Tesi: "Sensory cognition"

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AGGIUS-VELLA, ELENA. "From sensory perception to spatial cognition". Doctoral thesis, Università degli studi di Genova, 2019. http://hdl.handle.net/11567/940911.

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To interact with the environmet, it is crucial to have a clear space representation. Several findings have shown that the space around our body is split in several portions, which are differentially coded by the brain. Evidences of such subdivision have been reported by studies on people affected by neglect, on space near (peripersonal) and far (extrapersonal) to the body position and considering space around specific different portion of the body. Moreover, recent studies showed that sensory modalities are at the base of important cognitive skills. However, it is still unclear if each sensory modality has a different role in the development of cognitive skills in the several portions of space around the body. Recent works showed that the visual modality is crucial for the development of spatial representation. This idea is supported by studies on blind individuals showing that visual information is fundamental for the development of auditory spatial representation. For example, blind individuals are not able to perform the spatial bisection task, a task that requires to build an auditory spatial metric, a skill that sighted children acquire around 6 years of age. Based these prior researches, we hypothesize that if different sensory modalities have a role on the devlopment of different cognitive skills, then we should be able to find a clear correlation between availability of the sensory modality and the cognitive skill associated. In particular we hypothesize that the visual information is crucial for the development of auditory space represnetation; if this is true, we should find different spatial skill between front and back spaces. In this thesis, I provide evidences that spaces around our body are differently influenced by sensory modalities. Our results suggest that visual input have a pivotal role in the development of auditory spatial representation and that this applies only to the frontal space. Indeed sighted people are less accurated in spatial task only in space where vision is not present (i.e. the back), while blind people show no differences between front and back spaces. On the other hand, people tend to report sounds in the back space, suggesting that the role of hearing in allertness could be more important in the back than frontal spaces. Finally, we show that natural training, stressing the integration of audio motor stimuli, can restore spatial cognition, opening new possibility for rehabilitation programs. Spatial cognition is a well studied topic. However, we think our findings fill the gap regarding how the different availibility of sensory information, across spaces, causes the development of different cognitive skills in these spaces. This work is the starting point to understand the strategies that the brain adopts to maximize its resources by processing, in the more efficient way, as much information as possible.

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Kareklas, Kyriacos. "Cognition, individual behaviour and sensory systems in fish". Thesis, Queen's University Belfast, 2017. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.727411.

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This work explores the role of animal personality differences in the interaction between sensing, behaviour and cognition. Typically, animal personality is characterised by patterns of consistency in levels of individual behaviour. In a study of the weakly-electric fish Gnathonemus petersii, otherwise consistent boldness levels are revealed as changeable when fish are in safer conditions. Interestingly, the changes were greater for timid than bold personalities, which implicates individual behavioural-plasticity levels in the expression of personality. Further investigations of the spatial learning of G. petersii confirm that bolder fish decide faster and are also more accurate in choosing a rewarded place, which enables faster learning. The behavioural and cognitive differences between personalities can be linked to neurosensory mechanisms. This was illustrated by investigating asymmetries in sensory input to the brain of G. petersii. Consistent with their behavioural tendency, shier animals were strongly asymmetric towards the left hemisphere, which controls response. Conversely, bolder animals were more strongly asymmetric towards the right hemisphere, which promotes rapid response. In order to identify the extent to which these personality-based individual differences influence social behaviour, the work further regards how the differences between individuals affect the collective functions of groups. The collective behaviour and learning performance of zebrafish Danio rerio did not reflect intra-group personality levels. However, group behaviour was similar to the average of individual behaviour and groups with greater intra-group variance in boldness took longer to reach collective decisions by dispersing. Overall, the work highlights the diverse influence of individual variation and illustrates the usefulness of integrative research in examining this. The findings have important implications for the ecology of wild fish populations, the neurocognitive mechanisms of behaviour and the effect of personality on the survival strategies of vertebrates.

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May, Kristina A. "Nursing utilization of sensory stimuli on the impact of infant cognition". Honors in the Major Thesis, University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1294.

