Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

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

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.

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

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.

Visual working memory (WM) is the ability to hold information in mind for a short time before acting on it. The capacity of WM is strikingly limited. To make the most of this precious resource, humans exhibit a high degree of cognitive flexibility: We can prioritize information that is relevant to behavior, and inhibit unnecessary distractions. This thesis examines some behavioral and neural correlates of flexibility in WM. When information is of particular importance, anticipatory attention can be directed to where it will likely appear. Oscillations in visual cortex, in the 10-Hz range, play an important role in regulating excitability of such prioritized locations. Chapter 4 describes how even spontaneous fluctuations in 10-Hz synchronization (measured by electroencephalography, EEG) before encoding influence WM. Chapters 2 and 3 describe how attention can be directed retrospectively to items even if they are already stored in WM. Chapter 3 discusses how retrospective cues change neural synchronization similarly to anticipatory cues. Behavioral and neural measures additionally indicate that the boosting of an item through retrospective cues does not require prolonged deployment of attention: rather, it may be a transient process. The second half of this thesis additionally examines how items are represented in visual WM. Chapter 5 summarizes a study using pattern analysis of magnetoencephalographic (MEG) and EEG data to decode features of visual templates stored in WM. Decoding appears transiently around the time when potential target stimuli are expected, in line with a flexible reactivation mechanism. Chapter 6 further examines separate cortical networks involved in protecting vs. updating items in WM, and tests whether task relevance changes how well WM contents can be decoded. Finally, Chapter 7 summarizes the thesis and discusses how attentional flexibility can merge WM with a wider range of sources of behavioral control.

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

Tabagistas atendem seletivamente a estímulos ambientais relacionados ao cigarro, um processo cognitivo implícito denominado viés na atenção (VA). Contudo, não está claro se o VA persiste em ex-fumantes. Por isso, avaliou-se a influência do tempo de abstinência no VA em 62 ex-fumantes (de 50±11 anos) através de uma tarefa de atenção visual em computador. Independente do tempo de abstinência, os participantes evitaram as pistas associadas ao tabaco. Esta esquiva foi mais pronunciada em tempos de exposição maiores. Os ex-fumantes também atribuíram pouca valência emocional às imagens associadas ao cigarro e reportaram índices baixos de fissura antes e após a tarefa. O VA negativo e a menor valência emocional destas pistas podem constituir um processo de modulação da atenção típico da abstinência prolongada, no qual estratégias cognitivas são empregadas para manter este estado. Os resultados obtidos contribuem para a compreensão da cognição implícita na adição e sua importância no tratamento e prevenção do tabagismo. / Smokers selectively attend to smoking-related cues, an implicit cognitive process called attentional bias (AB). However, it is unclear whether former smokers present AB. Therefore, we evaluated the influence of abstinence time in VA in 62 exsmokers (50 ± 11 years-old) through a visual probe task. Participants avoided smoking cues despite of abstinence time. This avoidance was more pronounced in longer stimuli exposition. Former smokers also attributed little emotional valence to smoking cues and reported low craving rates both before and after the task. The negative AB and low emotional valence of smoking cues might constitute a process of attentional modulation typical of longer abstinence, in which cognitive strategies are employed to maintain this state. The results contribute to the understanding of implicit cognition in addiction and its importance to smoking treatment and prevention.

