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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.
81

Effects of a Dual-Generation Intervention on Supportive Parenting Behaviors and their Relation to Child Brain Function for Selective Attention in Families from Lower Socioeconomic Status Backgrounds

Santillán, Jimena 10 April 2018 (has links)
Parents and Children Making Connections – Highlighting Attention (PCMC-A) is a dual-generation intervention program for families from lower socioeconomic status backgrounds that includes parenting training for parents and attention training for preschool-aged children. PCMC-A has been shown to impact brain function for selective attention in children, the ability to enhance relevant information and suppress competing, distracting information. With the goal of increasing our understanding of how PCMC-A operates to promote gains in child brain function for selective attention, the main objective of this dissertation was to test intervention-related changes in supportive parenting behaviors as an explanatory mechanism for the effect of PCMC-A on neural indices of selective attention. To better understand the profile of those who benefit from PCMC-A to different extents, we also examined moderators of the effect of PCMC-A on supportive parenting and on child brain function for selective attention. These questions were examined as part of the randomized controlled trial to evaluate the impact of PCMC-A on Head Start preschoolers and their parents, employing a multi-method approach. We found that participation in PCMC-A led to increases in specific aspects of supportive parenting behaviors coded from observed parent-child interactions, which were moderated by child and mother characteristics at the pre-assessment, including mother reports of child behavior problems, child age, and maternal interactive language use. We also replicated with a larger sample an effect of PCMC-A on child selective attention measured using the event-related potential technique, which was moderated by mother reports of child social skills at the pre-assessment. Even though we documented changes in both of these outcomes as a function of PCMC-A, we did not find evidence that changes in supportive parenting explained gains in child selective attention, suggesting that other explanatory mechanisms may be at play. Together, the findings of the present dissertation characterize the effect of PCMC-A on supportive parenting behaviors and child selective attention, begin to paint a picture of the families who benefit most and least from this intervention, and contribute to our understanding of the mechanisms through which PCMC-A impacts child brain function for selective attention. This dissertation includes unpublished co-authored material.
82

Études des effets de l’anxiété non pathologique sur l’attention sélective et la mémoire de travail : relation avec la vulnérabilité émotionnelle au stress / Effects of non-clinical anxiety on selective attention and working memory, in relation with emotional stress vulnerability

Tedesco, Adrien 19 January 2015 (has links)
Notre travail s’inscrit dans la problématique du stress au travail et traite des moyens d’évaluation du stress à déployer en matière de prévention. Par des méthodes d’évaluation implicites, nous avons d’abord étudié la prédiction de la vulnérabilité émotionnelle au stress, que nous avons définie comme la tendance individuelle à ressentir des émotions négatives en situation stressante. Nous avons focalisé nos travaux sur les liens entre l’anxiété non pathologique et la mémoire de travail, puis sur la relation entre l’anxiété et l’attention sélective. Nous avons mis en évidence le potentiel de deux tâches cognitives (la tâche de transformation de lettre et la dot-probe task) à prédire la vulnérabilité émotionnelle au stress. Par ailleurs, nous répliquons les résultats d’autres chercheurs démontrant : 1/ l’impact délétère d’un trait d’anxiété élevé sur les performances lors d’une tâche de mémoire de travail complexe réalisée en condition stressante, et 2/ que les individus au trait d’anxiété élevé se distinguent des sujets peu anxieux par des traitements attentionnels de l’information menaçante particuliers. Parallèlement, notre travail a consisté à élaborer et valider un outil informatisé de mesure explicite du stress et des émotions. Par ce dispositif, nous avons tenté de compléter la gamme des outils d’évaluation du stress déployés actuellement dans les entreprises. Notre outil (le QISE) constitue une solution capable d’évaluer le stress et l’anxiété en relation avec une situation ou une activité ciblée, au choix de l’évaluateur. La mesure se veut flexible, rapide à administrer et multidimensionnelle. Le développement de ce dispositif s’inscrit dans un projet plus large sur la Mesure et la Maitrise du Stress en Situation d’Apprentissage Informatisé (projet MASSAI) financé par la 11ème campagne FUI. Les solutions développées ou envisagées dans ce travail constituent des outils numériques pour la prévention du stress au travail. / The present research is part of the general domain of stress at work, and more precisely, deals with the question of preventing stressful situations in this context. First, the focus was made on the prediction, by implicit methods, of emotional vulnerability to stress. This concept has been defined as the individuals’ tendency to experience negative emotions in stressful situations. To this end, we examined the relationships between non-clinical anxiety and working memory capacities, as well as the relationships between anxiety and selective attention. These first analyses highlighted the potential of two cognitive tasks (the letter transformation task and the dot-probe task) to predict emotional vulnerability to stress. In addition, we replicated the results of previous research showing 1 / the negative impact of a high-trait anxiety on performance in a complex working memory task performed under stressful condition, and 2 / that individuals with high anxiety experience difficulties in disengaging their attention from threatening information. Second, the present work also consisted in the development and the validation of an explicit computerized measure of stress and emotions. With this program, we aimed at completing the range of tools currently available and used in the working context to assess stress. Our tool (the QISE) offers a solution to evaluate stress and anxiety in relation to a situation or an activity identified by the evaluator. This program presents several advantages such as its flexibility, its rapidity and its multidimensionality. The development of this program was also part of a larger project called MASSAI funded by the 11th FUI campaign. The set of solutions presented in this project aims at developing computerized tools for the prevention of stress in the working context.
83