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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.
Bachelors
Nursing
Nursing

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Martorell, Anthony J. Ph D. (Anthony James) Massachusetts Institute of Technology. "Multi-sensory gamma stimulation ameliorates Alzheimer's-associated pathology and improves cognition". Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/132749.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Brain and Cognitive Sciences, June, 2019
Cataloged from the PDF version of thesis. Page 123 blank.
Includes bibliographical references (pages 115-122).
Changes in gamma activity (30-90 Hz) have been observed in humans and animal-models of Alzheimer's disease (AD). Examining the relationship between gamma oscillations and disease pathology is a significant problem in neuroscience. Recent work using a non-invasive light flicker at 40 Hz, termed Gamma ENtrainment Using Sensory stimulus, or 'GENUS', was shown to impact pathology in the visual cortex of AD-mouse models. However, it is not known whether other sensory modalities at 40 Hz can change pathology in higher order brain regions, or affect cognition, in AD-like animal models. In this thesis, I combine in vivo electrophysiology, biochemical and imaging techniques, and behavioral assays to understand the effects of multi-sensory gamma stimulation in AD-like animals. I first show that auditory tone stimulation at 40 Hz (auditory GENUS) can drive gamma frequency neural activity in auditory cortex (AC) and hippocampal CA1. I then demonstrate that seven days of auditory GENUS results in improved spatial and recognition memory and reduced amyloid load in AC and hippocampus of 5XFAD mice. These changes in activation responses were evident in microglia, astrocytes, and vasculature. Additionally, auditory GENUS reduced phosphorylated tau in the tau P301S model. Finally, I demonstrate that combined auditory and visual GENUS, but not either alone, decreases amyloid and produces a microglial-clustering response in the medial prefrontal cortex. Whole brain analysis using SHIELD processing revealed widespread reduction of amyloid plaques throughout neocortex after multi-sensory GENUS. These findings suggest that GENUS can be achieved through multiple sensory modalities with wide-ranging effects across multiple brain areas to improve cognitive function.
by Anthony J. Martorell.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Brain and Cognitive Sciences

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Mason, C. "Impact of the sensory and postprandial properties of energy drinks on cognition". Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/14459/.

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The impact of energy drinks and their ingredients on cognitive functioning has been of considerable scientific interest in recent years; however studies investigating cognitive effects of energy drink consumption have centred on the postprandial impact, that is the influence of their ingredients once absorbed into the blood. It is possible however, that sensory perception of these drinks, or their ingredients can influence cognition. The four studies outlined in this thesis aim to examine the influences of sensory perception of energy drinks in human volunteers and compare these with the effects observed in the postprandial period on a range of cognitive tasks. Postprandially energy drink treatments were observed to reduce reaction times and improve accuracy compared with a placebo control in a saccadic peripheral conflict task when a 200ms gap was present between a pre-stimulus cue and the stimulus; however when this gap was absent accuracy decreased, suggesting treatment had affected information processing and decision making processes. Sensory perception of a non-carbonated energy drink was observed to improve reaction time and accuracy in a manual choice reaction time task irrespective of gap presence, however an artificially sweetened placebo energy drink had similar effects, but only when the pre-stimulus gap was present. This thesis demonstrates that energy drinks can influence behavioural performance not only by increasing plasma glucose and caffeine levels in the postprandial period, but also through chemosensory perception, an effect elicited by the reward value of taste and flavour perception which is perhaps related to the calorific content of carbohydrates.

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Titus, Jeffery B. "The prediction of cognitive ability from sensory/motor performance : examining the role of sensory/motor performance in the Dean-Woodcock Cognitive Neuropsychology Model". Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1239213.

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The present study investigated the relationship between sensory/motor skills and cognitive abilities in psychiatric and neurologically impaired patients to determine how sensory/motor skills are associated with cognitive abilities. Previous research has demonstrated a significant relationship between performance on sensory/motor tasks and cognition but has failed to examine how well sensory/motor skills can predict specific cognitive performance. Because brain functioning is hierarchical with simpler processes being foundational to the development of more complex functions, it is likely sensory/motor skills can aid in the prediction of specific cognitive abilities. If this is true, then investigation of the relationship between sensory/motor performance and cognition should provide insight into the role of sensory/motor skills in the Dean-Woodcock Cognitive Neuropsychology Model.This study examined the relationship between scores on the Woodcock-Johnson Tests of Cognitive Ability - Revised (WJ-R COG) and scores on the Dean-Woodcock Sensory and Motor Battery (D-WSMB). Participants included 458 patients referred for neuropsychological consultation with neurological and/or psychiatric diagnoses. Results indicated a significant correlation among cognitive scores and sensory/motor scores. Moreover, factor analysis revealed 7 overall factors that account for approximately 65% of the variance. These factors were identified as being thinking ability and processing speed, subcortical functioning, verbal working memory, peripheral processes, tactile kinesthetic thinking (Gtk), visual processing, and simple sensory/motor.Integration of sensory/motor factors into the Dean-Woodcock Cognitive Neuropsychology Model revealed the significant role sensory/motor performance plays in predicting higher-order cognitive abilities. From the analysis it appeared that certain sensory/motor functions were significant contributors to the prediction of specific cognitive abilities. That is, subcortical functioning aided in the prediction of all measured areas of cognition; visual processing contributed to visual-spatial thinking, novel reasoning, and crystallized knowledge; tactile-kinesthetic thinking helped predict visual-spatial thinking, auditory processing, and crystallized knowledge; and simple sensory/motor functioning aided in the explanation of long-term storage-retrieval.These results offer a beginning point for further investigation into the relationship between specific sensory/motor skills and cognitive abilities. Research in this area can provide further insight into the functional organization of the brain and offer application to cognitive outcome in rehabilitation as well as preschool screening.
Department of Educational Psychology

