience. We first show the limitations of the traditional approach to perceptual evaluation, principally centred on attributes related to hall or music, from the knowledge of experimenters, usually acousticians, and therefore pre-defined by their scientific field, or in common language they believe is shared by the subjects in terms of use and equivalence of meaning. Then, re-using the three methods for exploring subjective experience –extra-auditory enquiries “from memory”, questionnaire surveys within auditoria for given concerts, and laboratory listening tests–, we have implemented them, but within a theoretical and methodological framework, explicitly rooted in psychology and linguistics, and respecting sensibility as an autonomous psychological object of study. Furthermore, in our experimental laboratory approach, we have implemented a parametric decoding system based on SIRR (spatial impulse response rendering), and permitting the reproduction of sound fields from first-order Ambisonics room impulse responses. The contribution of this work thus consists in identifying the psychological factors related to concert listening in a hall by objectivising the subjective experience of listeners (music-lovers) and their evaluation of the acoustic qualities of an auditorium; and in establishing relationships between the psychological factors and the acoustic measurements in the studied auditoria.

Nous ne pouvons tout voir. L'attention, notre capacité à filtrer et moduler les informations, nous permet d'interagir de façon efficace avec le monde. Nous avons utilisé une technique non-invasive de modulation de l'activité cérébrale, la Stimulation Magnétique Transcrânienne (SMT) pour manipuler l'activité d'une région clé du réseau de l'attention spatiale, le champ oculomoteur frontal (FEF) droit. L'accent est mis sur les connexions anatomiques observées en IRM de diffusion sous-tendant la modulation de la perception visuelle. Après avoir présenté nos connaissances tirées de données comportementales, physiologiques et anatomiques ainsi que les techniques utilisées, nous présentons nos études qui montrent une amélioration des performances visuelles après des impulsions simples ou des trains d'impulsions de SMT à une fréquence spécifique (30Hz) appliqués sur le FEF droit juste avant l'apparition d'une cible visuelle. Nous examinons ensuite si des différences interindividuelles de connectivité anatomique influencent la modulation perceptive induite par SMT. Nous décrivons un faisceau fronto-tectal qui connecte le FEF avec le colliculus supérieurs et montrons que la probabilité de connexion entre ces deux régions dans l'hémisphère droit influence la contribution du FEF sur la détection visuelle. Nous décrivons aussi les trois branches du faisceau longitudinal supérieur et démontrons l'influence de la 1ère branche dans l'hémisphère droit sur la modulation visuelle induite par des trains de SMT à 30 Hz. Ces résultats suggèrent un rôle important de la connectivité anatomique dans la possibilité de synchroniser les aires d'un réseau à une fréquence spécifique. / We are unable to see everything. Attention, our ability to filter, select and modulate information, allows us to interact efficiently with the world. We employed a non-invasive brain stimulation technique, the Transcranial Magnetic Stimulation (TMS), to manipulate in humans the activity of a key area of the attentional network, the right Frontal Eye Field (FEF). Our work focuses on the characterization with diffusion MRI of anatomical connections and their role underlying the modulation of visual perception. We first introduce previous behavioral, physiological and anatomical findings and the techniques used in our work. We then present evidence showing an improvement of visual performances tied to activity patterns consisting in either single pulses or frequency-specific rhythmic TMS bursts (30Hz) applied over the right FEF, prior to the onset of a visual target. We also examine whether inter-individual differences in white matter connectivity could influence the modulatory role that the FEF exerts on visual perception. We describe a fronto-tectal pathway connecting the FEF with the superior colliculus and show that the probability of connection between these two sites in the right hemisphere influences the FEF contributions to visual detection. We also characterize the three branches of the superior longitudinal fasciculus connecting frontal and parietal lobes and demonstrate an influence of its first branch in the right hemisphere on visual modulation induced by frequency-specific TMS bursts. Our results suggest a crucial role in the modulation of visual perception of the anatomical connectivity to synchronize areas of a network at a specific frequency.