É possível uma divisão da atenção visual automática no espaço? / Is it possible to split spatial automatic attention?

Thaís Santos Contenças 23 March 2009 (has links)
Existe controvérsia na literatura sobre a possibilidade de divisão espacial da atenção visual. Alguns autores encontraram evidências de que a atenção visual voluntária se divide no espaço. No entanto, a possibilidade de divisão da atenção automática ainda não foi adequadamente investigada. O objetivo deste trabalho foi investigar a possibilidade de uma divisão da atenção visual automática no espaço. Em um primeiro e segundo experimentos testamos a possibilidade da atenção automática se dividir em um mesmo hemicampo (esquerdo ou direito). Em um terceiro e quarto experimentos investigamos a possibilidade de divisão da atenção automática entre os hemicampos visuais (esquerdo e direito). Em conjunto, os resultados deste trabalho sugerem que a atenção automática pode se dividir entre os hemicampos visuais esquerdo e direito, mas em cada um destes hemicampos forma um foco único longo e estreito. / Several studies demonstrated that voluntary visual attention can be divided. The possibility that this also occurs for automatic visual attention was investigated here. In the first and second experiments of this study the possibility of attention division in the same hemifield was examined. In the third and fouth experiments the possibility of attention division between hemifields was examined. The results suggest that automatic visual attention can not divide in the same hemifield but may divide between hemifields.
84

Avaliação da ansiedade de traço e estado no viés de atenção nos canais visual e auditivo

Melo, Wilson Vieira January 2011 (has links)
Ansiedade e atenção são dois conceitos complexos, que se relacionam diretamente em função de estratégias adaptativas relacionadas à sobrevivência em seres humanos. A presente tese teve como objetivo investigar se as ansiedades de traço e de estado estariam relacionadas ao viés de atenção nos canais visual ou auditivo em uma amostra não clínica. Os capítulos apresentam experimentos com a Visual Probe Detection Task, a Escuta Dicótica e o Stroop Emocional. Todos os experimentos foram realizados em população não clínica e comparou os resultados do cálculo do viés de atenção em grupos definidos pelos escores no inventário de ansiedade de traço e de estado. Foi observada a ausência de relação entre a ansiedade de traço e de estado com o viés de atenção nestes experimentos. A falta de especificidade cognitiva dos estímulos que compõem os três experimentos foi proposta como a causa principal destes resultados. / Anxiety and attention are two complex concepts that relate directly because of adaptive strategies related to survival in humans. This doctoral thesis addressed some aspects related to these two issues. It were discussed some aspects of trait and state anxiety and the study of attentional bias in visual and auditory channels. The chapters present the empirical results of the experiments that used the Visual Probe Detection Task, the Dichotic Listening Task and the Emotional Stroop Task. All experiments were performed in non-clinical population and related the results of the evaluation of attentional bias scores with trait and state anxiety. The results showed no relationship between trait and state anxiety with the attentional bias. It discusses possible reasons for this lack of bias in these samples. Among the possibilities, the lack of cognitive specificity of stimuli that make up the three experiments was proposed as the main reason for it.
85