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Dumas, Louise-Émilie. "Les cognitions sensorielle, émotionnelle et sociale dans les troubles de perception et le trouble de stress post traumatique". Electronic Thesis or Diss., Université Côte d'Azur, 2024. http://www.theses.fr/2024COAZ6021.

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Introduction : Les cognitions sensorielle, émotionnelle et sociale représentent le traitement des informations nécessaires à l'adaptation du sujet dans son environnement. Un psycho traumatisme est un évènement menaçant l'intégrité physique et psychique d'un individu et agit comme une « effraction » soudaine et intense de son système cognitif exposé au danger. Cette « effraction » entraine des atteintes cognitives provoquées par des altérations du système de neuromodulation des structures cérébrales impactées. Ces séquelles cognitives provoquent les symptômes qui constituent le trouble de stress post traumatique (TSPT) dont des troubles de perception. Le TSPT est associé à d'autres troubles psychiatriques comorbides dont le trouble psychotique. Notre travail propose l'hypothèse d'une compréhension clinique en « cascade » du psycho traumatisme. Il soutient l'idée que les cognitions sensorielle, émotionnelle et sociale s'articulent entre elles et avec l'environnement et participent à l'évolution du continuum entre psycho traumatisme et trouble psychotique.Méthodes : Nos travaux étudient la place des cognitions sensorielles, émotionnelles et sociales dans les troubles de perception post traumatiques illustrée par deux études de recherche clinique prospectives et longitudinales sur 6 mois. PROJET 1 : Identification des marqueurs de cognitions émotionnelle et sociale associés aux hallucinations acoustico-verbales (HAV) en population pédiatrique générale et en population pédiatrique clinique avec TSPT. PROJET 2 : Impact des troubles olfactifs persistants post Covid-19 sur la qualité de vie, l'expérience hédonique et les dimensions anxieuse et dépressives en population adulte.Résultats : PROJET 1 : L'étude réalisée en population pédiatrique générale a inclus 40 patients d'âge moyen 12,8 ans. Les émotions négatives (tristesse, peur colère) étaient significativement retrouvées dans le groupe avec des HAV persistantes à 6 mois. Les HAV persistantes étaient significativement associées au diagnostic de TSPT (p=0,01). L'étude réalisée en population pédiatrique clinique avec TSPT a inclus 31 patients d'âge moyen 12,9 ans. Les émotions négatives (culpabilité et malveillance des HAV) étaient significativement associées et corrélées à la persistance des HAV. Les émotions négatives (dégout, peur et colère et les diagnostics de dépression et d'anxiété) étaient associées à la persistance du TSPT à 6 mois. La persistance des HAV était significativement associée à l'émergence du diagnostic de trouble psychotique à 6 mois (p=0,01). PROJET 2 : L'étude a inclus 56 patients d'âge moyen 39 ans. Les troubles olfactifs étaient significativement associées à des émotions négatives (qualité de vie, perte de plaisir). Les patients avec une distorsion sensorielle (parosmie, phantosmie) étaient significativement impactés sur le plan émotionnel comparé aux patients qui présentaient une perte sensorielle (anosmie). Bien qu'ils aient retrouvés l'odorat au test psychophysique, les patients qui percevaient d'un trouble olfactif persistant répondaient aux symptômes de TSPT et étaient émotionnellement impactés (qualité de vie, perte de plaisir, anxiété et dépression).Conclusion : Les cognitions sensorielles et émotionnelles, après un évènement traumatique, sont significativement liées entre elles. Leur articulation participent à l'installation et au maintien des troubles de perception. Elles interviennent dans l'évolution de la clinique post traumatique, du TSPT et des troubles psychiatriques associés dont le trouble psychotique. L'évolution des symptômes post traumatiques nécessite une lecture dimensionnelle pour une meilleure compréhension clinique, un suivi préventif des facteurs de risques de mauvaise évolution psychiatrique et une proposition thérapeutique ciblée sur les cognitions sensorielles et émotionnelles
