• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 17
  • Tagged with
  • 17
  • 17
  • 17
  • 17
  • 6
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 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.
1

Algumas contribuições experimentais ao estudo do efeito de priming negativo em tarefas de atenção seletiva. / Some experimental contributions to the study of the negative priming effect in selective attention tasks.

Rosin, Fabiana Monica 07 March 2001 (has links)
Foi estudado o efeito de priming negativo associado à supressão do distrator palavra-cor de Stroop (Estudo 1), à supressão do local (Estudo 2) e à identidade do distrator (Estudos 3 e 4). No Estudo 1 constatou-se que a prática prévia em palavras-cor eliminou o efeito da ordem das condições experimentais sobre o índice de priming negativo. No Estudo 2, o efeito de priming negativo foi observado somente no hemicampo direito. A execução concorrente de uma tarefa verbal eliminou os efeitos de lateralidade, mas o efeito de priming negativo permaneceu significante. Estes achados são discutidos em termos de processamento interhemisférico sob condições que exigiriam maior controle da atenção. Os estudos 3 e 4 apresentam tarefas de comparação de pares de dígitos. A versão de papel e lápis da tarefa de comparação de dígitos permitiu avaliar de maneira simples e rápida o efeito de priming negativo. A versão computadorizada, revelou uma interação entre os componentes espacial e de identidade. Ambos os grupos de adultos jovens e idosos revelaram priming negativo nas tarefas de Stroop e de localização espacial. Nas tarefas de identificação do alvo somente os adultos jovens mostraram efeito de priming negativo. Os presentes achados são consistentes com a proposta de mecanismos inibitórios diferenciados na supressão da identidade e de localização espacial. / The development of sensitive and simple tests for the assessment of the negative priming effect has theoretical relevance to the elucidation of selective attention models, and also practical and potential clinical implications. The negative priming effect has been regarded as an index of inhibitory attentional processing and was proposed for the detection of syndromes that involve cognitive impairment. Diminished negative priming was reported in studies of individual differences, developmental stage, and clinical populations. However, evidences suggest that tasks requiring responses to the color feature, location or object identity of the stimuli may comprise distinct types of negative priming tasks. The following studies presents data for computerized and paper-and-pencil tasks to examine negative priming for Stroop color-word, location and identity distractors. All four studies take into account aging effects across the tasks. For comparisons between age-groups, proportional performance scores (ratio) were used. A first study employed a reading-sheet Stroop-color-word task, in which the participant is asked to name the colors of the ink in which words with incongruent color names have been printed. Color-word interference is indicated by increased time to complete the conflicting color-word condition compared with a nonconflicting condition with patches of color or strings of Xs. The greater strength of the interference, when the target ink-color of the present stimulus is the distracting color name of the previous stimulus, is attributed to the negative priming effect. A pilot experiment showed that the order of the list conditions containing unrelated and related stimuli affected the negative priming index. The analysis of data demonstrated that a practice trial in color naming of conflicting color-words before the color-word conditions eliminated the effect of the order of the lists. In addition, there was a reliable Stroop reverse interference after practice in color naming, as indicated by the fact that the incongruent color-ink affected post-test word-reading, whereas it had no effect in the pretest word-reading. With practice procedure, older and younger subjects did not differ in their proportional interference scores, whereas the negative priming and reverse effects were increased for older adults. Study 2 examined the negative-priming effect in a spatial localization task under single- and dual-task conditions. The task required the subject to detect the location of a target letter, ‘O’, while ignoring a distractor letter, ‘X’, when it was present. Significant negative-priming effects were observed under both task conditions, with increased response times for trials in which target location had matched the location of the distractor on the preceding. The magnitude of the negative priming effect was not different for older and younger adults. The performance in the single-task condition showed laterality effects with a right visual field advantage for control and target-alone trials, but not for related trials. In consequence, in the single-task condition, negative priming was observed only for targets displayed in the right hemifield. However, a concurrent digit span task, with a load level that had shown no affect on the dual-task coordination capacity, eliminated the laterality effects, but the negative priming effect remained. These results are considered as neuropsychological evidence that interhemispheric processes may operate under more controlled conditions. Studies 3 and 4 examined negative priming by using an identity-based task that required participants to select the greater of two-digits display or the digit that was paired with an asterisk. Study 3 presents data for a computerized version of the task. Negative-priming was expressed as a slowing in the time to name the digit that had been ignored in the preceding trial, compared to control trials with consecutive targets and distractors always different. Analysis of data revealed that negative priming was reliable only for younger adults, and only when target probe and distractor prime appeared at the same location, suggesting that suppression for location of distractor was underpinning the negative priming effect. However, response latencies for the control trials were facilitated when the target probe and the distractor prime shared the same location. Thus, local suppression affected negative priming for attended distractors with a cost in the response latency for ignored-repetition trials and with a gain in response latency for control trials when the locus of target-probe and distractor-prime was the same. In contrast, older adults’ performance showed local suppression for both ignored-repetition and control trials. This may explain the lack of negative priming for older adults in the digit-comparison task. Study 4 presents data for a new paper-and-pencil version of the digit-comparison task to obtain a practical measure of negative priming that do not require cumbersome technical equipment. In that task, subjects were asked to circle digits that were paired with asterisks and the greater of two digits in a series of digit pairs listed on a sheet of paper. For younger participants, but not for older participants, the time to complete the sheet with related pairs was slower than for unrelated pairs. In addition, the reduced scores of negative priming in older adults were associated with the lowest sustained attention scores from Toulouse-Piéron test. These results suggest that older adults’ performance in the digit-comparison task were mainly related to flexibility and sustained attentional scores, and the lower sustained attentional coefficient seemed to be the best predictor of diminished or reversed negative priming in older adults. Younger adults showed reliable negative priming across all tasks. In contrast, older adults showed negative priming in Stroop and spatial tasks, when compared with younger subjects performance, but reduced negative priming in identity suppression tasks. The findings are consistent with neurophysiological and behavioural evidence that identity and location suppressing may rely on separate inhibitory mechanisms, and that not all of these processes are weakened by factors associated with age.
2

