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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The Fleeting Effects of Retrieval Cue Attributes in the PIER2 Memory Model

Wilbanks, Amie L 13 November 2003 (has links)
Processing Implicit and Explicit Representations (PIER2) is a model of memory that makes predictions about memory performance based on the interaction of known and newly acquired information by studying how implicitly activated associates affect episodic memory. Nelson and Zhang (2000) found a significant effect of cue connectivity in a multiple regression analysis of the variables known to affect cued recall, but at that time no manipulational experiments had studied the cue connectivity effect in the laboratory. The present paper presents a series of three experiments designed to investigate the effect of cue connectivity in the context of the PIER2 memory model to determine the importance of this variable in the prediction of cued recall. Results of the experiments were inconsistent, and a revised regression analysis performed on an updated version of Nelson and Zhang's (2000) cued recall database indicated that cue connectivity was no longer a significant predictor of cued recall performance. It was concluded that PIER2's equations do not need to be modified to include the influence of retrieval cue attributes.
12

Exploring the Role of Prospective Memory in Location-Based Reminders

Wang, Yao 03 May 2017 (has links)
Location-based reminder systems (LBRs) are typically used to remind people to complete a to-do task at a particular location. People use their prospective memory to remember future to-do tasks. However, the current design of LBRs fails to take advantage of human prospective memory theory. In this dissertation, I propose a framework connecting human prospective memory theory with LBRs. My work applies human prospective memory into the technical design of LBRs. The goal of my work is to make the reminder work more consistently with how human memory works. Prospective memory research suggests that encoding of the location and familiarity with the location have an impact on prospective remembering. I conducted two empirical studies to test how this theoretical knowledge applies to LBRs. In one experiment, I hypothesized that if the encoding stage provides a closer match to the retrieval stage in LBRs, then location recognition and task recall should improve at retrieval time. The results indicate that providing a first-person view (street view of the desired location) at the encoding stage benefits prospective remembering the most. Prospective memory theory also suggests that the familiarity with the external cue has a significant influence on prospective remembering. In the second experiment, I hypothesized that familiarity with a location has an impact on the location recognition at the retrieval. The results show that the encoding interface is used differently for familiar and unfamiliar cities and businesses to support recognizing a target location. The findings have implications for the design of future LBRs. I designed an LBR prototype by applying these empirical research findings and conducted a usability evaluation. Future designers of LBR should consider 1) providing more support in matching the encoding stage to the eventual cue in retrieval stage and 2) involving user’s familiarity level with the places at the encoding stage to provide a better user experience. My work showed the importance of using prospective memory theory in the design of LBR systems. / Ph. D.
13

Quantifying the Benefits of Immersion for Procedural Training

Sowndararajan, Ajith 04 August 2008 (has links)
Training is one of the most important and widely-used applications of immersive Virtual Reality (VR). Research has shown that Immersive Virtual Environments (IVEs) are beneficial for training motor activities and spatial activities, but it is unclear whether immersive VEs are beneficial for purely mental activities, such as memorizing a procedure. In this thesis, we present two experiments to identify benefits of immersion for a procedural training process. The first experiment is a between-subjects experiment comparing two levels of immersion in a procedural training task. For the higher level of immersion, we used a large L-shaped projection display. We used a typical laptop display for the lower level of immersion. We asked participants to memorize two procedures: one simple and the other complex. We found that the higher level of immersion resulted in significantly faster task performance and reduced error for the complex procedure. As result of the first experiment we performed a controlled second experiment. We compared two within-subjects variables namely environment and location under various treatments formed by combination of three between-subject variables namely Software Field Of View (SFOV), Physical FOV, Field Of Regard (FOR). We found that SFOV is the most essential component for learning a procedure efficiently using IVEs. We hypothesize that the higher level of immersion helped users to memorize the complex procedure by providing enhanced spatial cues, leading to the development of an accurate mental map that could be used as a memory aid. / Master of Science
14

Cross-functional brain imaging of attention, memory, and executive functions : Unity and diversity of neurocognitive component processes