Introduction: Sensory, emotional and social cognition represent the processing of internal and external information required by the subject to adapt to the environment. A psycho-trauma is defined as an event that threatens the physical and psychological integrity of an individual, and acts as a sudden and intense intrusion of the cognitive system exposed to danger. This psycho-traumatic intrusion leads to sensory, emotional and social cognitive damage, caused by alterations in the neuromodulation system of the brain structures affected. These cognitive sequelae give rise to the post-traumatic symptoms that constitute post-traumatic stress disorder (PTSD), including perceptual disorders. PTSD is also associated with other comorbid psychiatric disorders, including psychotic disorders. Our work proposes the hypothesis of a "cascade" clinical understanding of psycho-trauma. It supports the idea that sensory, emotional and social cognition articulate with each other and with the environment, and participate in the evolution of the continuum between psycho-trauma and psychotic disorder.Methods: The aim of our research is to study the role of sensory, emotional and social cognition in post-traumatic perceptual disorders. This work is illustrated by two prospective, longitudinal 6-month clinical research studies. PROJECT 1: Identification of markers of emotional and social cognition associated with acoustic-verbal hallucinations (AVH) in the general pediatric population, then in the clinical pediatric population with PTSD. PROJECT 2: Impact of persistent post-Covid-19 olfactory disorders on quality of life, hedonic experience and anxiety and depression dimensions in an adult population.Results: PROJECT 1: The study, carried out in a general pediatric population, included 40 patients (30 girls, 10 boys) with a mean age of 12.8 years. Negative emotions (sadness, fear, anger) were significantly found in the group with persistent AVH at 6 months. Persistent AVH were significantly associated with the diagnosis of PTSD (p=0.01). The study conducted in a clinical pediatric population with PTSD included 31 patients (25 girls, 6 boys) with a mean age of 12.9 years. Negative emotions (patient guilt and maliciousness of HAV) were significantly associated and correlated with persistence of HAV. Negative emotions (disgust, fear and anger, and diagnoses of depression and anxiety) were also associated with PTSD persistence at 6 months. The persistence of HAV was significantly associated with the emergence of a diagnosis of psychotic disorder at 6 months (p=0.01). PROJECT 2: The study included 56 patients with a mean age of 39 (33 women, 23 men). Olfactory disorders were significantly associated and correlated with negative emotions (quality of life, loss of pleasure). Patients with sensory distortion (parosmia, phantosmia) were more significantly impacted emotionally than patients with no sensory perception (anosmia). Although they "objectively" recovered their sense of smell on the psychophysical test, patients who "subjectively" perceived the persistence of an olfactory disorder responded to PTSD symptoms and were more emotionally impacted (quality of life, loss of pleasure, anxiety and depression).Conclusion: Sensory and emotional cognitions are significantly linked after a traumatic event. Their articulation contributes to the onset and maintenance of perceptual disorders. They are also involved in the development of post-traumatic clinical symptoms, PTSD and other associated psychiatric disorders, including psychotic disorders. The evolution of post-traumatic symptoms requires a dimensional reading for a better clinical understanding, preventive monitoring of risk factors for poor psychiatric evolution, and a therapeutic proposal targeting sensory and emotional cognition

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Vyas, Daivik B. "What a Handful! Electrophysiological Characterization of Sensory and Cognitive Biases on Spatial Attention and Visual Processing". Scholarship @ Claremont, 2016. http://scholarship.claremont.edu/cmc_theses/1321.