Algumas contribuições experimentais ao estudo do efeito de priming negativo em tarefas de atenção seletiva. / Some experimental contributions to the study of the negative priming effect in selective attention tasks.

Fabiana Monica Rosin 07 March 2001 (has links)
Foi estudado o efeito de priming negativo associado à supressão do distrator palavra-cor de Stroop (Estudo 1), à supressão do local (Estudo 2) e à identidade do distrator (Estudos 3 e 4). No Estudo 1 constatou-se que a prática prévia em palavras-cor eliminou o efeito da ordem das condições experimentais sobre o índice de priming negativo. No Estudo 2, o efeito de priming negativo foi observado somente no hemicampo direito. A execução concorrente de uma tarefa verbal eliminou os efeitos de lateralidade, mas o efeito de priming negativo permaneceu significante. Estes achados são discutidos em termos de processamento interhemisférico sob condições que exigiriam maior controle da atenção. Os estudos 3 e 4 apresentam tarefas de comparação de pares de dígitos. A versão de papel e lápis da tarefa de comparação de dígitos permitiu avaliar de maneira simples e rápida o efeito de priming negativo. A versão computadorizada, revelou uma interação entre os componentes espacial e de identidade. Ambos os grupos de adultos jovens e idosos revelaram priming negativo nas tarefas de Stroop e de localização espacial. Nas tarefas de identificação do alvo somente os adultos jovens mostraram efeito de priming negativo. Os presentes achados são consistentes com a proposta de mecanismos inibitórios diferenciados na supressão da identidade e de localização espacial. / The development of sensitive and simple tests for the assessment of the negative priming effect has theoretical relevance to the elucidation of selective attention models, and also practical and potential clinical implications. The negative priming effect has been regarded as an index of inhibitory attentional processing and was proposed for the detection of syndromes that involve cognitive impairment. Diminished negative priming was reported in studies of individual differences, developmental stage, and clinical populations. However, evidences suggest that tasks requiring responses to the color feature, location or object identity of the stimuli may comprise distinct types of negative priming tasks. The following studies presents data for computerized and paper-and-pencil tasks to examine negative priming for Stroop color-word, location and identity distractors. All four studies take into account aging effects across the tasks. For comparisons between age-groups, proportional performance scores (ratio) were used. A first study employed a reading-sheet Stroop-color-word task, in which the participant is asked to name the colors of the ink in which words with incongruent color names have been printed. Color-word interference is indicated by increased time to complete the conflicting color-word condition compared with a nonconflicting condition with patches of color or strings of Xs. The greater strength of the interference, when the target ink-color of the present stimulus is the distracting color name of the previous stimulus, is attributed to the negative priming effect. A pilot experiment showed that the order of the list conditions containing unrelated and related stimuli affected the negative priming index. The analysis of data demonstrated that a practice trial in color naming of conflicting color-words before the color-word conditions eliminated the effect of the order of the lists. In addition, there was a reliable Stroop reverse interference after practice in color naming, as indicated by the fact that the incongruent color-ink affected post-test word-reading, whereas it had no effect in the pretest word-reading. With practice procedure, older and younger subjects did not differ in their proportional interference scores, whereas the negative priming and reverse effects were increased for older adults. Study 2 examined the negative-priming effect in a spatial localization task under single- and dual-task conditions. The task required the subject to detect the location of