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This thesis investigated hypnotic reading disruptions to identify parameters of hypnosis that may influence reading and to inform the broader issue of whether hypnotic suggestions impact phenomenal experience versus perceptual-cognitive processing. Chapter 1 reviews the relevant literature and identifies core issues addressed by this program. Chapter 2 presents two experiments and two case studies, which focused on establishing a paradigm for investigating hypnotic reading disruptions; in particular, modulation of the Stroop effect. Findings indicated that disruptions of reading experience and/or reading processing may be influenced by the complexity of the suggestion and the natural response strategies of individuals. Chapter 3 presents two experiments that examined the influence of test time and test demands, and explored the experiential factors underlying response to different suggestions. Findings indicated that both hypnotic and posthypnotic suggestions produced disruptions of reading experience but not reading processing. Also, individuals?? experiences and cognitive strategies varied depending on the suggestion they received. Chapter 4 presents two experiments that compared the impact of three suggestions on reading experience and reading processing. Findings indicated that highs were more likely to achieve disruptions of reading experience in response to a suggestion compatible with their natural strategies. Notably, some highs altered their reading processing and hypnotically modulated Stroop interference. Other highs and lows modified their reading processing, but independent of hypnosis, hypnotisability and a suggestion. Chapter 5 presents one experiment that examined the time course of hypnotic reading disruptions and the influence of test context. Findings indicated that highs could maintain disruptions of reading experience over time. They also modified their reading processing independent of hypnosis and a suggestion. Chapter 6 presents one experiment that examined implicit perception, and the impact of hypnosis and hypnotisability. Findings indicated that highs were influenced by information from reading processing despite their experiences of disrupted reading. Chapter 7 interprets the findings of this program within a proposed model of hypnotic disruptions of reading and Stroop performance. This model differentiates between the mechanisms that may underlie reading experiences, the mechanisms that may underlie reading processing and their interaction, and highlights the value of hypnotic models of cognitive processes.

It is well established that people experience a decline in cognitive functions, such as selective attention (SA), as they get older. SA is the ability to focus on task-relevant information and suppress task-irrelevant information. The Stroop task has been used to assess SA. In the current study, the neural correlates of SA were investigated using functional MRI-Stroop task with cognitively normal older adults (NC), patients with amnestic Mild Cognitive Impairment (aMCI) and patients with mild Alzheimer’s disease (AD). The current study reanalyzed previous master student’s data, due to the disagreement in analyzing the data. In the fMRI data analysis, the contrast of correct responses in the naming incongruent color (SC) condition minus correct responses in the reading incongruent word (RW) condition (SC-RW) in series 2a and 2b was reanalyzed using an event-related analysis. The current Stroop experiment was in a block design with four series: series 0, series 1, series 2a and 2b. In behavioral analysis, the performance of the word-reading task was expected to be significantly better than the color-naming task in series 1, series 2a and 2b because the belief that reading incongruent color word was always an easier task than the color-naming task. The results from behavioral analysis showed that significant more errors were made in reading incongruent color words in series 2a and 2b than in series 1. In the functional MRI data analysis, although brain activation associated with inhibition was expected in the contrast of SC-RW of series 2a & 2b, the results did not show any brain activation. The unexpected results could be due to the RSE that was elicited by the task switching paradigm of series 2a and 2b. The results suggest that the current Stroop task adapted from the Stroop Neuropsychological Screening Test may not yield a Stroop interference effect of sufficient magnitude to be detected with fMRI in the contrast of SC-RW of series 2a and 2b. / Thesis (Master, Neuroscience Studies) -- Queen's University, 2010-09-24 11:33:28.83

