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1

Deplancke, Antoine. "Approche psychophysique des dissociations perception-action : effet de la détection de distracteurs au seuil sur l’atteinte de cibles visuelles." Thesis, Lille 3, 2012. http://www.theses.fr/2012LIL30033/document.

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Анотація:
La théorie dominante suggérant une séparation entre une vision consciente pour la perception et une vision non consciente pour l'action au sein du système visuel fut particulièrement discutée au cours des dernières décennies. La thèse défendue ici se positionne dans le cadre d'une approche alternative reposant sur une évaluation conjointe des réponses motrice et perceptive en présence de stimuli au seuil perceptif. Les travaux réalisés dans ce contexte ont initialement porté sur les temps de réaction et ont contribué au développement d'un modèle psychophysique postulant que les réponses perceptives et motrices dépendraient d'un signal sensoriel unique mais de seuils de décision spécifiques. Les trois études réalisées au cours de cette thèse ont permis de tester ces propositions à partir de travaux portant sur le contrôle moteur manuel. Tout en confirmant une forte association entre les traitements visuels pour la perception et pour l'action, ces travaux ont permis de mettre en évidence un rôle important des conditions expérimentales (par exemple le contraste des stimuli et la présence ou non d'un masque visuel) dans les résultats obtenus. Les résultats se sont révélés compatibles avec les modèles neurophysiologiques du masquage visuel qui postulent que la réponse neurale à une stimulation visuelle est constituée d'une vague d'activation feedforward associée à la présence physique de la stimulation et de boucles de rétroaction liées à la perception consciente de celle-ci. Nos travaux ont également permis d'adapter au contrôle moteur manuel le modèle de décision à signal unique initialement développé dans le cadre des études portant sur les temps de réaction
The dominant position of a separation between a conscious vision for perception and an unconscious vision for action within the visual system has been particularly discussed in the last decades. The present dissertation is to be placed in the context of an alternative approach consisting in evaluating jointly both perceptual and motor responses in the presence of near-treshold visual stimuli. Previous work within this framework, which have mainly concerned reaction times, have contributed to develop a psychophysical model in which perceptual and motor decision are taken relatively to the same single incoming signal but are based on different tresholds. The three studies conducting during this PhD aimed to testing these proposals in experiments involving manual motor control. While confirming the strong link between perceptual and motor processing within the visual system, the results obtained in these studies underlined the importance of experimental parameters such as the contrast of the stimuli and the presence of visual masks. These results are congruent with neurophysiological models of visual masking, which postulate that the neural response to a visual stimulus is composed of a transient feedforward sweep of activation related to the presence of as stimulus and recurrent feedback loops linked to the conscious perception of this stimulus. Our work also led to the adaptation to manual motor control of the single signal decisional model initially developed on the basis of reaction time studies
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2

Delabarre, Bertrand. "Contributions to dense visual tracking and visual servoing using robust similarity criteria." Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1S124/document.

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Анотація:
Dans cette thèse, nous traitons les problèmes de suivi visuel et d'asservissement visuel, qui sont des thèmes essentiels dans le domaine de la vision par ordinateur. La plupart des techniques de suivi et d'asservissement visuel présentes dans la littérature se basent sur des primitives géométriques extraites dans les images pour estimer le mouvement présent dans la séquence. Un problème inhérent à ce type de méthode est le fait de devoir extraire et mettre en correspondance des primitives à chaque nouvelle image avant de pouvoir estimer un déplacement. Afin d'éviter cette couche algorithmique et de considérer plus d'information visuelle, de récentes approches ont proposé d'utiliser directement la totalité des informations fournies par l'image. Ces algorithmes, alors qualifiés de directs, se basent pour la plupart sur l'observation des intensités lumineuses de chaque pixel de l'image. Mais ceci a pour effet de limiter le domaine d'utilisation de ces approches, car ce critère de comparaison est très sensibles aux perturbations de la scène (telles que les variations de luminosité ou les occultations). Pour régler ces problèmes nous proposons de nous baser sur des travaux récents qui ont montré que des mesures de similarité comme la somme des variances conditionnelles ou l'information mutuelle permettaient d'accroître la robustesse des approches directes dans des conditions perturbées. Nous proposons alors plusieurs algorithmes de suivi et d'asservissement visuels directs qui utilisent ces fonctions de similarité afin d'estimer le mouvement présents dans des séquences d'images et de contrôler un robot grâce aux informations fournies par une caméra. Ces différentes méthodes sont alors validées et analysées dans différentes conditions qui viennent démontrer leur efficacité
In this document, we address the visual tracking and visual servoing problems. They are crucial thematics in the domain of computer and robot vision. Most of these techniques use geometrical primitives extracted from the images in order to estimate a motion from an image sequences. But using geometrical features means having to extract and match them at each new image before performing the tracking or servoing process. In order to get rid of this algorithmic step, recent approaches have proposed to use directly the information provided by the whole image instead of extracting geometrical primitives. Most of these algorithms, referred to as direct techniques, are based on the luminance values of every pixel in the image. But this strategy limits their use, since the criteria is very sensitive to scene perturbations such as luminosity shifts or occlusions. To overcome this problem, we propose in this document to use robust similarity measures, the sum of conditional variance and the mutual information, in order to perform robust direct visual tracking and visual servoing processes. Several algorithms are then proposed that are based on these criteria in order to be robust to scene perturbations. These different methods are tested and analyzed in several setups where perturbations occur which allows to demonstrate their efficiency
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3

de, Cabo Portugal Sebastian. "Non Visuals : Material exploration of non-visual interaction design." Thesis, Umeå universitet, Designhögskolan vid Umeå universitet, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-182466.

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Анотація:
Design is all about visuals, or that is what I have found out during this thesis, from the process materials to the outcome our main entry point to any problem is how will we solve it visually so it’s understandable for the general user. This aspect is problematic in itself due to the fact that we, as humans, understand the world and the things around using all our senses continuously, even though we can forget as visuals are so overpowering. There is a huge opportunity area in exploring our other senses and bringing them back to technology, and this can be seen in works in the past like Tangible Interactions [1] or Natural User Interfaces [2]. But in this moment in time, where all these new technologies like VR/AR and IoT are about to enter our lives and change them forever, this topic is more important than ever. We have already seen what happens when we turn humans into mere machines with some fingers as interactive inputs, and barely any senses to process all the information given to us. Now that these technologies are still young and malleable, we can direct the future to where we want it instead of being guided by the technology itself. To do this we need to reimagine the design process, not reinvent the wheel, but add experts which we currently leave behind and I argue are key to unlock these technologies, experts not only of the technological side of things but on the human side too, like physiotherapists and dancers. Add also people who we never think about when we think of VR like visually impaired users, which could make these technologies inclusive since early on, instead of as an afterthought like we usually do. Not only people, but we also need to add new materials to understand how we use our senses and explore ways that we can understand and explore them differently; like bodystorming and improv theatre because when things aren’t visual, how do you sketch it? A sketch turns into a video about movement. The end result provides a wide breadth of examples of the types of innovations that can come out of using these new design materials, and to open new frontiers. From a VR game with no visuals whatsoever to an AR location based story game, to a home sized multimodal operating system containing several different apps controlled through physical movement. The examples open up the space instead of closing into a single solution. This is just the tip of the iceberg, a hope that others will be inspired by it and continue with this journey that has just started, to guide the future into one that is more technological and at the same time more human than ever before. What we know is that VR does not equate Visual Reality.
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4

Camargo, Marina von Zuben de Arruda. "Propriedades espaço-temporais da acuidade vernier no córtex visual humano usando potenciais visuais provocados de varredura." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/47/47135/tde-12062012-160008/.