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Attention uses sensory inputs and goals to select information from our environment. Monkey electrophysiological literature demonstrates that visuo-tactile bimodal neurons (respond to visual and tactile stimuli presented on/near the hand) facilitate multisensory integration. Human behavioral studies show that hand position/function bias visual attention. Event-related potentials (ERPs) reveal the cortical dynamics coordinating visual inputs, body position, and action goals. Early, sensory ERPs (N1) indicate multisensory integration. Later, cognitive ERPs (P3) reflect task-related processing. Study 1 investigates a discrepancy between monkey and human literatures. Monkey studies demonstrate bimodal neuron responses equidistantly around the whole hand, but human studies demonstrate attentional bias for grasping space. In a visual detection paradigm, participants positioned their hand so target and non-target stimuli appeared near the palm or back of the hand; ERPs were measured. N1 components indicated no amplitude differences between Palm vs. Back conditions, but P3 components revealed greater target vs. non-target differentiation for Palm conditions. Results suggest cortical timing underlies grasping vs. whole hand bias differences: early processing does not differentiate using hand function, but cognitive processing does when stimuli are discriminated for action. Study 2 investigates whether proprioceptive inputs facilitate visual processing. In a visual detection paradigm, participants viewed stimuli presented between occluders blocking view of a hand positioned either near or far from the stimuli. N1 amplitudes were similar for near and far conditions, but P3 amplitudes for target/non-target differences were accentuated for near conditions. Proprioceptive effects emerge later in processing. ERP reveals the cortical dynamics underlying hand position effects on vision.

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Choi, Juwon. "Consumer impulse buying of food at festivals and events: understanding the role of sensory cues". Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32499.

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Doctor of Philosophy
Department of Hospitality Management
Chihyung Ok
Carol W. Shanklin
Impulse buying has gained interest from both researchers and practitioners because of its contribution to sales and profits. The past decade has seen a dramatic increase in the number of mobile food vending in the United States. Open-air selling by vendors may encourage consumers to buy food on impulse. Food sold on streets involves sensory cues that strongly induce impulse buying. Unlike normal buying behavior, impulse buying is greatly affected by emotion, but it may also be explained by cognition. Although impulse buying of food is a prevalent phenomenon, little academic research has been conducted regarding food consumption impulse. Further, there remains a lack of clear understanding of the link between emotions and impulse buying. The purpose of this study was to explore and empirically test consumers’ impulse buying behavior of food from street vendors and to identify determinants such as sensory cues, arousal and pleasure as emotional responses, perceived risk as a cognitive response, and the urge to buy impulsively. In particular, Study 1 proposed a theoretical model identifying the effects of sensory cues on arousal, pleasure, and perceived risk and, in turn, the urge to buy impulsively and impulse buying behavior. Study 2 proposed food neophobia and perceived human crowding as a possible moderator that may function in the relationship between emotions and impulse buying. Data were collected from 361 consumers who were 18 years or older and had purchased food from mobile vendors at a participating festival or event in the United States. The proposed relationships were tested using structural equation modeling and hierarchical multiple regression analysis. In terms of direct effects, Study 1 found that sensory cues were positively related to arousal, pleasure, and the urge to buy impulsively and were negatively related to perceived risk; arousal and pleasure were positively associated with the urge to buy impulsively; perceived risk was negatively associated with the urge to buy impulsively; and the urge to buy impulsively was positively linked with impulse buying behavior. Further, arousal, pleasure, and perceived risk partially mediated the relationship between sensory cues and the urge to buy impulsively. Study 2 concluded that perceived human crowding moderates the effect of arousal and pleasure on the urge to buy impulsively and, in turn, impulse buying behavior. Food neophobia had no moderating effect. The study findings add to the understanding of consumer impulse buying in the context of street food. In addition to its contribution to the literature, practical applications that mobile food businesses could use to attract and retain customers are provided. The study concludes with general discussions of limitations and areas for future research.

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Daugherty, Julie A. "The Relationship between Hearing Status and Cognitive Performance and the Influence of Depressive Symptoms in the Older Adult". Scholar Commons, 2015. https://scholarcommons.usf.edu/etd/5467.

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Hearing loss and cognitive impairment are significant health problems, threatening the independent function of older adults. While there appears to be a strong relationship between the two conditions, the mechanisms underlying this association are complex and are not fully elucidated. The purpose of this secondary analysis was to explore the relationship between hearing ability and cognitive performance in older adults. In addition, this study attempted to examine the role of depressive symptoms in the relationship between hearing loss and cognitive performance. Comprehensive measures of peripheral hearing, central auditory processing and cognitive performance were utilized to examine these relationships in a sample (N = 30) of adults aged 60 years and older. The Geriatric Depression Scale (GDS) was used to assess depressive symptoms. Correlational analyses revealed a statistically significant relationship between central auditory processing and executive function. Statistically significant relationships were also observed between speed of processing and peripheral hearing as well as central auditory processing. No significant relationships were noted between depressive symptoms, hearing acuity and cognitive performance. While the correlation coefficients (r) for several of the hearing and cognitive performance measures were not statistically significant, medium effect sizes were detected, suggesting a moderate association may exist between these variables.