This thesis investigated hypnotic reading disruptions to identify parameters of hypnosis that may influence reading and to inform the broader issue of whether hypnotic suggestions impact phenomenal experience versus perceptual-cognitive processing. Chapter 1 reviews the relevant literature and identifies core issues addressed by this program. Chapter 2 presents two experiments and two case studies, which focused on establishing a paradigm for investigating hypnotic reading disruptions; in particular, modulation of the Stroop effect. Findings indicated that disruptions of reading experience and/or reading processing may be influenced by the complexity of the suggestion and the natural response strategies of individuals. Chapter 3 presents two experiments that examined the influence of test time and test demands, and explored the experiential factors underlying response to different suggestions. Findings indicated that both hypnotic and posthypnotic suggestions produced disruptions of reading experience but not reading processing. Also, individuals?? experiences and cognitive strategies varied depending on the suggestion they received. Chapter 4 presents two experiments that compared the impact of three suggestions on reading experience and reading processing. Findings indicated that highs were more likely to achieve disruptions of reading experience in response to a suggestion compatible with their natural strategies. Notably, some highs altered their reading processing and hypnotically modulated Stroop interference. Other highs and lows modified their reading processing, but independent of hypnosis, hypnotisability and a suggestion. Chapter 5 presents one experiment that examined the time course of hypnotic reading disruptions and the influence of test context. Findings indicated that highs could maintain disruptions of reading experience over time. They also modified their reading processing independent of hypnosis and a suggestion. Chapter 6 presents one experiment that examined implicit perception, and the impact of hypnosis and hypnotisability. Findings indicated that highs were influenced by information from reading processing despite their experiences of disrupted reading. Chapter 7 interprets the findings of this program within a proposed model of hypnotic disruptions of reading and Stroop performance. This model differentiates between the mechanisms that may underlie reading experiences, the mechanisms that may underlie reading processing and their interaction, and highlights the value of hypnotic models of cognitive processes.

Delusions are symptomatic of a number of psychiatric disorders; however, nonpsychiatric adults have also been shown to vary on a propensity toward delusional thought, or "delusion-proneness." The current study examined whether there is a relationship between an individual's degree of delusion proneness (on a continuum) and performance on the Stroop task, a cognitive task thought to measure conflict response monitoring. It was theorized that reduced conflict response monitoring ability may relate to (and perhaps cause) increased delusional propensity. A total of 35 nonpsychiatric college students completed a measure of delusion-proneness (Peter's et al. Delusion Inventory-21 item version; PDI-21), and a computerized version of the Stroop task with three conditions- congruent, incongruent, and neutral. It was hypothesized that PDI-21 scores would be positively correlated to Stroop interference contrast scores. Results revealed that delusion-proneness showed a statistically significant positive correlation with the Stroop reaction time contrast score, but not the accuracy constrast score, in the incongruent/congruent contrasts. Our pattern of results suggests that efficiency (i.e. reaction time) of Stroop performance is more sensitive to delusion-proneness, compared to the more gross measure of accuracy. This study appears to be the first to report this relationship across a continuum of delusion-proneness in a nonpsychiatric sample, and overall, the findings suggest that delusion-proneness is related to performance on a behavioral measure of conflict response monitoring and inhibitory control. This research may have implications on treatment interventions used with patients presenting with clinical delusions.

La tâche Stroop est une tâche très utilisée en psychologie car elle permet entre autres l'étude des processus dit automatiques. Cependant, récemment l'utilisation d'une présentation bicolore dans cette tâche, associée aux études liées à une tâche de détection de lettre dans une tâche d'amorçage, suggère que l'accès à la sémantique ne serait pas automatique. Ce qui impliquerait une interprétation différente de la tâche Stroop. Nous avons testé l'hypothèse qu'en présentation bicolore, la diminution observée de l'effet Stroop ne serait pas dû à un blocage de la sémantique mais à une augmentation des capacités d'inhibition. Nous avons pour cela utilisé une condition "associée" qui consistait à présenter des mots associés à une couleur (par exemple "ciel" associé à bleu) afin d'étudier plus spécifiquement l'accès à la sémantique. Dans nos deux premières études reproduisant le protocole des précédentes avec un nombre de participants plus important, nous n'observons pas de diminution de l'effet Stroop associé. Nous avons ensuite utilisé les potentiels évoqués pour montrer la présence de la N400 en condition bicolore pour les mots de couleurs et associés à une couleur dans la tâche Stroop. Pour finir, après avoir testé la présence du biais attentionnel chez des patients alcoolo-dépendants avec une version française du "Alcohol Stroop Test", nous avons montré que des ressources attentionnelles étaient nécessaires pour observer une diminution de l'effet Stroop en présentation bicolore. L'ensemble de nos résultats suggère que la diminution de l'effet Stroop en présentation bicolore nécessite des ressources attentionnelles et que donc l'accès à la sémantique serait un processus automatique, mieux inhibé dans la présentation bicolore. La tâche Stroop utilisée en clinique refléterait donc bien un processus d'inhibition de processus automatiques. / The Stroop task is a well-used task in psychology, in particular because it allows the study of automatic process. Recently the use of a single letter coloring presentation in this task, associated with the studies related to a task of detection of letter, suggests that the access to semantics would not be automatic. This implies a different interpretation from the Stroop task. We tested the assumption that in single letter colored presentation, the reduction observed in the Stroop Effect would not be due to a blocking of semantics but to an increase on the capacities of inhibition. For that we used an "associated" condition where we presented words associated with a color (for example sky associated with blue) to more specifically study the access to semantics. In our two first studies reproducing the preceding protocol with a more important number of participants, we do not observe reduction in the associated stroop effect. Then we used the Potentials Evoked to show the presence of N400 in the single letter colored condition for color words and associated-words. To finish, after having tested the presence of an attentional bias among patients alcohol-dependent with a French version on Alcohol Stroop Test, we showed that attentional resources were necessary to observe a reduction in the Stroop Effect in single letter colored presentation. The whole of our results suggest that the reduction in the Stroop Effect in single letter colored presentation requires attentional resources. The semantic access would be an automatic process. The sense of the word could be inhibiting after activation in single letter colored presentation. The Stroop task used in clinical would thus reflect an inhibition capacity of automatic process.