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Анотація:
Esta pesquisa pretendia estabelecer um mapa espaço temporal das respostas de vernier no córtex visual humano. O uso do potencial visual provocado de varredura (PVPv) proporciona medidas eficientes e sensíveis dos limiares de vernier com os quais se pode começar a examinar as respostas corticais de vernier no âmbito dos parâmetros espaço temporais. As respostas de vernier foram avaliadas em relação à hipótese de que os sinais retinianos provenientes das células ganglionares da via magnocelular e não da via parvocelular compõem o input neural para córtex que é utilizado para gerar as respostas de vernier (tarefas de localização de alta precisão Lee et a., 1990; Lee et al., 1995). Métodos: As respostas de vernier no córtex humano foram medidas por meio do potencial visual provocado de varredura (PVPv). Quebras de vernier foram introduzidas em grades de ondas quadradas de produzindo colunas verticais intercaladas de barras estáticas e móveis. Medidas binoculares da acuidade vernier foram feitas em grades de alto contraste (64%) em função de 3 frequências temporais (3, 6 e 15 Hz) e 2 frequências espaciais (1 e 8 c/g). Medidas utilizando grades de baixo contraste foram feitas em função de 3 frequências temporais (3, 6 e 10Hz) e 3 frequências espaciais (1, 2 e 8c/g) em ambos os protocolos (alto e baixo contraste) as medidas foram feitas utilizando o PVPv. Foi utilizado o sistema POWER DIVA que utiliza a metodologia dos mínimos quadrados recursivos para extrair a amplitude e fase da resposta nos harmônicos selecionados da frequência do estímulo. Foram analisados o primeiro (1F1) e o segundo (2F1) harmônicos neste estudo. Com base em estudos anteriores, assume-se que o primeiro componente harmônico refere-se às respostas ao estímulo de vernier, e o segundo às respostas ao movimento relativo dos elementos do estímulo. Esta hipótese foi testada por meio da utilização de protocolos controle para ambos os arranjos de estímulos (alto e baixo contraste) em que foram utilizados os mesmos parâmetros, porém com deslocamentos entre as barras completamente simétricos (elementos da grade jamais se alinhavam). O sistema POWER DIVA calcula para cada segundo de janela de análise (bin) a amplitude local. A amplitude média do ruído nos 10 bins de análise é utilizada para calcular a razão sinal ruído para cada bin. Apenas sinais com razão sinal ruído maior que 3 foram considerados resposta. A média vetorial de 8 tentativas para cada condição de estímulo foi utilizada para determinar os limiares.Resultados: Os dados são consistentes com dados psicofísicos anteriores, especialmente os dados de Bradley & Skottun (1987) que demonstraram decréscimo significativo nos limiares de vernier com o aumento da frequência espacial. Os limiares eletrofisiológicos de vernier obtidos com o presente trabalho mostraram-se paralelos aos dados psicofísicos em função das frequências espaciais em ambos os protocolos. Os limiares no 1F1 também demonstraram redução significativa com o aumento da frequência temporal em altas frequências espaciais
The research was directed at establishing a spatiotemporal map of human cortical vernier responses. The use of swept-parameter, steady state visual evoked potential (sweep VEP, or sVEP) provides efficient and sensitive measurement of vernier thresholds with which to begin to examine cortical vernier responses over the spatio-temporal parameter space. The vernier responses were evaluated in relation to the hypothesis that the magnocellular (M) but not parvocellular (P) ganglion cell retinal output forms the neural input to cortex that is used to derive vernier (high precision localization task - Lee et al., 1990; Lee et al., 1995). Methods: Human cortical vernier responses were measured using the sweep visual evoked potential (sVEP). Vernier offsets are introduced into a square wave grating producing interleaved vertical columns of moving and static bars. Binocular measurements of the vernier acuity were made using high contrast (64%) gratings as a function of 3 temporal frequencies (TF = 3, 6 and 15 Hz) and 2 spatial frequencies (SF = 1 and 8 c/g). Measurements were also made at low contrast (8%) as a function of 3 temporal frequencies (3, 6 and 10Hz) and 3 spatial frequencies (1, 2 and 8c/g) using the sVEP. The POWER DIVA system uses the recursive least squares to extract the response amplitude and phase at selected harmonics of the stimulus frequency. We analyzed the evoked potentials at the first (1F1 fundamental) and second (2F1) harmonics. Based on prior research, we take the 1F1 component to be the specific response to the periodic vernier onset/offset, while the 2F1 component reflects local relative motion responses. We checked this assumption by also measuring sVEPs using a motion control protocol in which equivalent displacement amplitudes were presented in and identical stimulus array, but with the displacements being completely symmetrical alternations between two states of misalignment (grating elements were never aligned). To ensure that the amplitude data used for the regression and extrapolation to threshold is really a response to stimulus instead of noise, POWER DIVA calculates, for each 1-second analysis window (time bin), a local noise amplitude. The mean noise amplitude across 10 analysis bins is used to calculate the signal to noise ratio for each time bin. Only signals with a signal to noise ratio > 3 were considered as a response. The vector average of at least 8 trials was used to determine thresholds. Results: The data are consistent with some comparable prior psychophysical data, especially data from Bradley & Skottun (1987) who showed significant decrease in the vernier thresholds with the increase of spatial frequency. Our cortical (sVEP) vernier thresholds paralleled the psychophysical data as a function of SF in both protocols. The 1F1 (vernier) thresholds also exhibited a significant decrease with increase of temporal frequency at high SF
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5

Shah, Neet. "Visual Field Analysis for Functional Visual Loss." Thesis, The University of Arizona, 2018. http://hdl.handle.net/10150/626887.

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6

Chronicle, Edward Peter. "Visual discomfort and visual dysfunction in migraine." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283940.

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7

Nelson, Patricia. "Visual Function and Visual Disability in Glaucoma." Thesis, Heriot-Watt University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518609.

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8

Candido, Jacqueline P. Haslam Elizabeth L. "Visual impairment in a visual medium perspectives of online learners with visual impairments /." Philadelphia, Pa. : Drexel University, 2008. http://hdl.handle.net/1860/2932.

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9

Senos, Ricardo Jorge Grilo Marques. "Repensar a educação visual, falando de contemporaneidade: o propósito da literacia visual." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14757.

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Анотація:
Mestrado em Ensino de Artes Visuais no 3º Ciclo do Ensino Básico e no Ensino Secundário
A evolução das sociedades contemporâneas, na qual a comunicação visual tem papel de destaque através dos mais variados aparatos tecnológicos, criou um novo e complexo contexto de informação e uma consequente necessidade de descodificação e interpretação dessa mesma realidade. Neste sentido, considerando a escola como uma das organizações de maior relevância na transmissão de saberes, este estudo pretende alertar para a importância da Educação Visual, partindo das concepções relativas à literacia visual, condição imprescindível ao desenvolvimento das futuras gerações. O relatório tem por base um caso prático, formalizado numa unidade de trabalho implementada numa turma do 8ºano de escolaridade da Escola Secundária João Carlos Celestino Gomes, em Ílhavo, e que implica o desenvolvimento de uma marca e respetivo logótipo, com o objetivo de reforçar o papel da literacia visual, decisiva para a construção de cultura visual nos jovens alunos. A pesquisa demonstra a imprescindibilidade dessas mesmas competências, enquanto ferramenta pedagógica, integradora de vários saberes, capaz de despertar vontades mais autónomas, críticas e empreendedoras enquanto assistimos às metamorfoses vertiginosas da contemporaneidade.
The evolution of contemporary societies, where visual communication plays a prominent role through various technological devices, has created a new and complex information context, and a consequent need for decoding and interpretation of that reality. In this sense, considering the School as one of the most significant organizations in the transmission of knowledge, this study aims to draw attention to the importance of Visual Education, based on the conceptions related to visual literacy, an essential condition to the development of future generations. The report is based on a practical case, formalized in a work unit implemented in a 8th grade class at Secondary School João Carlos Celestino Gomes, in Ílhavo, which leads to the development of a brand and respective logo with the aim of strengthening the role of visual literacy, decisive for building a visual culture in young students. The research shows the absolute need of these same skills, while educational tool, integrating multiple knowledges and capable of awakening more autonomous, critical and entrepreneurial wills, while we watch the vertiginous metamorphoses of contemporaneity.
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10

Oliveira, Jociele Lamper de. "Arte contemporânea, cultura visual e formação docente." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/27/27160/tde-19112010-092340/.

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Анотація:
Esta pesquisa foi desenvolvida no Programa de Pós-Graduação em Artes Visuais, na Área de Concentração Teoria, Ensino e Aprendizagem da Arte, na Linha de Pesquisa Fundamentos do Ensino e Aprendizagem da Arte, da Escola de Comunicações e Artes da Universidade de São Paulo. Objetivou investigar aspectos que decorrem das inter-relações entre Artes Visuais, cultura visual e formação docente, que compreendem a prática educativa e a prática artística. A partir destes pontos de tensões, aponta-se a imagem da moda em confluência com o ensino de arte na prática do estágio curricular supervisionado, podendo sugerir e impulsionar formas de ensino e aprendizagem autônomas e colaborativas na formação do artista/professor/pesquisador em Artes Visuais. Aborda-se uma reflexão teórica voltada para a cultura visual, bem como para as derivações sobre arte relacional e processo criativo. Desta forma a pesquisa pautou-se sobre alguns aspectos reflexivos da artografia, bem como sobre da arte relacional, entendendo um conjunto de práticas artísticas que tomam como ponto de partida (teórico e prático) as relações humanas e seu contexto social.
This research was developed in the Graduation Program in Visual Arts of the Arts and Communication School of the University of Sao Paulo, concentration area of Art Theory, Teaching and Learning, and research interest The Fundamentals of Art Teaching and Learning. It aimed to investigate the aspects that elapse from the interrelations among Visual Arts, Visual Culture and Faculty Formation, which comprehend the educational and artistic practice. From these tension points, it aims the fashion image in confluence with the art teaching in the practice of the supervised internship, being able to suggest and instigate collaborative and autonomous ways of teaching and learning in the formation of the artist/teacher/researcher in the Visual Arts. It approaches a theoretical reflection about the visual culture, as well as the derivations of the relational art and the creative process. Thus, this research was based on some reflexive aspects of the artography and the relational art, comprehending a group of artistic practices that take as initial point (theoretical and practical) the human relations and their social context.
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11

Khalil, Nofal Mohammed. "Investigations of visual function in migraine by visual evoked potentials and visual psychophysical tests." Thesis, Imperial College London, 1991. http://hdl.handle.net/10044/1/8336.