Modelando a atenção seletiva e a saliência visual através de redes complexas / Modeling the selective attention and visual saliency using complex networks

Gustavo Vrech Rigo 22 July 2010 (has links)
A atenção seletiva é uma característica central do sistema visual humano, uma vez que todo o cérebro é otimizado de modo a perceber as informações ao seu redor da forma mais rápida possível. Porém, em geral os trabalhos nesta área apenas verificam quais são as regiões de maior freqüência da atenção seletiva, dando pouca importância para a sua mecânica. A presente dissertação propõe um modelo que represente a atenção seletiva como uma rede complexa, combinando naturalmente as áreas de redes complexas, cadeias de Markov, análise de imagens, atenção seletiva e saliência visual num modelo biologicamente plausível para simular a atenção seletiva. O modelo propõe que pontos importantes da imagem, pontos salientes, sejam caracterizados como vértices da rede complexa, e que as arestas sejam distribuídas de acordo com a probabilidade da mudança de atenção entre dois vértices. Desta forma, a mecânica da atenção seletiva seria simulada pela mecânica da rede complexa correspondente. Foram estudadas imagens em níveis de cinza, sendo estas correspondentes à cena observada. A probabilidade de mudança entre duas regiões, as arestas da rede, foram definidas através de diversos métodos de composição da saliência visual, e as redes resultantes comparadas com redes complexas provenientes de um experimento protótipo realizado. A partir deste experimento foram propostos refinamentos no modelo original, tornando assim a mecânica do modelo o mais próximo possível da mecânica humana da atenção seletiva. / Selective attention is a central feature of the human visual system, since the entire brain is optimized in order to understand the information around as quickly as possible. In general works in this area only search which regions has a higher frequency of selective attention, with little consideration for their mechanics. This study proposes a model that represents the selective attention as a complex network, combining naturally areas of complex networks, Markov chains, image analysis, selective attention and visual salience in a biologically plausible model to simulate the selective attention. The model proposes that the important points of the image, salient points, are identified as vertices of the complex network, and the edges are distributed according to the probability of shift of attention between two vertices. Thus, the mechanics of selective attention would be simulated by the mechanics of correspondent complex network. We studied images in gray levels, which are corresponding to the scene observed. The probability of switching between two regions, the edges of the network were identified through various methods of visual saliency composition, and the resulting networks compared with complex networks from a prototype experiment performed. From this experiment were proposed refinements to the original model, thereby making the mechanical design as close as possible to the mechanics of human selective attention.
86

Avaliação da ansiedade de traço e estado no viés de atenção nos canais visual e auditivo

Melo, Wilson Vieira January 2011 (has links)
Ansiedade e atenção são dois conceitos complexos, que se relacionam diretamente em função de estratégias adaptativas relacionadas à sobrevivência em seres humanos. A presente tese teve como objetivo investigar se as ansiedades de traço e de estado estariam relacionadas ao viés de atenção nos canais visual ou auditivo em uma amostra não clínica. Os capítulos apresentam experimentos com a Visual Probe Detection Task, a Escuta Dicótica e o Stroop Emocional. Todos os experimentos foram realizados em população não clínica e comparou os resultados do cálculo do viés de atenção em grupos definidos pelos escores no inventário de ansiedade de traço e de estado. Foi observada a ausência de relação entre a ansiedade de traço e de estado com o viés de atenção nestes experimentos. A falta de especificidade cognitiva dos estímulos que compõem os três experimentos foi proposta como a causa principal destes resultados. / Anxiety and attention are two complex concepts that relate directly because of adaptive strategies related to survival in humans. This doctoral thesis addressed some aspects related to these two issues. It were discussed some aspects of trait and state anxiety and the study of attentional bias in visual and auditory channels. The chapters present the empirical results of the experiments that used the Visual Probe Detection Task, the Dichotic Listening Task and the Emotional Stroop Task. All experiments were performed in non-clinical population and related the results of the evaluation of attentional bias scores with trait and state anxiety. The results showed no relationship between trait and state anxiety with the attentional bias. It discusses possible reasons for this lack of bias in these samples. Among the possibilities, the lack of cognitive specificity of stimuli that make up the three experiments was proposed as the main reason for it.
87