Marklund, Petter January 2006 (has links)
<p>The central theme of the present thesis revolves around the exploration of similarities and differences in brain activity patterns invoked by the component processes underlying mnemonic, executive and attentional functions. The primary aim was to identify and functionally characterize commonly recruited brain regions in terms of shared component processes, which has been a largely neglected area of research in cognitive neuroscience. The vast majority of functional brain imaging investigations of cognition has focused on delineating differences between cognitive functions or processes, with the purpose of isolating the unique functional neuroanatomy that underlies specific cognitive domains. By contrast, the present thesis builds on the results from three imaging studies that focused primarily on detecting commonalities in functional brain activity across different forms of memory processes. In study I, the imaging data from two positron emission tomography (PET) experiments were re-analyzed to identify common activation patterns associated with nine different memory tasks incorporated across the experiments, three each separately indexing working memory, episodic memory, and semantic memory. A generic prefrontal cortex (PFC) network involving discrete subregions of the left hemisphere located in ventrolateral (BA 45/47), dorsolateral (BA 9/44/46), and frontopolar (BA 10) sectors of PFC, as well as a midline portion of the frontal lobes, encompassing the dorsal part of the anterior cingulate cortex (ACC) (BA 24/32), was conjointly recruited across all tasks. In study II, we used a novel mixed blocked/event-related functional magnetic resonance imaging (fMRI) design, which enables separation of brain responses associated with different temporal dynamics to further investigate commonalities of neural activation across working memory, episodic memory, semantic memory, and attention/vigilance. A similar set of common PFC regions, as that discovered in Study I, was found to elicit overlapping brain activity across all memory tasks, with a subset of regions also activated in the attention/vigilance task. Furthermore, the task-induced brain activity was dissociated in terms of the temporal profiles of the evoked neural responses. A common pattern of sustained activity seen across all memory tasks and the attention task involved bilateral (predominantly right-lateralized) ventrolateral PFC (BA 45/47), and the dorsal ACC (BA 24/32), which was assumed to reflect general processes of attention/vigilance. A pattern of sustained activity elicited in all memory tasks, in the absence of attention-related activity, involved the right frontopolar cortex (BA 10), which was assumed to reflect control processes underlying task set maintenance. In addition, common transient activation evoked in the memory tasks relative to the attention task was found in the dorsolateral (BA 9/44) and ventrolateral (BA 47) PFC, the superior parietal cortex (BA 7), and cerebellum. In study III, a mixed fMRI design was used to assess the degree of common brain activity associated with increased executive demand, which was independently manipulated within episodic and working memory. Unitary control modulations involved a shared tonic executive component subserved by fronto-striatal-cerebellar circuitry, assumed to govern top-down context processing throughout task periods, and a stimulus-synchronous phasic component mediated by the intraparietal sulcus (BA 7), assumed to support dynamic shifting of the ‘focus of attention’ among internal representations. Collectively, the theoretical implications of shared neural mechanisms are discussed, with a special focus on human memory and its multifaceted relationships with attention and executive control functions. Finally, the presented imaging data are used to outline a tentative hierarchical neurocognitive model that attempts to give an account of how different unitary component processes might work together during cognitive task performance.</p>
15

Cross-functional brain imaging of attention, memory, and executive functions : Unity and diversity of neurocognitive component processes

Marklund, Petter January 2006 (has links)
The central theme of the present thesis revolves around the exploration of similarities and differences in brain activity patterns invoked by the component processes underlying mnemonic, executive and attentional functions. The primary aim was to identify and functionally characterize commonly recruited brain regions in terms of shared component processes, which has been a largely neglected area of research in cognitive neuroscience. The vast majority of functional brain imaging investigations of cognition has focused on delineating differences between cognitive functions or processes, with the purpose of isolating the unique functional neuroanatomy that underlies specific cognitive domains. By contrast, the present thesis builds on the results from three imaging studies that focused primarily on detecting commonalities in functional brain activity across different forms of memory processes. In study I, the imaging data from two positron emission tomography (PET) experiments were re-analyzed to identify common activation patterns associated with nine different memory tasks incorporated across the experiments, three each separately indexing working memory, episodic memory, and semantic memory. A generic prefrontal cortex (PFC) network involving discrete subregions of the left hemisphere located in ventrolateral (BA 45/47), dorsolateral (BA 9/44/46), and frontopolar (BA 10) sectors of PFC, as well as a midline portion of the frontal lobes, encompassing the dorsal part of the anterior cingulate cortex (ACC) (BA 24/32), was conjointly recruited across all tasks. In study II, we used a novel mixed blocked/event-related functional magnetic resonance imaging (fMRI) design, which enables separation of brain responses associated with different temporal dynamics to further investigate commonalities of neural activation across working memory, episodic memory, semantic memory, and attention/vigilance. A similar set of common PFC regions, as that discovered in Study I, was found to elicit overlapping brain activity across all memory tasks, with a subset of regions also activated in the attention/vigilance task. Furthermore, the task-induced brain activity was dissociated in terms of the temporal profiles of the evoked neural responses. A common pattern of sustained activity seen across all memory tasks and the attention task involved bilateral (predominantly right-lateralized) ventrolateral PFC (BA 45/47), and the dorsal ACC (BA 24/32), which was assumed to reflect general processes of attention/vigilance. A pattern of sustained activity elicited in all memory tasks, in the absence of attention-related activity, involved the right frontopolar cortex (BA 10), which was assumed to reflect control processes underlying task set maintenance. In addition, common transient activation evoked in the memory tasks relative to the attention task was found in the dorsolateral (BA 9/44) and ventrolateral (BA 47) PFC, the superior parietal cortex (BA 7), and cerebellum. In study III, a mixed fMRI design was used to assess the degree of common brain activity associated with increased executive demand, which was independently manipulated within episodic and working memory. Unitary control modulations involved a shared tonic executive component subserved by fronto-striatal-cerebellar circuitry, assumed to govern top-down context processing throughout task periods, and a stimulus-synchronous phasic component mediated by the intraparietal sulcus (BA 7), assumed to support dynamic shifting of the ‘focus of attention’ among internal representations. Collectively, the theoretical implications of shared neural mechanisms are discussed, with a special focus on human memory and its multifaceted relationships with attention and executive control functions. Finally, the presented imaging data are used to outline a tentative hierarchical neurocognitive model that attempts to give an account of how different unitary component processes might work together during cognitive task performance.
16