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12

Costa, Patrícia Folgado Bargado. "Análise visual da paisagem. Caso de Estudo: concelho de Almada." Master's thesis, ISA, 2010. http://hdl.handle.net/10400.5/3111.

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Анотація:
Mestrado em Arquitectura Paisagista - Instituto Superior de Agronomia
The interest for the subject, “Visual Analysis of the Landscape in the Municipality of Almada”, emerged from the perception that projects don´t generally meet the needs of the populations, but instead they meet the personal preferences of the designer. The aim of this work is to introduce public opinion as a tool in the design process. Although the general public doesn´t possess the technical knowledge, making the intervention of the designer essential, they do possess the practical knowledge of the dynamics, needs and the most valuable assets of the landscape that surrounds the areas where they live or work. As a case study I chose the Municipality of Almada, from which I took the seven most representative photos and then elaborated an inquiry to its population. In an inquiry, these pictures were to be ordered by preference by the inquired, asking them to make the visual analysis of the municipality and revealing what kind of landscapes they most and least like. It was possible to conclude that although the urban expansion engulfed the natural landscape, involving the population in an insalubrious environment, people still prefer landscapes with natural elements, like water or vegetation. Landscapes with cultural heritage are also of great importance, for they represent the identity of the population or of the nation itself.
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13

Havelka, Jelena. "Phonological and visual factors in visual word recognition." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324326.

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14

Xue, Tianfan. "Exploiting visual motion to understand our visual world." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/113978.

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Анотація:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 115-126).
Motion is important for understanding our visual world. The human visual system relies heavily on motion perception to recognize the movement of objects, to infer the 3D geometry of a scene, and to perceive the emotions of other people. Modern computer vision systems also use motion signals extracted from video sequences to infer high-level visual concepts, including human activities and abnormal events. Both human and computer visual systems try to perceive changes in the 3D physical world through its 2D projection, either on the image plane or on our retinas. The observed 2D pixel movement is the result of several factors. First, the image sensor might move, inducing egocentric motion, even when the scene is static. Second, the medium between objects and a camera might change and affect how light transmits from the objects to the sensor, like the shimmering in a hot-road mirage. Finally, the objects in a scene might move, either actively, like a person walking along a street, or passively, like a tree branch that is vibrating due to wind. All of these movements reveal information about our visual world. In this dissertation, we will discuss how to infer physical properties of our visual world from observed 2D movement. First, we show how to infer the depth of a scene from egocentric motion and use this to remove undesired visual obstructions. Second, we relate the slight wiggling motion due to refraction to the movement of hot air and infer the location and velocity of the airflow. Last, we illustrate how to infer the physical properties of objects, such as their deformation space or internal structure, from their motion.
by Tianfan Xue.
Ph. D.
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15

Owens, Andrew (Andrew Hale). "Learning visual models from paired audio-visual examples." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/107352.

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Анотація:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 93-104).
From the clink of a mug placed onto a saucer to the bustle of a busy café, our days are filled with visual experiences that are accompanied by distinctive sounds. In this thesis, we show that these sounds can provide a rich training signal for learning visual models. First, we propose the task of predicting the sound that an object makes when struck as a way of studying physical interactions within a visual scene. We demonstrate this idea by training an algorithm to produce plausible soundtracks for videos in which people hit and scratch objects with a drumstick. Then, with human studies and automated evaluations on recognition tasks, we verify that the sounds produced by the algorithm convey information about actions and material properties. Second, we show that ambient audio - e.g., crashing waves, people speaking in a crowd - can also be used to learn visual models. We train a convolutional neural network to predict a statistical summary of the sounds that occur within a scene, and we demonstrate that the visual representation learned by the model conveys information about objects and scenes.
by Andrew Owens.
Ph. D.
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16

Ngo, Mary Kim. "Facilitating visual target identification using non-visual cues." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:6e05bfc4-f049-43a3-8ecc-4db38f8cbb09.

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Анотація:
The research presented in this thesis was designed to investigate whether and how the temporal synchrony and spatial congruence of non-visual cues with visual targets could work together to improve the discrimination and identification of visual targets in neurologically-healthy adult humans. The speed and accuracy of participants’ responses were compared following the presence or absence of temporally synchronous and/or spatially congruent or incongruent auditory, vibrotactile, and audiotactile cues in the context of dynamic visual search and rapidly-masked visual target identification. The understanding of the effects of auditory, vibrotactile, and audiotactile cues derived from these laboratory-based tasks was then applied to an air traffic control simulation involving the detection and resolution of potential conflicts (represented as visual targets amidst dynamic and cluttered visual stimuli). The results of the experiments reported in this thesis demonstrate that, in the laboratory-based setting, temporally synchronous and spatially informative non-visual cues both gave rise to significant improvements in participants’ performance, and the combination of temporal and spatial cuing gave rise to additional improvements in visual target identification performance. In the real-world setting, however, only the temporally synchronous unimodal auditory and bimodal audiotactile cues gave rise to a consistent facilitation of participants’ visual target detection performance. The mechanisms and accounts proposed to explain the effects of spatial and temporal cuing, namely multisensory integration and attention, are examined and discussed with respect to the observed improvements in participants’ visual target identification performance.
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17

Li, Qi. "Interactions between Visual Attention and Visual Working Memory." Kyoto University, 2015. http://hdl.handle.net/2433/199403.

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Анотація:
Kyoto University (京都大学)
0048
新制・課程博士
博士(人間・環境学)
甲第19079号
人博第732号
新制||人||176(附属図書館)
26||人博||732(吉田南総合図書館)
32030
京都大学大学院人間・環境学研究科共生人間学専攻
(主査)教授 齋木 潤, 教授 船橋 新太郎, 准教授 月浦 崇
学位規則第4条第1項該当
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18

Pereira, Fabio Irigon. "High precision monocular visual odometry." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/183233.

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Анотація:
Extrair informação de profundidade a partir de imagens bidimensionais é um importante problema na área de visão computacional. Diversas aplicações se beneficiam desta classe de algoritmos tais como: robótica, a indústria de entretenimento, aplicações médicas para diagnóstico e confecção de próteses e até mesmo exploração interplanetária. Esta aplicação pode ser dividida em duas etapas interdependentes: a estimação da posição e orientação da câmera no momento em que a imagem foi gerada, e a estimativa da estrutura tridimensional da cena. Este trabalho foca em técnicas de visão computacional usadas para estimar a trajetória de um veículo equipado com uma câmera, problema conhecido como odometria visual. Para obter medidas objetivas de eficiência e precisão, e poder comparar os resultados obtidos com o estado da arte, uma base de dados de alta precisão, bastante utilizada pela comunidade científica foi utilizada. No curso deste trabalho novas técnicas para rastreamento de detalhes, estimativa de posição de câmera, cálculo de posição 3D de pontos e recuperação de escala são propostos. Os resultados alcançados superam os mais bem ranqueados trabalhos na base de dados escolhida até o momento da publicação desta tese.
Recovering three-dimensional information from bi-dimensional images is an important problem in computer vision that finds several applications in our society. Robotics, entertainment industry, medical diagnose and prosthesis, and even interplanetary exploration benefit from vision based 3D estimation. The problem can be divided in two interdependent operations: estimating the camera position and orientation when each image was produced, and estimating the 3D scene structure. This work focuses on computer vision techniques, used to estimate the trajectory of a vehicle equipped camera, a problem known as visual odometry. In order to provide an objective measure of estimation efficiency and to compare the achieved results to the state-of-the-art works in visual odometry a high precision popular dataset was selected and used. In the course of this work new techniques for image feature tracking, camera pose estimation, point 3D position calculation and scale recovery are proposed. The achieved results outperform the best ranked results in the popular chosen dataset.
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19

Danelljan, Martin. "Visual Tracking." Thesis, Linköpings universitet, Datorseende, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-105659.