a target letter, ‘O’, while ignoring a distractor letter, ‘X’, when it was present. Significant negative-priming effects were observed under both task conditions, with increased response times for trials in which target location had matched the location of the distractor on the preceding. The magnitude of the negative priming effect was not different for older and younger adults. The performance in the single-task condition showed laterality effects with a right visual field advantage for control and target-alone trials, but not for related trials. In consequence, in the single-task condition, negative priming was observed only for targets displayed in the right hemifield. However, a concurrent digit span task, with a load level that had shown no affect on the dual-task coordination capacity, eliminated the laterality effects, but the negative priming effect remained. These results are considered as neuropsychological evidence that interhemispheric processes may operate under more controlled conditions. Studies 3 and 4 examined negative priming by using an identity-based task that required participants to select the greater of two-digits display or the digit that was paired with an asterisk. Study 3 presents data for a computerized version of the task. Negative-priming was expressed as a slowing in the time to name the digit that had been ignored in the preceding trial, compared to control trials with consecutive targets and distractors always different. Analysis of data revealed that negative priming was reliable only for younger adults, and only when target probe and distractor prime appeared at the same location, suggesting that suppression for location of distractor was underpinning the negative priming effect. However, response latencies for the control trials were facilitated when the target probe and the distractor prime shared the same location. Thus, local suppression affected negative priming for attended distractors with a cost in the response latency for ignored-repetition trials and with a gain in response latency for control trials when the locus of target-probe and distractor-prime was the same. In contrast, older adults’ performance showed local suppression for both ignored-repetition and control trials. This may explain the lack of negative priming for older adults in the digit-comparison task. Study 4 presents data for a new paper-and-pencil version of the digit-comparison task to obtain a practical measure of negative priming that do not require cumbersome technical equipment. In that task, subjects were asked to circle digits that were paired with asterisks and the greater of two digits in a series of digit pairs listed on a sheet of paper. For younger participants, but not for older participants, the time to complete the sheet with related pairs was slower than for unrelated pairs. In addition, the reduced scores of negative priming in older adults were associated with the lowest sustained attention scores from Toulouse-Piéron test. These results suggest that older adults’ performance in the digit-comparison task were mainly related to flexibility and sustained attentional scores, and the lower sustained attentional coefficient seemed to be the best predictor of diminished or reversed negative priming in older adults. Younger adults showed reliable negative priming across all tasks. In contrast, older adults showed negative priming in Stroop and spatial tasks, when compared with younger subjects performance, but reduced negative priming in identity suppression tasks. The findings are consistent with neurophysiological and behavioural evidence that identity and location suppressing may rely on separate inhibitory mechanisms, and that not all of these processes are weakened by factors associated with age.
3

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

Silva, Fúlvia Eduarda da 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
4

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

Rigo, Gustavo Vrech 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.
5

Efeito da autofala na aprendizagem motora / Effect of self-talk on motor learning