L'évaluation de la sonie globale d'un son non-stationnaire repose sur la transformation de nos sensations de sonie momentanées en une valeur scalaire unique reflétant notre impression globale a posteriori. Cette thèse approfondit la compréhension de ce processus dynamique dans le cas particulier de stimuli présentant des profils d'intensité croissants ou décroissants de quelques secondes. Partant de l'observation que les sons croissants sont perçus plus forts que les sons décroissants alors qu'ils contiennent la même énergie pendant la même durée, cette thèse aborde la question des origines de cette asymétrie perceptive sous différentes perspectives. Une approche systématique est adoptée afin d'évaluer les bases méthodologiques, contextuelles et physiques du phénomène. Il est montré que l'évaluation globale de la sonie d'un stimulus dynamique ne correspond pas une simple moyenne énergétique. Les jugements des auditeurs se fondent sur une intégration temporelle de la région la plus intense des stimuli, mais d'autres mécanismes sont impliqués; des asymétries dépendant de façon complexe et non-linéaire des caractéristiques du profil temporel et du niveau des stimuli sont observées. Les modèles de sonie actuels ne permettent pas directement d'expliquer ces résultats, ce qui soutient l'idée selon laquelle les mécanismes étudiés pourraient provenir de traitements auditifs ou décisionnels "haut-niveau" n'étant pas encore pris en considération dans ces modèles. De nouvelles perspectives de recherche pour l'étude du codage et du traitement de stimuli non-stationnaires par les systèmes sensoriels à partir d'asymétries perceptives avérées sont ainsi offertes. / Global loudness evaluation of a time-varying sound is based on the transformation of our momentary loudness sensations into a single scalar value that reflects our overall impression a posteriori. This thesis deepens the understanding of this dynamical process in the case of specific stimuli that rise or fall in level over a few seconds. Starting from the observation that rising tones are perceived louder than falling tones while both contain the same energy over the same duration, this thesis scrutinizes the origins of this perceptual asymmetry from various perspectives. A systematic approach is adopted to evaluate the methodological, contextual and physical bases of this phenomenon. It is demonstrated that global loudness evaluation of a dynamic stimulus does not correspond to a simple energetic mean. Listeners’ judgments rely on a temporal integration of the loudest region of the stimuli, but additional mechanisms are involved; asymmetries which depend on temporal profile characteristics and sound level in a complex and non-linear way are observed. Current loudness models cannot directly account for the effects highlighted throughout the different studies of this thesis, which supports the idea that the mechanism(s) under study might take place in high auditory or decisional stages not considered in these models. This research offers new perspectives to investigate the coding and the processing of time-varying stimuli by sensory systems from identified perceptual asymmetries.

La même entrée sensorielle ne provoque pas toujours la même réaction. Dans les expériences en laboratoire, un stimulus donné peut engendrer une réponse différente à chaque nouvel essai, en particulier à proximité du seuil sensoriel. Ce phénomène est généralement attribué à une source de bruit non spécifique qui affecte la représentation sensorielle du stimulus ou le processus décisionnel. Dans cette thèse, nous examinons l'hypothèse selon laquelle cette variabilité des réponses peut être attribuée en partie à des fluctuations mesurables et spontanées de l'état cérébral. Dans ce but, nous développons et évaluons deux ensembles d'outils. L’un est un ensemble de modèles et de méthodes psychophysiques permettant de suivre les variations de la performance perceptive avec une bonne résolution temporelle et avec précision, sur différentes échelles de temps. Ces méthodes s’appuient sur des procédures adaptatives initialement développées pour mesurer efficacement les seuils de perception statiques et sont étendues ici dans le but de suivre des seuils qui varient au cours du temps. Le deuxième ensemble d'outils que nous développons comprend des méthodes d'analyse de données pour extraire de signaux d’électroencéphalographie (EEG) une quantité prédictive de la performance comportementale à diverses échelles de temps. Nous avons appliqué ces outils à des enregistrements conjoints d’EEG et de données comportementales collectées pendant que des auditeurs normo-entendants réalisaient une tâche de discrimination de fréquence sur des stimuli auditifs proche du seuil de discrimination. Contrairement à ce qui a été rapporté dans la littérature concernant des stimuli visuels, nous n'avons pas trouvé de preuve d’un quelconque effet des oscillations EEG spontanées de basse fréquence sur la performance auditive. En revanche, nous avons trouvé qu'une part importante de la variabilité des jugements peut s’expliquer par des effets de l'historique récent des stimuli et des réponses sur la décision prise à un moment donné. / The same sensory input does not always trigger the same reaction. In laboratory experiments, a given stimulus may elicit a different response on each trial, particularly near the sensory threshold. This is usually attributed to an unspecific source of noise that affects the sensory representation of the stimulus or the decision process. In this thesis we explore the hypothesis that response variability can in part be attributed to measurable, spontaneous fluctuations of ongoing brain state. For this purpose, we develop and test two sets of tools. One is a set of models and psychophysical methods to follow variations of perceptual performance with good temporal resolution and accuracy on different time scales. These methods rely on the adaptive procedures that were developed for the efficient measurements of static sensory thresholds and are extended here for the purpose of tracking time-varying thresholds. The second set of tools we develop encompass data analysis methods to extract from electroencephalography (EEG) signals a quantity that is predictive of behavioral performance on various time scales. We applied these tools to joint recordings of EEG and behavioral data acquired while normal listeners performed a frequency-discrimination task on near-threshold auditory stimuli. Unlike what was reported in the literature for visual stimuli, we did not find evidence for any effects of ongoing low-frequency EEG oscillations on auditory performance. However, we found that a substantial part of judgment variability can be accounted for by effects of recent stimulus-response history on an ongoing decision.