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Анотація:
Visual tracking is a classical computer vision problem with many important applications in areas such as robotics, surveillance and driver assistance. The task is to follow a target in an image sequence. The target can be any object of interest, for example a human, a car or a football. Humans perform accurate visual tracking with little effort, while it remains a difficult computer vision problem. It imposes major challenges, such as appearance changes, occlusions and background clutter. Visual tracking is thus an open research topic, but significant progress has been made in the last few years. The first part of this thesis explores generic tracking, where nothing is known about the target except for its initial location in the sequence. A specific family of generic trackers that exploit the FFT for faster tracking-by-detection is studied. Among these, the CSK tracker have recently shown obtain competitive performance at extraordinary low computational costs. Three contributions are made to this type of trackers. Firstly, a new method for learning the target appearance is proposed and shown to outperform the original method. Secondly, different color descriptors are investigated for the tracking purpose. Evaluations show that the best descriptor greatly improves the tracking performance. Thirdly, an adaptive dimensionality reduction technique is proposed, which adaptively chooses the most important feature combinations to use. This technique significantly reduces the computational cost of the tracking task. Extensive evaluations show that the proposed tracker outperform state-of-the-art methods in literature, while operating at several times higher frame rate. In the second part of this thesis, the proposed generic tracking method is applied to human tracking in surveillance applications. A causal framework is constructed, that automatically detects and tracks humans in the scene. The system fuses information from generic tracking and state-of-the-art object detection in a Bayesian filtering framework. In addition, the system incorporates the identification and tracking of specific human parts to achieve better robustness and performance. Tracking results are demonstrated on a real-world benchmark sequence.
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20

Lindberg, Erik. "Visual Inductosyn." Thesis, Linköpings universitet, Institutionen för teknik och naturvetenskap, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-97913.

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Анотація:
This is a project where modern visualization techniques are used to create an interactive and animated technical illustration of how the position measuring product Inductosyn works. The project is made on behalf of Inductosyn International, an engineering company in Valhalla, New York. The visualization is focused on the operating principle of the product and the technical benefits of using the product in the two application areas Air Surveillance Radar and Air Defence Systems. The purpose with the project is to create a series of applications the company can use as a complement in marketing to demonstrate the product and visualize its benefits to customers. This report covers the whole process from project background, choice of visualization platform, creating visualization concepts to the implementation and the final results.
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21

Fullerton, Jeanay. "VISUAL STAMP." Master's thesis, University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4017.

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Анотація:
I create images in a painterly manner illustrating a visual dialog, which suggests simultaneous moments, yet are actually a separated collision of moments and time. I have stretched these ideas from a slowed manipulation of time, to a calculated capture of segmented moments. My work undermines the importance of the decisive moment theory. This theory was the catalyst for my new series, VISUAL STAMP. "The decisive moment, it is the simultaneous recognition, in a fraction of a second, of the significance of an event as well as the precise organization of forms which gives that event its proper expression." - Henri Cartier-Bresson I am conveying space and time on a single plane in a similar way to how we perceive, process, and retain information visually. The discarded moments in our perception are what I am interested in capturing. We do not view life in a frozen millisecond. Contemporary modes of perception involve the sensorial experience of viewing thousands of movements in small bursts of time that are often left behind, and forgotten. By layering images I am illustrating gaps from one moment to the next. My interest in using the insignificant event to create an aesthetic has become a personal visual stamp. This series embraces the discarded aspects of our visual interpretation of the objects and places we see in everyday life.
M.F.A.
Department of Art
Arts and Humanities
Studio Art and the Computer MFA
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22

RIBEIRO, LARISSA PINHO ALVES. "VISUAL AUTOBIOGRAPHY." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=30173@1.

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Анотація:
PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
A partir da década de 1980 foi possível observar uma multiplicação de discursos autobiográficos que impregnou os hábitos, costumes e a produção das indústrias culturais e da pesquisa acadêmica. Esse interesse renovado pelas histórias de vida e pela ideia mesmo de vida como reação frente aos anos de inflacionismo teórico e da defesa violenta da impessoalidade, aponta para algo mais que a simples proliferação de formas, e expressa uma tonalidade particular da subjetividade contemporânea. A expansão do biográfico marca um movimento de retorno à problemática do sujeito, não como reafirmação daquele sujeito cartesiano, moderno, mas como continuidade da crítica a esse modelo. É nesse contexto que se insere essa pesquisa, interessada em explorar, de forma pessoal e experimental, formas de compor autobiografias visuais, ou antibiografias, que não aspirem a reconstrução de uma totalidade, a coerência cronológica, ou a afirmação de um eu testemunhal, mas que estejam empenhadas em dar movimento à existência, e não sentido (direção), e que não busque um sentido (significado), mas se colocar sensível. Para tanto, utilizou-se como ferramenta de pesquisa a experimentação artística através do dispositivo fotográfico, observando, através dessa prática, possibilidades de construção e leitura de uma escrita do eu alternativa.
Since 1980 it was possible to notice a multiplication of autobiographical discourses which impregnated the habits, behaviors and production of the cultural industry and the academic research. This renewed interest for life stories and for the very idea of life itself as a reaction against all the years of theoretical inflationism and the violent defense of impersonality, points to something more than just the simple proliferation of forms, and expresses a particular tone of the contemporary subjectivity. The biographical expansion marks a movement of return to the problematic of the subject, not as a restatement of the Cartesian and modern subject, but as a sequence to the critics against this very model. The present research is founded in this context, interested to explore, in a personal and experimental manner, ways to create visual autobiographies, or antibiographies, that don t aim for a full reconstruction, a chronological coherence, or the affirmation of a testimonial self, but rather to invest in putting existence into motion, instead of giving it guidance and to search not for meaning, but becoming sensitive to it. To do so, was used artistic experimentation through photographical devices as a research tool, observing, through this practice, possibilities of producing and reading an alternative self-writing.
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23

Kellogg, Christopher James. "Visual memory." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/108869.

Повний текст джерела
Анотація:
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1993.
Includes bibliographical references (leaves 90-92).
Visual memory supports computer vision applications by efficiently storing and retrieving spatiotemporal information. It is a unique combination of databases, spatial representation and indexing, and temporal representation and indexing. This thesis designs a visual memory architecture that meets the requirements of a number of computer vision applications. It also presents an implementation of part of this design in support of a scene monitoring prototype.
by Christopher James Kellogg.
M.S.
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24

Smithson, Hannah Elizabeth. "Visual masking." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621850.

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25

Heslyk, Oskar. "Visual Assembly." Thesis, KTH, Arkitektur, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-298507.

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Анотація:
The project investigates an aesthetic of assembly. It established a visual expression though exploring the relationship between disassembly and assembly in the context of laminated timbers. These explorations are manifested in a learning institution in relationship to an existing CLT factor in Långshyttan. The project becomes a dynamic celebration of assembly and a continuous learning environment as the building continues to disassemble and reassemble to counter the obsolescent of new technological inventions in a rapidly developing industry driven by industrialization and technological determination.  The new building feeds of the factory for purely disassembled parts in terms of discarded waste and a pure form of assembly in terms of unprocessed CLT blanks. The production of industrial produced mass timber elements has further moved the production of buildings into factories and the erection of buildings at site consist primarily of an assembly of  predesigned parts. Architectural advancements is inseparable from technological paradigms and the production of construction timber should carry with it new architectural expressions.
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26

Ornoff, Theresa. ""Visual Vessels"." VCU Scholars Compass, 2011. http://scholarscompass.vcu.edu/etd/2593.

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Анотація:
In 1989 while our severely ill son lay in our arms my husband and I asked the surgeon what he would do if he were in our shoes. “Play the hand you’re dealt.” he replied. It was not this doctor’s only reference to the gamble life holds for each of us. Based on his advice to us I began to investigate the role that fate and predetermination play in our lives and consequently how much control we have on the outcome of life’s events. A cathartic family portrait piece laid the groundwork for a series of metaphorical portraits as I began to investigate identity. The continued use of identity as my thematic approach has allowed me to record emotional waypoints and personal change throughout my life and to additionally pose questions about what constitutes a portrait. At times this approach thankfully led me to use my art as a visual vessel, a container in which to place my emotional burdens lightening the load while I continued on in my daily life
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27

Bottomley, Richard. "Visual Intimacy." VCU Scholars Compass, 2012. http://scholarscompass.vcu.edu/etd/2664.