To explore the application of a cognitive test useful in screening of Exhaustion Disorder (ED), this study aimed to develop a Modified Stroop Task for ED. Participants’ scores on measures of burnout, anxiety, depression and stress were compared with performance on the task. The sample consisted of 56 participants (M=25.3 years), 30 women and 22 males, with the majority enrolled in fulltime higher education. The task consisted of five blocks with 100 stimuli in each block. The task was administered on a computer; upon completion of the task participants completed questionnaires measuring levels of burnout, anxiety and depression, as well as perceived stress. Raw scores on the task were calculated using a format comprised of both response times and number of errors. Data were analysed by comparing mean scores on the Stroop blocks using one-way repeated measures ANOVA. Additionally, median splits were undertaken on the scores on the questionnaires to enable between group comparisons using MANOVAs. The results showed no significant differences between high and low scores on the questionnaires and performance on the task. A Stroop interference effect was observed and there was a tendency that high exhausted participants performed worse than less exhausted participants. In conclusion the Modified Stroop Task offers some promise, although as of yet it cannot be assumed to be an accurate modification of an Emotional Stroop Task, due to limitations regarding the method; preliminary findings may serve as a pilot test for future research.

Although the effect of working memory (WM) load on the magnitude of distractor interference has been studied extensively, a common characteristic in prior research is that the target and distractors belong to different objects. The present experiments investigate the effect of WM load on distractor interference when the relevant and irrelevant information is part of the same object. In two experiments, participants saw stimulus displays that consisted of a memory set followed by a Stroop color stimulus. The tasks were to respond to the color of the stimulus first and then to a memory probe. The principal manipulations were the relationship between the color and meaning of the Stroop stimulus (neutral vs. incongruent) and the level of WM load (high vs. low). The results show that WM load had little effect on the magnitude of Stroop interference. These results were consistent with previous research which shows that WM load plays a limited role in the efficiency of selective attention when the extent of attentional focus was held constant across different WM load conditions. They also emphasize the importance of stimulus structure in understanding selective attention in general, and distractor processing in particular.

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A research method for investigating delusional beliefs is outlined by adopting the delusional belief that one is dead (the Cotard delusion) as a model delusion. Detailed analyses of published case reports of the Cotard delusion demonstrate that the term 'syndrome' as it is currently applied to the belief that one is dead is not helpful in terms of our understanding of the delusion. Four new case studies of the Cotard delusion suggest that preoccupation with belief may play a role in the formation and maintenance of delusions. Preoccupation with delusional belief was investigated using a variant of the 'emotional' Stroop paradigm, commonly used in investigating anxiety disorders. Three individuals with the Cotard delusion, and diagnosed as suffering from depression, showed attentional biases toward words related to the theme of death. Two of the individuals had no history of anxiety and showed no bias toward words related to generalised anxiety. It was therefore suggested that the locus of attentional biases in delusions may be preoccupation with delusional belief, rather than anxiety per se. Consistent with this, a patient with fixed grandiose delusional beliefs, diagnosed with schizophrenia, and not suffering from anxiety, showed attentional bias toward words related to his delusional beliefs. Attentional bias failed to be demonstrated in a group of people with delusions arising in the context of schizophrenia, and reasons for this are discussed. Finally, three groups of individuals, who were free form any form of psychopathology, each showed a trend towards longer colour-naming times towards words related to their respective interests, but none of these were significant. It is concluded that attentional biases in delusions serve to reinforce delusional beliefs by constantly focusing die individual's attention onto delusion- relevant material. Implications for further research are discussed.