Les technologies de relief tridimensionnel (3D) ont récemment reçu un nouvel attrait. Lesraisons potentielles sont que ces technologies peuvent fournir une expérience visuelle plusriche et plus immersive. En effet, un observateur peut extraire les disparités binoculairesprésentées entre les vues gauche et droite, pour retrouver plus efficacement la profondeur dela scène visuelle observée, et ainsi, trouver une nouvelle dimension dans le contenu.Cependant, tandis que la valeur de la profondeur est plutôt bien appréciée, un certain nombrede problèmes qui impactent la qualité de l’expérience dans les représentations 3D ont étéidentifiés. L’objective de cette thèse est d’étudier les principaux facteurs qui affectent laqualité de l’expérience en stéréoscopie dans le but de fournir des méthodes qui pourraientaméliorer l’utilisation des systèmes stéréoscopiques. Trois aspects majeurs de la qualité del’expérience sont adressés : (1) les sources et causes de la fatigue visuelle, (2) les distorsionsperceptives et (3) l’amélioration de la qualité de l’expérience en 3D au travers de l’adaptationdu contenu visuel. Pour étudier la fatigue visuelle, les mouvements de vergence étaientmesurés à la fois avec un écran 3D et avec un système à double écran qui permettaient laprésentation de stimuli avec les informations de disparité et de flou présentés en congruencecomme en incongruence. L’effet de la stéréoscopie sur les mouvements de vergence a étéétudié dans le but de tester si la mesure oculaire pouvait être utilisée comme indicateur defatigue visuelle. Le sujet suivant étudiait la consistance de la perception des formes 3Dstéréoscopiques en fonction de distances virtuelles induites par la disparité et par le signald’accommodation. Le rôle de la taille de la pupille et de la profondeur de champ enstéréoscopie étaient étudiés par la manipulation de la taille de la pupille avec deux conditionsd’illumination contrôlée. Finalement, l’amélioration de la perception de la forme 3D estquestionnée au travers de l’adaptation du contenu visuel en fonction de la mesure de seuilsperceptifs individuels pour des stimuli se déplaçant en profondeur. / Stereoscopic 3-Dimensional (S3D) technology has recently received growing attraction,potentially because it provides a more informative and more immersive visual experience.Indeed, the viewer may extract the binocular disparities displayed between the left and theright views, more efficiently retrieve the depth of the observed visual scene, and thus, givevisual content another dimension. However, while the additional value of depth is ratherappreciated, a number of problems have been raised that impact the Quality of Experience(QoE) in S3D representations. The objective of this thesis is to investigate the main factorsaffecting QoE in stereopsis in order to provide guidelines towards the improvement andfurther use of stereoscopic systems. Three main aspects of QoE in S3D are addressed: (1) thesources and causes of visual fatigue, (2) the perceptual distortions arising in S3D and, (3) theimprovement of S3D QoE through content adaptation. To study visual fatigue in S3D,vergence eye movements were measured both in S3D display and in dual-screen display thatenables the presentation of matched disparity and defocus stimuli. The effect of stereopsis onvergence movements was studied so as to test whether vergence tracking can be used asindicator of visual fatigue. The next topic investigated the consistency in stereoscopic 3Dshape perception as a function of vergence distance and accommodation distance. The role ofthe pupil size and the depth of focus in S3D were evaluated by manipulating the pupilaperture with two controlled lighting conditions. Finally, the improvement of 3D shapeperception is addressed through content adaptation according to individual perceptionthresholds measurement for motion-in-depth stimuli.