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Анотація:
My work is designed to visually intrigue and excite while creating a sense of intimacy with the viewer. The inspiration for my paintings, prints, and mixed media pieces are derived from views of flowers and the female form. Sometimes the flowers and forms are presented separately, sometimes they are combined into single works. I experiment with different media and supports, such as acrylic paint and gel transfers on canvas or Plexiglas, drypoint on Plexiglas, and chalk pastels on wood paneling. Compositionally, I often place light, transparent shapes against dark, opaque grounds to create dramatic contrast. I also use a wide range of values, a vivid and varied color palette, and fine detail to attract my viewer’s attention.
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28

Perez, Wladmir. "Gramática visual." Florianópolis, SC, 2008. http://repositorio.ufsc.br/xmlui/handle/123456789/91497.

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Анотація:
Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção.
Made available in DSpace on 2012-10-23T23:38:53Z (GMT). No. of bitstreams: 1 250234.pdf: 5259318 bytes, checksum: dedeb3e3e876df8b0e69d70823c44368 (MD5)
Com uma presença quase exclusiva nos meios de comunicação, a imagem como representação visual perpassa todas as áreas e segmentos da sociedade. Representa mais do que um recurso estético no sentido alegórico, assumindo um papel decisivo na construção de significados. O objetivo deste estudo foi identificar os aspectos teóricos e os elementos formais discursivos da representação visual a fim de possibilitar a elaboração de uma sintaxe gramático-visual. Nesse sentido, o universo da Linguagem Visual foi explorado no intuito de entender a dimensão que a estruturação da imagem como linguagem ocupa no processo de comunicação. Este estudo partiu da premissa básica de que independentemente de a imagem como representação visual ter um caráter polissêmico, sua estruturação - a partir do que denominamos de Gramática Visual sustentada a partir das teorias da semiótica, gestalt e estética -, possibilitará reduzir essa polissemia e, conseqüentemente, aumentar o grau de compreensão dos conteúdos das mesmas, portanto, aumentando o grau de objetividade pretendido pelos que se utilizam dela como meio de comunicação. Como base de sustentação às proposições aqui apresentadas, as teorias estéticas, cognitivas, semióticas e filosóficas indicaram os caminhos necessários na constituição de uma Linguagem Visual estruturada. Além disso, acreditamos que a ordenação de determinados conceitos, a revisão de outros e a inserção de novos proporcionou a apresentação de um modelo, que poderemos denominar de "arcabouço" de uma gramática. An almost exclusive presence in the media, the image as a visual representation pervades all areas and segments of society. It represents more than an aesthetic resource in the allegorical sense, assuming a decisive role in the construction of meanings. The objective of this study was to identify the theoretical aspects and discursive formal elements of visual representation in order to enable the elaboration of a grammatical-visual syntax. In this sense, the universe of the Visual Language had been exploited in order to understand the dimension that the structuring of the image as language occupies in the communication process. This study starts from the basic premise that regardless the fact that image as representation has a polysemous character, its structuration - on the basis of what we call Visual Grammar sustained by semiotics, gestaltic and aesthetics theories - would reduce the polysemy and, consequently, increase the level of understanding of its contents, increasing the degree of objectivity intended by those that make use of it as a means of communication. It assumes an aesthetic, cognitive, philosophical and semiotic reflection as a basis and path in the constitution of a structured Visual Language. Furthermore, we believe that the organization of certain concepts, the review of other and the inclusion of new ones provided the presentation of a model we can call the "framework" of a grammar.
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29

Camêlo, Francisco das Chagas. "Conversações com Baravelli: o ofício contínuo do pensar e do fazer." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/27/27159/tde-27022015-150624/.

Повний текст джерела
Анотація:
A presente pesquisa é apresentada em forma de trabalho artístico equivalente à tese de doutorado, como proposição de final de curso, que se sustenta nas escolas superiores, com o título, Conversações com Baravelli: o ofício contínuo do pensar e do fazer. A escolha pela conversação como fio condutor do trabalho acadêmico, a partir de procedimentos didáticos, apresenta-se como proposta acadêmica, justificando-se como o diálogo com o artista, por meio de aplicação de questionário semi-estruturado. Conversações com Baravelli: o ofício contínuo do pensar e do fazer, que se apresenta em duas peças - uma primeira descritiva e outra com imagens/textos-, pretende investigar os elementos visuais compositivos, a formação do artista, e seus procedimentos de criação. Esta pesquisa divide-se em cinco capítulos, a saber: Os elementos significativos na formação do trabalho de Luiz Paulo Baravelli; Os conceitos de desenho; Luiz Paulo Baravelli e seu tempo histórico; Os cadernos de anotações visuais e a obra entregue ao público, e Algumas contribuições de Luiz Paulo Baravelli. Nos capítulos, apresentam-se os processos poéticos do artista, a seleção dos documentos visuais e a investigação dos seus conceitos. A pesquisa estrutura-se na área de concentração das poéticas visuais e na linha de pesquisa dos processos de criação em artes visuais. O aporte teórico adotado sustenta-se em leituras de pesquisadores da área e inserção de citações ao longo dos capítulos; os autores que fundamentam a escrita são estudiosos com trabalhos desenvolvidos em linha de pesquisa dos processos de criação em artes visuais, nas áreas da comunicação e história da arte dialogando com a pesquisa. Depoimentos e citações de Baravelli fazem parte do corpo do trabalho, e foram selecionadas em entrevistas, declarações cedidas pessoalmente, e artigos da imprensa. Pretende-se com este trabalho acadêmico contribuir para a continuidade da pesquisa visual na área das poéticas visuais, especialmente com o registro da produção de Baravelli, animando a investigação e a produção visual, como fonte de conhecimento.
This research is presented in a format of artistic work equivalent of doctorate thesis, as proposal for the conclusion of course, based in the specialists studies, with the title of Conversações com Baravelli: o ofício contínuo do pensar e do fazer (Conversations with Baravelli: the continuous task of thinking and performing) . The choice of conversation as theme of this paperwork, through didactic procedures is an academic proposal, legitimating the dialogue with the artist, through a semi-structured questionnaire. Conversações com Baravelli: o ofício contínuo do pensar e do fazer (Conversations with Baravelli: the continuous task of thinking and performing), that is presented in two parts - the first one is descriptive and the other with images/texts, has the aim of investigating the visual compositional elements, learning process of the artist and his creation procedures. This research is divided into five chapters, as follows: Os elementos significativos na formação do trabalho de Luiz Paulo Baravelli (The significative elements in the performing process of Luiz Paulo Baravelli); Os conceitos de desenho (The design concepts); Luiz Paulo Baravelli e seu tempo histórico (Luiz Paulo Baravelli and his historical time); Os cadernos de anotações visuais e a obra entregue ao público (The visual notebooks and the work offered to the public) and Algumas contribuições de Luiz Paulo Baravelli (Some contributions of Luiz Paulo Baravelli). In the chapters are presented the poetics processes of the artist, the selection of visual documents and investigation of his concepts. The research is based in the area of the concentration of visual poetic and in the creation process in visual arts. The theoretical contribution adopted is warranted in the readings of researchers and insertion of citations over chapters, the authors who substantiate the writing are specialists with academic Works developed in creation studies of visual art processes in the areas of communication and history of art dialoguing with the present research. Testimonials and citations of Baravelli complement the paperwork and were selected in interviews, personal pronouncements and press articles. The aim of this paperwork is to contribute to the continuity of research in the area of visual poetic, especially with the performance records of Baravelli, encouraging the investigation of visual production as source of knowledge.
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30

Antunes, Sérgio Bruno Canha. "Educação visual num mundo codificado." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/12952.

Повний текст джерела
Анотація:
Mestrado em Ensino de Artes Visuais no 3º Ciclo do Ensino Básico e no Ensino Secundário
Este trabalho é o resultado das observações e reflexões realizadas no âmbito da Prática de Ensino Supervisionada com alunos do 8º ano na disciplina de Educação Visual. A investigação foi orientada no sentido de recolher dados em relação à capacidade dos alunos em descodificarem imagens. Para tal foram construídas duas unidades de trabalho: Projeto Pictogramas e esPicassar a Guernica. Duas unidades de trabalho que procuraram expor os alunos a dois processos de comunicação que se caracterizam pelo recurso à imagem: a comunicação para massas através de códigos visuais universais e a obra de arte enquanto dispositivo de comunicação individual e de motivações pessoais. Este trabalho procurou também questionar a tentativa do homem em procurar universalizar a comunicação através de representações de imagens simplificadas, e discutir qual o contributo da disciplina de Educação Visual para a formação do aluno num mundo cada vez mais caracterizado pela interatividade e virtualidade.
This work is the result of observations and reflections carried out within the framework of the Supervised Teaching Practice with 8th grade students in Visual Education. The research was orientated to collect information about the ability of students to decode images. For this purpose two work projects were created: Projeto Pictogramas and esPicassar a Guernica. Two exercises that sought to expose students to two communication processes characterized by the use of image: mass communication through universal visual codes, and the work of art as communication device of individual and personal motivations. This study also sought to question man's attempt to seek universal representations of the world, and discuss what is the contribution of Visual Education for the education of students in a world increasingly characterized by interactivity and virtuality.
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31

Thulin, Nilsson Linnea. "The Role of Primary Visual Cortex in Visual Awareness." Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-11623.