Étude électrophysiologique de la mémoire à court terme auditive

Guimond, Synthia 05 1900 (has links)
La présente étude s’intéresse aux mécanismes neuronaux qui sous-tendent la rétention en mémoire à court terme auditive (MCTA) en utilisant la technique des potentiels reliés aux événements (PRE). Dans l’Expérience 1, nous avons isolé une composante de PRE, nommée SAN pour « sustained anterior negativity ». La SAN augmentait en amplitude négative plus le nombre de sons à maintenir en MCTA augmentait. Cet effet de charge était présent, bien que la durée totale des stimuli restait la même entre les conditions. L’effet de charge observé par la SAN dans l’Expérience 1 disparaissait dans l’Expérience 2, où les mêmes sons étaient utilisés, mais où la mémorisation de ceux-ci n’était plus requise. Finalement, dans l’Expérience 3, la tâche de MCTA a été effectuée avec et sans suppression articulatoire durant l'intervalle de rétention. L’effet de charge trouvé dans l’Expérience 1 était de nouveau observé, lorsque les participants faisaient la tâche de suppression articulatoire ou non. Ces résultats suggèrent que la SAN reflète l'activité nécessaire pour le maintien des objets acoustiques dans un système de MCTA qui serait distinct de la répétition phonologique. / We studied the neuronal mechanisms that implement acoustic short-term memory (ASTM) for pitch using event-related potentials (ERP). Experiment 1 isolated an ERP component, the sustained anterior negativity (SAN), that increased in amplitude with increasing memory load in ASTM using stimuli with equal duration at all memory loads. The SAN load effect found in Experment 1, when pitch had to be remembered to perform the task, was absent in Experiment 2 using the same sounds when memory was not required. In Experiment 3 the memory task was performed without or with concurrent articulatory suppression during the retention interval, to suppress rehearsal via an articulatory loop. Load-related effects found in Experiment 1 were found again, whether participants engaged in concurrent suppression or not. The results suggest that the SAN reflects activity required to maintain pitch objects in an ASTM system that is distinct from articulatory rehearsal.
17