Doctor of Philosophy / Department of Psychological Sciences / Lester C. Loschky / Visual resolution (i.e., blur or clarity) is a natural aspect of vision. It has been used by film makers to direct their audience’s attention by focusing the depth of field such that the critical region in a scene is uniquely clear and the surrounding is blurred. Resolution contrast can focus attention towards unique clarity, as supported by previous eye tracking and visual search research (Enns & MacDonald, 2013; Kosara, Miksch, Hauser, Schrammel, Giller, & Tscheligi, 2002; & McConkie, 2002; Peterson, 2016; Smith & Tadmor, 2012). However, little is known about how unique blur is involved in guiding attention (e.g., capture, repel, or be ignored). Peterson (2016) provided reaction time (RT) evidence that blur is ignored by selective attention when resolution is not task-relevant. Perhaps visual resolution is a search asymmetry where unique clarity can be used to guide selective attention during search, but unique blur cannot guide attention. Yet, perhaps the RT evidence was not sensitive enough with Peterson’s (2016) methodology to observe unique blur capturing or repelling attention. Eye movements (e.g., letter first fixated) may be more sensitive than RT as it measures blur and clarity’s influence on guiding attention earlier in a trial. The current study conducted three experiments that investigated: a) how visual resolution guides attention when it is task-irrelevant (Exp. 1), b) whether visual resolution is a search asymmetry, by manipulating resolution’s task-relevance (Use Blur, Use Clarity, Do Not Use Unique Blur or Clarity, & No Instructions) (Exp. 2), and c) whether blur and/or clarity are processed preattentively or require attention (Exp. 3). Experiments 1 and 2 manipulated blur and clarity (Exp. 1 Resolution = Task-irrelevant & Exp. 2 Resolution = Task-relevant), during a rotated L and T visual search measuring RT and eye movements. Experiment 1 found with the more sensitive eye movement measures that unique clarity strongly captured attention while unique blur weakly repelled attention towards nearby clarity (or clarity, especially that close to blur, captured attention). Experiment 2 found evidence that visual resolution is not a search asymmetry because the influence of resolution on selective attention was contingent upon its task-relevance, which theoretically supports the presence of a reconfigurable resolution feature detector. Experiment 3 used a feature search for either blur or clarity (i.e., resolution was task-relevant) and compared RT x Set Size search slopes. Both blurred and clear target present RT x Set Size search slopes were ~ 1 msec/item. The results strongly supported that blur and clarity are both processed preattentively, and provided additional evidence that resolution is not a search asymmetry. Overall, the current studies shed light on how visual resolution is processed and guides selective attention. The results revealed that visual resolution is processed preattentively and has a dynamic relationship with selective attention. Predicting how resolution will guide attention requires knowledge of whether resolution is task relevant or irrelevant. By increasing our understanding of how resolution contrast guides attention, we can potentially apply this knowledge to direct viewers’ attention more efficient using computer screens and heads-up displays.

<p>One major focus of anxiety research in recent years has been the identification of cognitive factors that promote increased vulnerability to anxiety. Cognitive formulations propose that anxiety is characterised by an increased tendency to attend to negatively valenced emotional information, and that this bias may play a causal role in the development and maintenance of clinical anxiety. Evidence suggests that this anxiety-linked processing bias occurs even in conditions in which the stimuli are masked in order to prevent awareness of the content (i.e., <i>preattentive bias</i>). The present thesis focused principally on the preferential processing of threat-related information that occurs outside awareness. Two different outcome measures were used to index preferential preattentive processing of threat-related information in non-clinical populations: The emotional Stroop task was used to index <i>selective attention</i> to masked presentation of threatening word stimuli, whereas skin conductance responses were used to index <i>selective autonomic responses</i> to masked presentation of threatening pictorial stimuli. The empirical studies in the present thesis showed that elevated levels of trait anxiety promote preferential preattentive processing of negatively valenced information, whereas elevated levels of social desirability (interpreted as defensiveness) generally prevent preferential preattentive processing of negatively valenced information, especially among those at higher levels of trait anxiety, irrespective of outcome measure used. Moreover, previous research has demonstrated that a person’s most common emotional reaction when encountering a stressful event is causally influenced by that person’s habitual tendency to selectively encode the most threatening aspects of all available information. Thus, preattentive bias (as measured with the emotional Stroop task) was used to predict the emotional responses (as seen on self-reported emotional distress and autonomic reactivity) following exposure to a laboratory stressor. This study showed that preattentive bias to negative information had significant effects on both self-reported and physiological measures in response to a laboratory stressor, but in diametrically opposite directions. Specifically, whereas preattentive bias was positively associated with self-reported negative emotional response, it was negatively associated with a physiological indicator of emotional response. The results were discussed in terms of an inability to automatically inhibit the processing of threatening cues, which seems to be a vulnerability marker for anxiety. Whether this bias is ultimately sufficient for the development of clinical anxiety remains to be examined in future research. Additionally, more information is needed before it can be established that the emotional Stroop task can be viewed as a reliable diagnostic tool for determining an individual’s anxiety status.</p>