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Анотація:
Despite its great complexity, a great deal is known about the organization and information-processing properties of the visual system. However, the neural correlates of visual awareness are not yet understood. By studying patients with blindsight, the primary visual cortex (V1) has attracted a lot of attention recently. Although this brain area appears to be important for visual awareness, its exact role is still a matter of debate. Interactive models propose a direct role for V1 in generating visual awareness through recurrent processing. Hierarchal models instead propose that awareness is generated in later visual areas and that the role of V1 is limited to transmitting the necessary information to these areas. Interactive and hierarchical models make different predictions and the aim of this thesis is to review the evidence from lesions, perceptual suppression, and transcranial magnetic stimulation (TMS), along with data from internally generated visual awareness in dreams, hallucinations and imagery, this in order to see whether current evidence favor one type of model over the other. A review of the evidence suggests that feedback projections to V1 appear to be important in most cases for visual awareness to arise but it can arise even when V1 is absent.
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32

Wong, Solomon Kim-Nung Psychology Faculty of Science UNSW. "Linking visual preferences and visual sensitivity to image structure." Awarded by:University of New South Wales. Psychology, 2009. http://handle.unsw.edu.au/1959.4/44842.

Повний текст джерела
Анотація:
The statistical structure of natural images has sparked interest in regards to both visual processing of such images and the aesthetic responses they elicit. We bring together these two lines of research under the simple proposition that early visual processing, more specifically visual sensitivity, may mediate visual preferences. In our first set of experiments, we measured both visual preference and visual sensitivity in the same observers, using patterns varying in the slope of their amplitude spectrum. Our results found similar functions for both variables, supporting our hypothesis. In a second set of experiments, we investigated the same question with regards to simple spatial frequency variations, and found even more convincing results. We conclude that early visual processing is implicated in visual preference, supporting the recently emerging sensory-based approaches to understanding visual preference.
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33

Sanderson, Mariana Welly. "Effects of visual degradation on audio-visual speech perception." Thesis, Birkbeck (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404941.

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Анотація:
Audio-visual speech recognition is considered to be a dynamic process that uses auditory and complementary visual speech cues. These are the products of the stream of timed and targeted movements of the articulators in the vocal tract used to produce speech. If the visual aspect of speech is absent or degraded, speech recognition in noise may deteriorate; this was used as a tool to investigate the visual aspect of speech recognition in the following experiments. A series of shadowing and recall experiments assessed the effects of frame rate (temporal) and greyscale level (spatial) variations to the visual aspect of audio-visual presentations of sentences spoken in noisy backgrounds by three, evenly illuminated, speakers. There was a significant decline in shadowing accuracy as the frame rate of presentation fell that was related to the importance of temporal synchrony in audiovisual speech. Shadowing and recall experiments, with recordings from one speaker in two illumination conditions and two greyscale levels, revealed that performance accuracy depended on level of illumination in both tasks, for the audio-visual experimental condition and the audio-alone control condition. Moreover in poor illumination, there was significantly less accurate recall performance at the lower greyscale level. This was related to level of spatial facial information that may be used in speech recognition. Shadowing and recall accuracy of sentence's keywords was related to their degree of visible speech-related movement. Audio-visual shadowing accuracy varied little across the range of movements, but audio-alone shadowing accuracy declined significantly as the degree of movement increased. Visual and auditory target characteristics of words associated with differing audio-visual advantage and degrees of visual movement were determined. The findings were considered in the context of a dynamic model of speech processing, which is dependent on patterns of the timings and targets of the auditory and visual speech signals.
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34

McAulay, Ian Charles. "Visual descriptors : a design tool for visual impact analysis." Thesis, University of Plymouth, 1988. http://hdl.handle.net/10026.1/2401.

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Анотація:
This study is concerned with the development of a practical and effective form of computer-aided analysis of the visual impact of building development in rural areas. Its contribution is fourfold. Firstly, a conceptual model has been developed for the process of seeing in the context of visual impact analysis. Secondly, a mathematical model for a consistent series of visual descriptors has been devised. Thirdly, a suitable design tool has been devised to make use of visual descriptors in visual impact analysis. Fourthly, visual descriptors have actually been implemented as computer software. The concept of visual impact analysis is defined and placed within the wider context of landscape research. The problems faced by a designer in the context of visual impact analysis are identified and the concept of a 'design tool' is introduced and defined. A number of existing computer software packages, intended or used for visual impact analysis, are reviewed critically. The concept of 'visual descriptors' as measures to be used by designers is introduced and examined critically. A conceptual model is presented for the process of seeing in the context of visual impact analysis. A range of possible measures for use as visual descriptors is presented and developed further into a series of precise definitions. A method of implementing visual descriptors is presented together with formal algorithms for the derivation of eight visual descriptors. A software package incorporating these descriptors is presented and verification and case studies of its use carried out. Visual descriptors, as implemented, are assessed for their effectiveness as a design tool for visual impact analysis.
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35

Sandy, Shiva S. (Shiva Sean) 1976. "Visual discussions : a visual representation of threaded discussion groups." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/46256.

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Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.
Includes bibliographical references (leaves 39-41).
This is an M.Eng thesis, based on software development work done in collaboration with Lotus Development Corp. In this project we are creating a visual overview of ongoing threads of a discussion database. This will allow users to quickly focus their attention to relevant areas of areas in a large information space.
by Shiva S. Sandy.
S.B.and M.Eng.
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36

King, Michael J. "The Capacity of Visual Working Memory During Visual Search." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1586876852806965.

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37

Guo, Dalu. "Attention Networks in Visual Question Answering and Visual Dialog." Thesis, The University of Sydney, 2021. https://hdl.handle.net/2123/25079.

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Attention is a substantial mechanism for human to process massive data. It omits the trivial parts and focuses on the important ones. For example, we only need to remember the keywords in a long sentence and the principal objects in an image for rebuilding the sources. Therefore, it is crucial to building an attention network for artificial intelligence to solve the problem as human. This mechanism has been fully explored in the text-based tasks, such as language translation, reading comprehension, and sentimental analysis, as well as the visual-based tasks, such as image recognition, object detection, and action recognition. In this work, we explore the attention mechanism in the multi-modal tasks, which involve the inputs of both text and image, i.e. visual question answering and visual dialog. It involves three vital components in both tasks, the input question (with history for visual dialog), the given image, and the generated answers. Therefore, three kinds of relationships should be investigated step by step to solve the problem. We first build the attention between words and objects for generating the representation of them, followed by the relationship between the representation and the answers if the general word embedding does not work properly, and the relationship between the representation and the attributes of answers comes last for few-shot learning. First, the bilinear graph networks revisit the relationship between the words from question and objects for image in the visual question answering task from a graph perspective. The classical bilinear attention networks build a bilinear attention map to extract the joint representation of words and objects but lack fully exploring the relationship between words for complex reasoning. In contrast, our networks model the context of the joint embeddings of words and objects. Two kinds of graphs are investigated, namely image-graph and question-graph. The image-graph transfers features of the detected objects to their related query words, enabling the output nodes to have both semantic and factual information. The question-graph exchanges information between these output nodes from image-graph to amplify the implicit yet important relationship between objects. These two kinds of graphs cooperate with each other, and thus our resulting model can model the relationship and dependency between objects, which leads to the realization of multi-step reasoning. Then, our novel image-question-answer synergistic network values the role of the answer for precise visual dialog. We extend the traditional one-stage solution to a two-stage solution. In the first stage, candidate answers are coarsely scored according to their relevance to the image and question pair. Afterward, in the second stage, answers with high probability of being correct are re-ranked by synergizing with image and question. Finally, we propose to learn the representations of attributes from the answers with enough data, which are later composed to constrain the learning of the few-shot ones. We generate the few-shot dataset of VQA with a variety of answers and extract their attributes without any human effort. With this dataset, we build our attribute network to disentangle the attributes by learning their features from parts of the image instead of the whole one.
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38

Roper, Robyn. "An investigation of the impact of visual culture on visual arts practice and visual arts education." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2005. https://ro.ecu.edu.au/theses/620.