La capacité du système visuel humain à compléter une image partiellement dévoilée et à en dériver une forme globale à partir de ses fragments visibles incomplets est un phénomène qui suscite, jusqu’à nos jours, l’intérêt de nombreux scientifiques œuvrant dans différents milieux de recherche tels que l’informatique, l’ingénierie en intelligence artificielle, la perception et les neurosciences. Dans le cadre de la présente thèse, nous nous sommes intéressés spécifiquement sur les substrats neuronaux associés à ce phénomène de clôture perceptive. La thèse actuelle a donc pour objectif général d’explorer le décours spatio-temporel des corrélats neuronaux associés à la clôture perceptive au cours d’une tâche d’identification d’objets. Dans un premier temps, le premier article visera à caractériser la signature électrophysiologique liée à la clôture perceptive chez des personnes à développement typique dans le but de déterminer si les processus de clôture perceptive reflèteraient l’interaction itérative entre les mécanismes de bas et de haut-niveau et si ceux-ci seraient sollicités à une étape précoce ou tardive lors du traitement visuel de l’information. Dans un deuxième temps, le second article a pour objectif d’explorer le décours spatio-temporel des mécanismes neuronaux sous-tendant la clôture perceptive dans le but de déterminer si les processus de clôture perceptive des personnes présentant un trouble autistique se caractérisent par une signature idiosyncrasique des changements d’amplitude des potentiels évoqués (PÉs). En d’autres termes, nous cherchons à déterminer si la clôture perceptive en autisme est atypique et nécessiterait davantage la contribution des mécanismes de bas-niveau et/ou de haut-niveau. Les résultats du premier article indiquent que le phénomène de clôture perceptive est associé temporellement à l’occurrence de la composante de PÉs N80 et P160 tel que révélé par des différences significatives claires entre des objets et des versions méconnaissables brouillées. Nous proposons enfin que la clôture perceptive s’avère un processus de transition reflétant les interactions proactives entre les mécanismes neuronaux œuvrant à apparier l’input sensoriel fragmenté à une représentation d’objets en mémoire plausible. Les résultats du second article révèlent des effets précoces de fragmentation et d’identification obtenus au niveau de composantes de potentiels évoqués N80 et P160 et ce, en toute absence d’effets au niveau des composantes tardives pour les individus avec autisme de haut niveau et avec syndrome d’Asperger. Pour ces deux groupes du trouble du spectre autistique, les données électrophysiologiques suggèrent qu’il n’y aurait pas de pré-activation graduelle de l’activité des régions corticales, entre autres frontales, aux moments précédant et menant vers l’identification d’objets fragmentés. Pour les participants autistes et avec syndrome d’Asperger, les analyses statistiques démontrent d’ailleurs une plus importante activation au niveau des régions postérieures alors que les individus à développement typique démontrent une activation plus élevée au niveau antérieur. Ces résultats pourraient suggérer que les personnes du spectre autistique se fient davantage aux processus perceptifs de bas-niveau pour parvenir à compléter les images d’objets fragmentés. Ainsi, lorsque confrontés aux images d’objets partiellement visibles pouvant sembler ambiguës, les individus avec autisme pourraient démontrer plus de difficultés à générer de multiples prédictions au sujet de l’identité d’un objet qu’ils perçoivent. Les implications théoriques et cliniques, les limites et perspectives futures de ces résultats sont discutées. / The human visual system has come to prevail over partially hidden boundaries and edges of objects in order to render a unified and holistic representation of the surrounding world. This phenomenon, also referred to as perceptual closure, was further investigated in the context of this current thesis. More precisely, this doctoral thesis aimed at examining the neural mechanisms underlying perceptual closure processes. In order to achieve this goal, the first study to track the spatio-temporal dynamics of electrical brain activity during a pictorial object recognition task to determine whether closure processes are reflect an interplay between low-level and higher-level mechanisms and whether they are solicited during early or late stages of visual processing. We found that perceptual closure is temporally linked to the occurrence of the N80 and P160 which is the earliest negative ERP component sensitive to closure processes reported until now in previous similar studies. Results indicate that closure processes are implicated earlier during visual processing of fragmented object images. We propose here that perceptual closure is a transitional process that reflects the proactive interactions between neural mechanisms trying to match fragmented current sensory input with memory representations. Furthermore, the second study sought to explore the time-course of neural correlates underpinning perceptual closure, during an object recognition task, to determine whether closure processes are associated with an abrupt or gradual change in ERP responses in adults with high functioning autism (HFA), Asperger’s Syndrome (AS) and in typically developing (TD) individuals. We found that, in individuals with HFA and AS, perceptual closure was associated with changes in early ERP (N80 and P160) responses for fragmentation and identification effects, while there were no significant modulations of later ERP responses. However, for TD individuals, perceptual closure was characterized by significant differences in early ERP responses (N80 and P160) between objects and non-objects as well as gradual modulations in late ERP responses for identification effects (450-550ms). Our results suggest that adults with autism rely mostly on low-level processes to achieve closure and do not illustrate the characteristic interplay between early and late ERP responses observed in typically developed individuals, thus revealing the atypicality of perceptual closure mechanisms in this population. We propose here that the interactive matching of incoming fragmented visual information with corresponding candidate object representations is atypical in individuals with autism. Following these articles, we will discuss the theoretical and clinical implications of this work. Finally, we will also propose limitations within our studies and discuss new perspectives for future research.