Cogito, ergo insomnis : I think, therefore I am sleepless

Norell-Clarke, Annika January 2014 (has links)
Insomnia is a common health complaint that often becomes a persistent problem. The theoretical frameworks for understanding and treating insomnia have mostly been behavioural, yet the importance of cognitive processes has received greater attention over the years. The overall aim of this dissertation was to expand the knowledge on the processes from the Cognitive Model of Insomnia by investigating them in novel contexts. Study I examined the outcomes from cognitive therapy for insomnia on adolescents. Study II explored the relationship between cognitive processes and the association with remission and persistence of insomnia in the general population. Lastly, Study III investigated if cognitive processes mediated between cognitive behavioural therapy for insomnia (CBT-I) and outcomes of insomnia and depressive severity in a sample of people with insomnia comorbid with depressive problems. The findings show that cognitive therapy for insomnia affected sleep for adolescents, thus this is a promising treatment option for this age group. Further, it was found that cognitive processes distinguished between adults with normal sleep and persistent insomnia. For people with insomnia, elevated sleep-related worry at baseline increased the risk of reporting persistent insomnia later on, whereas a lowering of selective attention and monitoring, and safety behaviours over time increased the likelihood of remission from insomnia. This has clinical implications for insomnia assessment and treatment, as well as theoretical implications, and warrants further research. CBT-I was associated with greater reductions in dysfunctional beliefs and sleep-related safety behaviours compared to control treatment. Dysfunctional beliefs mediated between CBT-I and insomnia severity and depressive severity respectively. This supports the importance of negative thought content in both insomnia and depression.
88

Avaliação da atenção seletiva em pacientes com misofonia / Evaluation of selective attention in patients with misophonia