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This research project is based on the premise that school students have a right to an education that assists them to "develop a sense of personal meaning and identity, and be encouraged to reflect critically on the ways in which that occurs." (Curriculum Frameworks, 1998, Values, Statement 2.2 Personal meaning: 325). Not only should education offer students a sense of well being, it should make a difference to their lives and foster an appetite for life long learning. A key ingredient that makes for a rich, fulfilling and rewarding life, is an understanding of visual culture, that according to Freedman (2003:1), "inherently provides context for the visual arts and points to the connections between popular and fine arts forms".
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39

Franz, Volker. "The relationship between visually guided motor behavior and visual perception." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=961452811.

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40

Loncomilla, Zambrana Patricio Alejandro. "Generación Automática de Landmarks Visuales Naturales Tridimensionales para Slam Visual." Tesis, Universidad de Chile, 2011. http://www.repositorio.uchile.cl/handle/2250/102620.

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En los métodos actuales de SLAM visual, los mapas son representados mediante landmarks puntuales. Como la observación de un landmark puntual entrega sólo información angular sobre la cámara, se debe estimar una matriz de covarianza que considere todos los puntos para poder converger a una escala global. Sin embargo, como la complejidad computacional asociada al trabajo con matrices de covarianza crece de una forma cuadrática respecto al número de landmarks, la cantidad máxima de puntos con los cuales se puede trabajar n tiempo real está limitada a unos cientos. En este trabajo se propone un sistema de SLAM visual basado en el uso de los denominados landmarks cuerpo rígido. Un landmark cuerpo rígido representa la pose completa 6D (posición y orientación) de un cuerpo rígido en el espacio, y la observación de uno de estos landmarks proporciona información completa acerca de la pose de una cámara móvil. Cada landmarks cuerpo rígido es creado a partir de un conjunto de N landmarks puntuales mediante el colapso de 3N componentes del estado en 7 nuevas componentes del estado, además de un conjunto de parámetros que describe la forma del landmark. Los landmark cuerpo rígido son representados y estimados usando puntocuaterniones, los cuales son introducidos en este trabajo. Mediante el uso de los landmarks cuerpo rígido, el tiempo de ejecución del sistema de SLAM puede reducirse hasta un 5.5% a medida que la cantidad de landmarks aumenta. El sistema SLAM propuesto es validado y simulado en secuencias de video reales. El método propuesto puede ser extendido a cualquier sistema de SLAM que se base en el uso de landmarks puntuales, incluyendo aquellos generados mediante sensores láser.
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41

Isenstadt, Samuel M. (Samuel Marc). ""Little Visual Empire" : private vistas and the modern American home." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/9979.

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42

Åhman, Sanna, and Lisa Gustavsson. "Visual merchandise online." Thesis, Högskolan i Borås, Institutionen Handels- och IT-högskolan, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18089.

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Syfte: Studiens syfte är att presentera en struktur för online-baserade modeföretags visuellakommunikation. Utgångspunkten är den fysiska butikens visual merchandise-strategier, sommodifieras för att skapa en modell anpassad till online-perspektiv.Metod: För att besvara vårt syfte undersöktes hur webbshoppar arbetar med sin visuellakommunikation genom en kvalitativ observationsstudie. Fyra webbshoppar observeradesunder en period på två veckor, vid tre olika tillfällen. Observationen utgick från studiens egenmodell där visual merchandise-strategier från den fysiska butiken kodats till ett onlinesammanhang.Ett observations-schema med öppna frågor arbetades fram för att praktisktkunna genomföra observationen på ett strukturerat sätt. Arbetet med observationen skeddeparallellt med analysen som kunde anpassas och påverka varandra. Processen var iterativ ochmodellen modifierades under studiens gång. Vi var medvetna om svårigheterna i attundersöka estetisk utformning, då uppfattningar skiljer sig mellan personer och målgrupper.Resultat: Vår slutsats är att webbshoppars övergripande uppbyggnad är likartad och attgrundläggande struktur är den samma. Samtliga hemsidor har förstasidor som främjarkampanjer och väcker intresse. Alla använder överskådliga produktkategorisidor medstrukturerade rutnät där besökaren lätt kan navigera. Den enskilda produkten presenteras avmycket information och flera bilder. Övergripande används symboler som hjälperkonsumenten att fatta köpbeslut och tillför mervärde till produkten. Det som gör atthemsidorna ändå ser väldigt olika ut beror på deras arbete med den visuellakommunikationen. Webbshoppens visuella bild kommunicerar sidans valda profil genominformativa ledtrådar så besökaren kan bedöma och dra slutsatser.Vår slutsats är att den fysiska butikens visual merchandise-strategier kan användas online menbehöver anpassas till det nya sammanhanget. Den fysiska butikens visual merchandisestrategierkan inte översättas direkt till webbshoppar, men det går att göra en nära tolkning.Studiens modell fungerar väl som verktyg för uppgiften och omfattar alla viktiga delar.Modellen är generell och utgår från den övergripande struktur som samtliga webbshoppar harsom utgångpunkt. Detta gör modellen lätt att använda, både på ett omfattande plan och pådetaljnivå.Originalitet: Vår studie erbjuder ett verktyg som hjälper andra praktiker att gå vidare inomområdet. Vi föreslår att testa vår modell dels på andra webbshoppar för att utvärdera derasvisuella kommunikation, samt dels i uppbyggnaden av en helt ny webbshop. Vår modellkommer från ett annat håll och ger en ny infallsvinkel för exempelvis webbdesigners som intehar erfarenhet från den fysiska butiken.
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43

González, Galleguillos Diego Mauricio. "Estrategias de reconocimiento visual en la percepción del movimiento biológico : exploración visual libre o fijación visual forzada." Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/151367.

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Grado de magíster en neurociencias
Uno de los movimientos complejos con importancia evolutiva en humanos es el movimiento biológico, definido como un conjunto de puntos de alto contraste que siguen un patrón coherente de movimiento y que involucra un nivel de procesamiento complejo que integra la velocidad, la forma de los objetos en movimiento, interpretando acciones, estímulos sociales y emociones. Se proponen tres hipótesis para entender qué estrategias visuales permiten la percepción del movimiento biológico. Por una parte, a través de un seguimiento ocular continuo que explora el movimiento biológico (“por partes”), por otra, a través de un foco de atención local discontinuo que extrapola la percepción del movimiento biológico sin explorarlo (“un todo”) y una última que integra ambas hipótesis. Estas hipótesis plantean vías de procesamiento en dos fases: la primera de movimientos locales que se integran en regiones corticales sensoriales de fragmentos del cuerpo. Y la segunda, de fragmentos que generan representaciones completas en la corteza multimodal. Existe actualmente una discusión abierta acerca de cuál de estas estrategias es prioritaria para la percepción del movimiento biológico. Para ello se determinó qué estrategias de reconocimiento visual son usadas preferentemente para la percepción del MB observando si existen diferencias en el desempeño conductual de la percepción visual del MB, durante la exploración libre comparada con la fijación forzada de un objetivo mediante el uso de un sistema de seguimiento ocular (“eye tracker”). Según hallazgos de este estudio se puede afirmar que en la muestra evaluada para un mejor desempeño de la percepción del movimiento biológico es necesario el uso de estrategias de exploración visual libre, y esta conducta ocular obedece a lugares estratégicos del movimiento biológico según la valencia de este. Estudios futuros de este paradigma podrían incluir registro de actividad de señales corticales como el uso de EEG, tanto en sujetos sanos como en personas con patologías que afecten la percepción de esta tarea, como en pacientes con esquizofrenia.
One of the complex movements with evolutionary importance in humans is the biological movement, defined as a set of high-contrast points that follow a coherent pattern of motion and involve a complex processing level that integrates speed the form of moving objects, interpreting actions, social stimuli and emotions. Three hypotheses are proposed to understand visual strategies allow the perception of biological movement. On the one hand, through follow-up continuous ocular that explores the biological movement ("by parts"). On the other, to through a discontinuous local focus of attention that extrapolates the perception of biological movement without exploring it ("a whole"). And a last one that integrates both hypothesis these hypotheses are ways of processing in two phases: The first of local movements which are integrated into sensory cortical regions of fragments of the body. The second of fragments generate by complete representations in multimodal crust. There is currently an open discussion about which of these strategies is a priority for the perception of biological movement. For this, it was determined which visual recognition strategies are used preferentially for MB perception by observing if there are differences in behavioral performance of MB visual perception. During the scan-free compared with forced fixation of a target by using an ocular tracking system (eye tracker). According to findings of this study it can be said that use sample evaluated for a better performance of the perception of biological movement It is necessary to use free visual scanning strategies, and this ocular behavior is due to strategic location of biological movement according to the valence of this. Future studies of this paradigm could include recording activity of cortical signals such as the use of EEG, Both in healthy subject as in people with pathologies that affect the perception of this task as in patients with schizophrenia.
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44

Nürk, Hans-Christoph. "On the importance of visual determinants in visual word recognition." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=962385433.