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Montebelli, Alberto. "Towards navigation without sensory inputs: modelling Hesslow?s simulation hypothesis in artificial cognitive agents". Thesis, University of Skövde, School of Humanities and Informatics, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-906.

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In the recent years a growing interest in Cognitive Science has been directed to the cognitive role of the agent's ability to predict the consequences of their actions, without actual engagement with their environment. The creation of an experimental model for Hesslow's simulation hypothesis, based on the use of a simulated adaptive agent and the methods of evolutionary robotics within the general perspective of radical connectionism, is reported in this dissertation. A hierarchical architecture consisting of a mixture of (recurrent) experts is investigated in order to test its ability to produce an 'inner world', functional stand-in for the agent's interactions with its environment. Such a mock world is expected to be rich enough to sustain 'blind navigation', which means navigation based solely on the agent's own internal predictions. The results exhibit the system's vivid internal dynamics, its critical sensitivity to a high number of parameters and, finally, a discrepancy with the declared goal of blind navigation. However, given the dynamical complexity of the system, further analysis and testing appear necessary.

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MacPhail, William R. "Performance Under Pressure: The Effect of Explanatory Style on Sensory-Motor Performance Under Stereotype Threat". Scholarship @ Claremont, 2011. http://scholarship.claremont.edu/cmc_theses/166.

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Do participants with external attribution styles outperform participants with internal explanatory styles in pressure-filled situations? Explicit-monitoring theory suggests that performance becomes impaired when conscious attention is devoted to performing a task normally carried out by automatic processes. Attributing potential failure to an external source (e.g., blaming a sudden gust of wind for a poor golf shot) can decrease the negative effects of stereotype threat, a social-psychological predicament known to engender feelings of stress similar to those experienced in pressure-filled situations, by preventing explicit monitoring from taking place. The current study examined whether individual differences in attribution style, as measured by the Attributional Style Questionnaire, affects golf-putting performance under stereotype threat. The present author hypothesized that participants with external explanatory styles would perform better than participants with internal explanatory styles under stereotype threat, because external participants would be predisposed to create external sources to attribute the cause of poor performance.

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Raju, Namitha. "Effects of Altered Prenatal Sensory Stimulation on Postnatal Contingency Learning in Bobwhite Quail Neonates (Colinus Virginianus)". FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1620.

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Preterm infants are exposed to high levels of modified early sensory experience in the Neonatal Intensive Care Unit (NICU). Reports that preterm infants show deficits in contingency detection and learning when compared to full-term infants (Gekoski, Fagen, & Pearlman, 1984; Haley, Weinberg, & Grunau, 2006) suggest that their exposure to atypical amounts or types of sensory stimulation might contribute to deficits in these critical skills. Experimental modifications of sensory experience are severely limited with human fetuses and preterm infants, and previous studies with precocial bird embryos that develop in ovo have proven useful to assess the effects of modified perinatal sensory experience on subsequent perceptual and cognitive development. In the current study, I assessed whether increasing amounts of prenatal auditory or visual stimulation can interfere with quail neonates’ contingency detection and contingency learning in the days following hatching. Results revealed that augmented prenatal visual stimulation prior to hatching does not disrupt the ability of bobwhite chicks to recognize and prefer information learned in a contingent fashion, whereas augmented prenatal auditory stimulation disrupted the ability of chicks to benefit from contingently presented information. These results suggest that specific types of augmented prenatal stimulation that embryos receive during late prenatal period can impair the ability to learn and remember contingently presented information. These results provide testable developmental hypotheses, with the goal of improving the developmental care and management of preterm neonates in the NICU setting.

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Daniel, François. "Dysfonctionnements de la synergie vergence et accommodation chez les jeunes adultes : impact sur les saccades, la lecture et la cognition". Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCB095/document.