Gestão digital do aprendizado pessoal

Silva, Daniel Filisetti Marcos da 03 March 2016 (has links)
Made available in DSpace on 2016-04-29T14:23:42Z (GMT). No. of bitstreams: 1 Daniel Filisetti Marcos da Silva.pdf: 7129185 bytes, checksum: b1e9abb5673705abe337a15914711178 (MD5) Previous issue date: 2016-03-03 / When it comes to digital and internet technology, it comes to mind the access to an infinite world of information. On the other hand, in life, we learn an enormous quantity of knowledge that is stored in our memory and is spread in files, folders and texts, either digital or physical. This thesis proposes to look at this inner immensity of knowledge and to investigate how digital technology can be used to organize, register and access it in an efficient and lasting way. Parallel to learning, the human brain works in constant changing, and what we learn we store in the long-term memory. The digital management of personal learning will play a role of partnership in relation to our memory. The reason is that it will bring concrete elements that will direct resonance what we learn and memorize, along with the digital records and the paths we have traveled to get to the acquisition of knowledge. Through literature review, this text makes the connection, analysis and convergence in three major areas of study. These are: human memory, constructivist learning theory and digital technologies. Related to human memory, its divisions and classifications are analyzed, especially long-term memory, working memory and their central executive subdivisions, phonological loop, visuospatial sketch and episodic retainer. Another aspect addressed is the importance of writing for both memory and for development of ideas and simple or complex reasoning. Authors such as Lent, Baddeley, Pozo, among others, will be assayed. In constructivist learning, the importance of prior learning and anchorage conditions of a new object of knowledge is discussed. Piaget and Ausubel s concepts of assimilation and accommodation, progressive differentiation and integrative reconciliation are analyzed. Another important concept is the delayed and early revisiting in the learning process. In digital technology, the thesis contextualizes the importance of cloud storage, mobile and compact devices, the hologram technology, wearable devices and knowledge recording software. Existing technologies (2015) and those foreseen in a horizon of two decades are discussed. Finally, the study proposes an orchestration of digital technologies, taking into account the analyzes done, and it comes to the conclusion that the technology will bring a new paradigm of how we will make the management of personal learning through digital devices and technologies / Quando se fala em tecnologia digital e internet, pensa-se no acesso a um mundo infinito de informação. Por outro lado, durante a vida, aprendemos uma imensidão de conhecimentos que ficam guardados em nossa memória e espalhados em arquivos, pastas e textos, digitais ou físicos. Essa dissertação propõe-se a olhar para essa imensidão interna de conhecimento e investigar como a tecnologia digital pode ser usada para organizá-la, registrá-la e acessá-la de maneira eficiente e duradora. De forma paralela ao aprendizado, o cérebro humano trabalha em constante transformação, e aquilo que aprendemos guardamos na memória de longa duração. A gestão digital do aprendizado pessoal fará um papel de parceria em relação à nossa memória. Isso porque trará elementos concretos que farão ressonância direta daquilo que aprendemos e memorizamos, com os registros digitais e os caminhos que percorremos para chegar à aquisição de um conhecimento. Através de revisão bibliográfica, este texto faz a conexão, análise e convergência, em três grandes áreas de estudo. São elas: memória do ser humano, teoria de aprendizagem construtivista e as tecnologias digitais. Da memória do ser humano são analisadas as suas divisões e classificações, e em especial a memória de longa duração, a memória de trabalho e suas subdivisões executivo central, alça fonológica, esboço visuoespacial e retentor episódico. Um outro aspecto tratado é a importância da escrita, tanto para a memorização quanto para o desenvolvimento de ideias e raciocínios simples ou complexos. São abordados autores como Lent, Baddeley, Pozo, entre outros. Na aprendizagem construtivista, discute-se a importância do aprendizado anterior e as condições de ancoragem de um novo objeto de conhecimento. São trabalhados os conceitos de assimilação e acomodação de Piaget e de Ausubel, a diferenciação progressiva e a reconciliação integradora. Outro conceito importante são as revisões (revisitações) precoces e adiadas no processo de aprendizagem. Em tecnologia digital, a dissertação contextualiza a relevância do armazenamento em nuvem, dos dispositivos móveis e compactos, da tecnologia de hologramas, de dispositivos vestíveis e dos softwares de registro de conhecimento. São tratadas as tecnologias já existentes (2015) e aquelas previstas em um horizonte de duas décadas. Por fim, o estudo propõe uma orquestração das tecnologias digitais, levando em conta as análises feitas, e chega à conclusão de que as tecnologias trarão um novo paradigma de como faremos a gestão do aprendizado pessoal através dos dispositivos e tecnologias digitais
18

Étude électrophysiologique de la mémoire à court terme auditive

Guimond, Synthia 05 1900 (has links)
La présente étude s’intéresse aux mécanismes neuronaux qui sous-tendent la rétention en mémoire à court terme auditive (MCTA) en utilisant la technique des potentiels reliés aux événements (PRE). Dans l’Expérience 1, nous avons isolé une composante de PRE, nommée SAN pour « sustained anterior negativity ». La SAN augmentait en amplitude négative plus le nombre de sons à maintenir en MCTA augmentait. Cet effet de charge était présent, bien que la durée totale des stimuli restait la même entre les conditions. L’effet de charge observé par la SAN dans l’Expérience 1 disparaissait dans l’Expérience 2, où les mêmes sons étaient utilisés, mais où la mémorisation de ceux-ci n’était plus requise. Finalement, dans l’Expérience 3, la tâche de MCTA a été effectuée avec et sans suppression articulatoire durant l'intervalle de rétention. L’effet de charge trouvé dans l’Expérience 1 était de nouveau observé, lorsque les participants faisaient la tâche de suppression articulatoire ou non. Ces résultats suggèrent que la SAN reflète l'activité nécessaire pour le maintien des objets acoustiques dans un système de MCTA qui serait distinct de la répétition phonologique. / We studied the neuronal mechanisms that implement acoustic short-term memory (ASTM) for pitch using event-related potentials (ERP). Experiment 1 isolated an ERP component, the sustained anterior negativity (SAN), that increased in amplitude with increasing memory load in ASTM using stimuli with equal duration at all memory loads. The SAN load effect found in Experment 1, when pitch had to be remembered to perform the task, was absent in Experiment 2 using the same sounds when memory was not required. In Experiment 3 the memory task was performed without or with concurrent articulatory suppression during the retention interval, to suppress rehearsal via an articulatory loop. Load-related effects found in Experiment 1 were found again, whether participants engaged in concurrent suppression or not. The results suggest that the SAN reflects activity required to maintain pitch objects in an ASTM system that is distinct from articulatory rehearsal.

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