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45

Hands, Denise Eva. "Assessing visual preferences for industrial rehabilitation using computerised visual simulation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ47329.pdf.

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46

Al-Bagdady, Mohammad. "Visual development and visual defects in children with Down's syndrome." Thesis, Cardiff University, 2009. http://orca.cf.ac.uk/54944/.

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This thesis investigated the refractive, accommodative and colour vision status of young people with Down's syndrome (DS). Seven separate studies were conducted. Participants were recruited from the Cardiff Down's Syndrome Vision Research Unit. Abnormal refractive development was reported from an early age, and continued through the first 15 years of life. The normal emmetropisation process was re-aligned to leave subjects with hypermetropic errors, with a wide variation in refractive error, at all ages. There was a specific development of oblique astigmatism with age, which may be associated with the reduced palpebral aperture. Parental refractive status was not found to influence that of their children with DS, although such a relationship was found with their typically developing siblings. The cause of the refractive errors was axial in nature in children with DS. However, general physical growth did not have an active influence in shaping these errors. Bifocal spectacles were found to be a successful treatment for reduced accommodation in children with DS. From the study cohort, over 40% of the children were able to effectively discard bifocal wear after gaining accurate accommodation. Children with DS demonstrated their ability to engage in subjective colour vision testing, given that appropriate tests were used. The design of the Mollon-Reffin 'Minimalist' (M-R) colour vision test was found most suitable. This test showed high sensitivity and specificity in comparison to other clinical tests. Using the M-R test, the prevalence of colour vision defects in DS was found to be comparable to that of the general population. The studies have generated optometric guidelines for the clinical care of people with DS which emphasise the importance of frequent routine clinical examination of this population due to the unpredictive nature of their refractive error development. Examination from an early age will allow for the early detection, and prompt management, of visual problems. Bifocal prescription is highly encouraged for those with reduced accommodation, with cessation of wear being decided from on-going assessment of the patient's accommodation after bifocal prescription.
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47

Bühler, Frank Stefan. "Combining visual modelling with visual programming for CORBA component development." Thesis, De Montfort University, 2002. http://hdl.handle.net/2086/4068.

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48

Azevêdo, Adriana Medeiros Sales de. "Mapeamento espacial da atenção visual mobilizada pela via visual ventral." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/42/42137/tde-25032010-145400/.

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O processamento visual se dá por duas vias, Dorsal (localização/movimento) mobilizada por TRS (tempo de reação simples), e Ventral (forma/cor) mobilizada por TER (tempo de reação escolha). Apresentamos uma nova abordagem para se investigar a distribuição dos recursos atencionais. Os métodos psicofísicos vigentes amostram repetidas vezes poucos pontos. Optou-se por amostrar muitos pontos na tela do computador poucas vezes, obtendo-se amostragem de uma grande área. Obteve-se um mapa de detalhamento da distribuição atencional. Experimentos de atenção voluntária: I. Tarefa de TRS, mobilizando a via Dorsal. Na situação de atenção difusa. II. TRE, mobilizando a via Ventral. Os estímulos possíveis diferiam na cor e foram respondidos ao se pressionar um botão, atenção difusa. III. TRE, focando-se a atenção em duas molduras, caracterizando atenção dividida. Os resultados demonstraram um favorecimento do hemicampo inferior para a TRS e um favorecimento do hemicampo superior para TER. Apareceram dois focos na atenção dividida fortalecendo a hipótese da divisão atencional.
Visual processing has two pathways: Dorsal (localization/movement) mobilized for Simple Reaction Time tasks (SRT); Ventral (shape/color) mobilized for Choice Reaction Time tasks (CRT). We presented an approach to investigate visual attentional resources. Usual psychophysical methods sample many times few points. We opted to sample many points few times aiming to enlarge the sampled visual field. It was obtained major details of the attentional distribution. Voluntary attention task: I. SRT, for Dorsal pathway. Stimuli were different in color answered triggering a button, in a diffusion attention paradigm. II. CRT, for Ventral pathway. Stimuli were two different color answered by triggering a button for each color in a diffuse paradigm. III. CRT, experimental subject instructed to focus attention in two frames for a splitted attention paradigm. Results showed anisotropy in the diffuse attention distribution, favouring the lower hemifield for SRT and superior hemifield for CRT. The splitted attention paradigm evidenced the presence of two attentional focuses.
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49

Ardila, Jimenez Silvia. "Analysis of visual responses in the mouse early visual pathway." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/43376.

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Many animals, including humans, rely on visual input to guide their behaviour and interact with their environment. The study of the visual system is prevalent in neuroscience, however, given the highly complex nature of the brain, we are yet to understand the full functionality of the system. In this study, we set out to explore different aspects of visual processing in the mouse early visual pathway, and how they compare to those in other mammals. In this thesis, we study two major brain structures in the early visual pathway, the dorsal lateral geniculate nucleus (dLGN) in the thalamus, and the primary visual area (V1 or area 17) in the cortex. We aim to explore 3 different aspects of visual information processing in these areas. Firstly, the functional response characteristics of single neurons in the visual thalamus. Secondly, whether additional communication channels are used in thalamo-cortical interactions in the mouse. And lastly, the correlation of behaviour within neuronal population activity in visual cortex. We use data from two different experimental paradigms. One involves an anaesthetised preparation, recording extracellular potentials from the visual thalamus in isolation, or from the visual thalamus and the primary visual cortex simultaneously. The second involves an awake preparation in which animals were trained on a 'Go'/'NoGo' discrimination task and extracellular potentials were recorded from the primary visual cortex during behaviour. This project combines time-series analysis and information theoretical methods to analyse high dimensional multi-electrode array recordings. In addition to the analysis of experimental data, we also explore the practical and methodological implications of measuring communication through cross-frequency coupling and propose an alternative method to measure this phenomenon.
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50

Tang-Wright, Kimmy. "Visual topography and perceptual learning in the primate visual system." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:388b9658-dceb-443a-a19b-c960af162819.

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The primate visual system is organised and wired in a topological manner. From the eye well into extrastriate visual cortex, a preserved spatial representation of the vi- sual world is maintained across many levels of processing. Diffusion-weighted imaging (DWI), together with probabilistic tractography, is a non-invasive technique for map- ping connectivity within the brain. In this thesis I probed the sensitivity and accuracy of DWI and probabilistic tractography by quantifying its capacity to detect topolog- ical connectivity in the post mortem macaque brain, between the lateral geniculate nucleus (LGN) and primary visual cortex (V1). The results were validated against electrophysiological and histological data from previous studies. Using the methodol- ogy developed in this thesis, it was possible to segment the LGN reliably into distinct subregions based on its structural connectivity to different parts of the visual field represented in V1. Quantitative differences in connectivity from magno- and parvo- cellular subcomponents of the LGN to different parts of V1 could be replicated with this method in post mortem brains. The topological corticocortical connectivity be- tween extrastriate visual area V5/MT and V1 could also be mapped in the post mortem macaque. In vivo DWI scans previously obtained from the same brains have lower resolution and signal-to-noise because of the shorter scan times. Nevertheless, in many cases, these yielded topological maps similar to the post mortem maps. These results indicate that the preserved topology of connection between LGN to V1, and V5/MT to V1, can be revealed using non-invasive measures of diffusion-weighted imaging and tractography in vivo. In a preliminary investigation using Human Connectome data obtained in vivo, I was not able to segment the retinotopic map in LGN based on con- nections to V1. This may be because information about the topological connectivity is not carried in the much lower resolution human diffusion data, or because of other methodological limitations. I also investigated the mechanisms of perceptual learning by developing a novel task-irrelevant perceptual learning paradigm designed to adapt neuronal elements early on in visual processing in a certain region of the visual field. There is evidence, although not clear-cut, to suggest that the paradigm elicits task- irrelevant perceptual learning, but that these effects only emerge when practice-related effects are accounted for. When orientation and location specific effects on perceptual performance are examined, the largest improvement occurs at the trained location, however, there is also significant improvement at one other 'untrained' location, and there is also a significant improvement in performance for a control group that did not receive any training at any location. The work highlights inherent difficulties in inves- tigating perceptual learning, which relate to the fact that learning likely takes place at both lower and higher levels of processing, however, the paradigm provides a good starting point for comprehensively investigating the complex mechanisms underlying perceptual learning.
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