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La qualité de la vision sensorielle, l’aspect oculomoteur et la cognition ont très souvent été abordés de façon individuelle. D’un côté, les désordres de la vergence, liés fréquemment à des désordres de l’accommodation, entraînent des symptômes tels que douleurs, diminution de la qualité de vision mais aussi problèmes d’attention et de concentration, pouvant avoir une incidence sur l’apprentissage. D’un autre côté, les désordres de la vergence sont aussi liés à des problèmes oculomoteurs dans la coordination et la précision des saccades, domaine sur lequel repose l’aptitude à la lecture. L’ambition de cette thèse est d’approfondir ces constats et d’introduire des moyens expérimentaux afin de mettre en évidence les liens entre accommodation/vergence (A/V), contrôle des saccades et leur interférence avec la cognition. Dans une première partie, nous avons étudié l’impact des dysfonctionnements A/V classique et l’impact d’un conflit A/V induit sur les performances au test de Stroop, reconnu pour évaluer certains types de fonctions cognitives, faisant appel aux capacités basiques de lecture et exigeant un déploiement attentionnel élevé. Pour une population d’étudiants, les résultats ont montré des performances diminuées en cas de désordres de la vergence existant et en cas de conflit A/V induit, attestant d’une incidence négative des dysfonctionnements et des déséquilibres A/V induits sur les fonctions exécutives et les processus attentionnels. Ici, l’hypothèse d’une interaction des processus visuels et cognitifs en parallèle apparait plus plausible que celle d’un model sériel, avec une performance cognitive retardée par un problème visuel. Dans un deuxième temps, une réhabilitation de la vergence chez les sujets en présentant des désordres a permis une restauration des capacités, a montré une amélioration de la coordination des saccades et a eu une incidence positive sur l’aspect cognitif pendant la lecture, venant confirmer la théorie d’interférence en parallèle. L’ensemble des travaux apportent des ouvertures de recherches (1) sur le plan théorique, en croisant des domaines comme la neurologie, la psychologie cognitive, l’oculomotricité, l’optométrie et l’orthoptie ; (2) sur le plan clinique, en proposant des tests caractéristiques de dépistage ainsi que des solutions d’amélioration ; (3) sur le plan éducatif, en proposant des pistes pour expliquer l’incidence que le système visuel peut avoir sur les performances académiques
Quality of sensory vision, eye movements and cognition have been broached one by one so far. However, recent studies suggest possible interactions between these fields without clarifying the link. On the one hand, vergence/accommodative (V/A) dysfunctions leads to visual symptoms like sore eyes, blurry or double vision but also problems of attention, concentration, and appear to have a negative impact on academic performances. On the other hand, people diagnosed with vergence disorders also show poor coordination of their saccades, which are essential in reading and cognitive demanding activities. The goal of this thesis is to go into this analysis in depth and to propose experimental ways to evidence the links between V/A disorders, control of the saccades and their influence on cognition. In a first part, we studied the impact of typical V/A disorders and the impact of an induced A/V conflict on the performances during the Stroop test, which is a neurological test known for evaluating cognitive executive functions like inhibition, demanding a high attentional deployment and stimulating basic reading skills. Results show that vergence dysfunctions and V/A inducted conflict have a negative influence on the Stroop performances in students, leading to a diminished control of cognitive functions. These results suggest a more parallel interaction between visual and attentional processes instead of a serial model where vision would be a prerequisite to cognition, slowing down the cognitive processes when disturbed. Secondly, we pursue this theory: vergence rehabilitation in subjects diagnosed with vergence disorders permitted an increase of the vergence capacities, showed an improvement on the coordination of the reading saccades and had a positive influence on the cognitive aspect during reading. This work gives new research possibilities at different level: (1) at a theoretical level, it permits to cross fields like neurology, cognitive psychology, eye movements and optometry; (2) at a clinical level, it suggests typical tests for a more efficient screening and opens new perspectives on solutions to rehabilitate people with V/A disorders; (3) at an educational level, it gives clues on how visual functions could affect academic performances

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15

Baratti, Greta. "ENVIRONMENTAL GEOMETRY IN FISHES AND TORTOISES: EFFECT OF LANDMARKS, BEHAVIOURAL METHODOLOGIES, AND SENSORY CHANNELS ON SPATIAL REORIENTATION". Doctoral thesis, Università degli studi di Trento, 2022. https://hdl.handle.net/11572/356341.