Ferreira, Thiago Rogel Santos 09 December 2013 (has links)
O objetivo deste estudo foi investigar os efeitos da autofala na aprendizagem motora. A tarefa utilizada foi o forehand do tênis de campo. Oitenta e quatro universitários foram divididos em cinco grupos experimentais e um controle (n = 14). Dentre os grupos experimentais um deles utilizou-se de quatro dicas para direcionamento da atenção a elementos-chave da rebatida, os demais fizeram uso de apenas uma das quatro dicas (bola, quique, bater, pronto), já o grupo controle recebeu somente instruções gerais fornecidas a todos os participantes. Na fase de aquisição todos os grupos realizaram 180 rebatidas divididas em 60 por dia. Em seguida, eles realizaram um teste de transferência contendo 10 rebatidas com mudança da direção do outro alvo e, após 5 dias, um teste de retenção contendo 10 rebatidas nas mesmas condições da fase de aquisição. A variável dependente foi o acerto ao alvo localizado na quadra adversária. Os resultados mostraram que todos os grupos melhoraram os desempenhos na fase de aquisição, os quais foram mantidos nos testes de transferência e retenção. Entretanto, não foram encontradas diferenças entre os grupos. Concluiu-se que as aprendizagens do forehand com e sem a autofala apresentaram efeitos similares. E, ainda, que a autofala sobre quatro aspectos da tarefa foi similar àquelas com autofala de apenas um aspecto / The aim of this study was to investigate the effects of self-talk on the motor learning. The task was the forehand of the tennis. Eighty-four students were divided into five experimental groups and one control group (n = 14). One of the experimental groups used four cues for directing attention to key elements of forehand. The other groups have made use of only one of the four cues (ball, bounce, hit, ready), and the control group received only general instructions. In the acquisition phase all groups performed 180 trials which were divided into 60 per day. Then they performed a transfer test of 10 trials involving a shift in the target direction and, after 5 days a retention test was run with ten trials in the same conditions of the acquisition phase. The dependent variable was the hit to the target located in the opponent\'s court. The results showed that all groups improved their performances in the acquisition phase, which were kept in the retention and transfer tests. However, no differences were found between groups. It was concluded that the learning of the forehand with and without self-talk showed similar effects. And, that self-talk of four aspects of the task was similar to those with self-talk of only one aspect
6

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

Contenças, Thaís Santos 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.
7

Efeito da autofala na aprendizagem motora / Effect of self-talk on motor learning

Thiago Rogel Santos Ferreira 09 December 2013 (has links)
O objetivo deste estudo foi investigar os efeitos da autofala na aprendizagem motora. A tarefa utilizada foi o forehand do tênis de campo. Oitenta e quatro universitários foram divididos em cinco grupos experimentais e um controle (n = 14). Dentre os grupos experimentais um deles utilizou-se de quatro dicas para direcionamento da atenção a elementos-chave da rebatida, os demais fizeram uso de apenas uma das quatro dicas (bola, quique, bater, pronto), já o grupo controle recebeu somente instruções gerais fornecidas a todos os participantes. Na fase de aquisição todos os grupos realizaram 180 rebatidas divididas em 60 por dia. Em seguida, eles realizaram um teste de transferência contendo 10 rebatidas com mudança da direção do outro alvo e, após 5 dias, um teste de retenção contendo 10 rebatidas nas mesmas condições da fase de aquisição. A variável dependente foi o acerto ao alvo localizado na quadra adversária. Os resultados mostraram que todos os grupos melhoraram os desempenhos na fase de aquisição, os quais foram mantidos nos testes de transferência e retenção. Entretanto, não foram encontradas diferenças entre os grupos. Concluiu-se que as aprendizagens do forehand com e sem a autofala apresentaram efeitos similares. E, ainda, que a autofala sobre quatro aspectos da tarefa foi similar àquelas com autofala de apenas um aspecto / The aim of this study was to investigate the effects of self-talk on the motor learning. The task was the forehand of the tennis. Eighty-four students were divided into five experimental groups and one control group (n = 14). One of the experimental groups used four cues for directing attention to key elements of forehand. The other groups have made use of only one of the four cues (ball, bounce, hit, ready), and the control group received only general instructions. In the acquisition phase all groups performed 180 trials which were divided into 60 per day. Then they performed a transfer test of 10 trials involving a shift in the target direction and, after 5 days a retention test was run with ten trials in the same conditions of the acquisition phase. The dependent variable was the hit to the target located in the opponent\'s court. The results showed that all groups improved their performances in the acquisition phase, which were kept in the retention and transfer tests. However, no differences were found between groups. It was concluded that the learning of the forehand with and without self-talk showed similar effects. And, that self-talk of four aspects of the task was similar to those with self-talk of only one aspect
8

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.
9

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.
10

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.

Page generated in 0.0898 seconds