Fúlvia Eduarda da Silva 02 October 2017 (has links)
INTRODUÇÃO: A misofonia é caracterizada pela aversão a sons bem seletivos, que provocam uma forte reação emocional. Foi proposto que a misofonia, assim como o zumbido, esteja associada à hiperconectividade entre os sistemas auditivo e límbico. Indivíduos com zumbido de incômodo significativo podem apresentar comprometimento da atenção seletiva, o que ainda não foi demonstrado no caso da misofonia. OBJETIVO: caracterizar uma amostra de indivíduos com misofonia e compará-la com dois grupos controle, um com zumbido (sem misofonia) e outro assintomático (sem zumbido e sem misofonia). METODOLOGIA: Foram avaliados 40 sujeitos normo-ouvintes, sendo 10 com misofonia (grupo misofonia - GM), 10 com zumbido (sem misofonia) (grupo controle zumbido - GCZ) e 20 sem zumbido e sem misofonia (grupo controle assintomático - GCA). Foi realizada anamnese geral em todos os grupos e anamnese específica apenas para o GM. Nos três grupos, foi aplicado o Teste de Identificação de Sentenças Dicóticas em três situações. Na primeira, foi realizado o exame padrão. Em seguida, foi aplicado incluindo mensagem competitiva, uma com som de mastigação (exame mastigação), e outra com white noise (exame white noise). RESULTADOS: A amostra do GM apontou que os primeiros sintomas da misofonia foram percebidos ainda na infância ou adolescência (média 11,5 anos). O grau de incômodo variou de 6 a 10 na escala visual analógica e, dentre os 10 participantes do GM, nove (90%) responderam que a misofonia atrapalha, sempre ou às vezes, a vida social e profissional. No teste de Identificação de Sentenças Dicóticas, foi observado que no exame mastigação, as médias da porcentagem de acertos diferem entre os grupos GM e GCA (valor-p = 0,027) e entre os grupos GM e GCZ (valor-p = 0,002), sendo menor em ambos os casos no GM. Para os exames padrão e white noise, não há diferença entre as médias da porcentagem de acertos nos três grupos (valores-p >= 0,452). CONCLUSÃO: os participantes do GM apresentaram menor porcentagem de acertos no Teste de Identificação de Sentenças Dicóticas na situação de apresentação de um ruído distraidor (exame mastigação) em relação ao mesmo teste aplicado em situação padrão ou white noise, sugerindo que indivíduos com misofonia podem apresentar alteração da atenção seletiva quando expostos a sons que desencadeiam esta condição / INTRODUCTION: Misophonia is characterized by the aversion to very selective sounds, which evoke a strong emotional reaction. It has been proposed that misophonia, as well as tinnitus, is associated with hyperconnectivity between the auditory and limbic systems. Individuals with bothersome tinnitus may have selective attention impairment, but it has not been demonstrated in case of misophonia yet. OBJECTIVE: to characterize a sample of misophonic subjects and compare it to two control groups, one with tinnitus individuals (without misophonia) and the other one with asymptomatic individuals (without misophonia and without tinnitus), regarding self-perception of the condition and selective attention. METHODOLOGY: we had evaluated 40 normal hearing participants: 10 with misophonia (GM), 10 with tinnitus (without misophonia) (GCZ) and 20 without tinnitus and without misophonia (GCA). General questionnare was applied in all of three groups and specific misophonia questionnaire was applied only in GM. In order to evaluate the selective attention, it was applied the Dichotic Sentence Identification (DSI) Test in three situations: In the first one, it was applied the original test. Then, the test was applied in two other situations including two competitive sounds, one with chewing sound (chewing test), and the other one with white noise sound (white noise test). RESULTS: The GM sample indicated that the onset of misophonia occurred in childhood or adolescence (mean 11.5 years). According to the visual analog scale, the discomfort with misophonia ranged from 5 to 10, and nine (90%) participants answered that misophonia always or sometimes limits their social and professional interactions. In the chewing test, it was observed that the average of correct responses differed between GM and GCA groups (pvalue = 0.027) and between GM and GCZ groups (p-value = 0.002), in both cases it was lower in GM. In the original and white noise tests, no difference was observed between the averages of correct responses in the three groups (p-values >= 0.452). CONCLUSION: The GM participants had a lower percentage of correct responses in the chewing test, suggesting that individuals with misophonia may have selective attention impairment when they are exposed to sounds that trigger the condition
89

Cyclical Variations in Object and Spatial-based Attention

Unknown Date (has links)
Spatial-based attention is shown to vary in strength over short intervals of time. Whether object-based selection also has similar temporal variability is not known. Egly, Driver and Rafal (1994) demonstrated using 2-rectangle displays how both spatial and object-based selection engages in processing of a visual scene. In Experiment-1 using the 2-rectangle paradigm we measured temporal variability of target detection by presenting targets at a variable SOA. In Experiment-2, we used 4-squares to preclude any object-based selection and measured temporal variability in target detection at similar locations as in Experiment-1. We found target detection to be periodic in delta and theta hertz rhythm in both Experiment-1 and Experiment-2 upon comparing corresponding cue-valid and same-object locations. Similar spectral profiles across experiments indicate a split-spotlight of spatial attention that rhythmically monitors cue-valid and other invalid locations. Future experiments are needed to determine whether object-based selection is periodic in nature. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
90

A Masking Procedure for Stimulus Control Assessment

Condon, David 08 1900 (has links)
The present series of experiments were designed to investigate the utility of the use of a masking system to assess the development of stimulus control. The first experiment compares sample observing time with response accuracy in a match-to-sample task. The second experiment more closely examines this relation by subdividing the sample stimulus mask into four quadrants. The third experiment compares sample observing time during training with accuracy during a subsequent testing condition to determine if the observed differentiation between the quadrants was correlated with the development of stimulus control.

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