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The present Thesis explored spatial reorientation behaviour of three species of fish (the zebrafish Danio rerio, the redtail splitfin fish Xenotoca eiseni, the goldfish Carassius auratus) and one species of reptiles (the Hermann tortoise Testudo hermanni) to widely assess three issues: 1) the use of environmental geometry with and without landmarks; 2) the role of two geometric tasks, one driven by spontaneous behaviour (“social-cued memory task”) and the other by learning processes (“rewarded exit task”); 3) the involvement of extra-visual sensory channels in visual transparency conditions, and motion patterns. The present Thesis applied behavioural assessments and analyses to pursue a line of comparison, across species, methodologies, and sensory systems. As regards environmental geometry and landmarks in fish and tortoises (Chapter 2), the studies were carried out within several apparatuses, that is, a rectangular opaque arena or two different sized square opaque arenas or a transparent square arena, with conspicuous or local landmarks: Study 1, Conspicuous landmark (blue wall) in zebrafish; Study 2: Local landmarks (corner panels) in zebrafish; Study 3, Environmental geometry in tortoises; Study 4, Conspicuous landmark (blue wall) in tortoises. As regards spontaneous vs. acquired geometric spatial reorientation in fishes (Chapter 3), the studies were carried out within a rectangular or square transparent arena, with or without geometric cues or a 3D landmark: Study 5, Nonvisual environmental geometry in zebrafish, redtail splitfin fish, and goldfish; Study 6, Isolated environmental geometric cues in zebrafish; Study 7, 3D outside landmark (blue cylinder) in zebrafish. As regards extra-visual sensory systems and motion patterns in fish (Chapter 4), one study was carried out within a rectangular transparent arena: Study 8, Lateral line pharmacological ablation in zebrafish. In respect of comparisons among species, overall results suggested that zebrafish, redtail splitfin fish, and goldfish reoriented similarly through transparent surfaces, which defined a distinctive global shape, supporting spatial reorientation under undefined situations (e.g., seek out food within a visually lacking and unenriched environment) as a shared skill among teleosts, despite ecological specificities. Likewise, the Hermann tortoise reoriented within a geometric environment with precision to meet a survival need, suggesting that even non-nomadic species that hibernate for long can benefit from orientation by extended terrain surfaces. In respect of memory tests (“working” vs. “reference”, spontaneous vs. acquired), overall results indicated that the rewarded exit task designed to train fish and tortoise to reorient required learning processes allowing them to overcome natural predispositions to improve other related abilities, such as landmark-use. The dissociation between working and reference memory in spatial domain must be considered highly dependent on task’s demands where attentional factors determine short-term memories and motivational states long-term ones. In respect of sensory channels and motion patterns, overall results revealed that fish and tortoises used modalities driven by touch, in synch with sight, to determine geometric parameters during spatial reorientation. Therefore, a promising link between other vertebrates and humans takes place, in consideration of orientation mechanisms used to face situations of visual deprivation or impairments. The present Thesis may even contribute to a general understanding of reorientation behaviour in phylogenetically remote vertebrate species, thus supporting the widespread use of geometry-grounded tools in everyday activities. This also provides comparative support among species that inhabit on Earth and share cognitive adaptations to deal with similar requests.

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Chang, Acer Yu-Chan. "The role of predictive processing in conscious access and regularity learning across sensory domains". Thesis, University of Sussex, 2017. http://sro.sussex.ac.uk/id/eprint/70234/.

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To increase fitness for survival, organisms not only passively react to environmental changes but also actively predict future events to prepare for potential hazards within their environment. Accumulating evidence indicates that the human brain is a remarkable predictive machine which constantly models causal relationships and predicts future events. This ‘predictive processing' framework, a prediction-based form of Bayesian inference, states that the brain continuously generates and updates predictions about incoming sensory signals. This framework has been showing notable explanatory power in understanding the mechanisms behind both human behaviour and neurophysiological data and elegantly specifies the underlying computational principles of the neural system. However, even though predictive processing has the potential to provide a unified theory of the brain (Karl Friston, 2010), we still have a limited understanding about fundamental aspects of this model, such as how it deals with different types of information, learns statistical regularities and perhaps most fundamentally of all what its relationship to conscious experience is. This thesis aims to investigate the major gaps in our current understanding of the predictive processing framework via a series of studies. Study 1 investigated the fundamental relationship between unconscious statistical inference reflected by predictive processing and conscious access. It demonstrated that predictions that are in line with sensory evidence accelerate conscious access. Study 2 investigated how low level information within the sensory hierarchy is dealt with by predictive processing and regularity learning mechanisms through “perceptual echo” in which the cross-correlation between a sequence of randomly fluctuating luminance values and occipital electrophysiological (EEG) signals exhibits a long-lasting periodic (~100ms cycle) reverberation of the input stimulus. This study identified a new form of regularity learning and the results demonstrate that the perceptual echo may reflect an iterative learning process, governed by predictive processing. Study 3 investigated how supra-modal predictive processing is capable of learning regularities of temporal duration and also temporal predictions about future events. This study revealed a supramodal temporal prediction mechanism which processes auditory and visual temporal information and integrates information from the duration and rhythmic structures of events. Together these studies provide a global picture of predictive processing and regularity learning across differing types of predictive information.

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17

Boudjarane, Mohamed. "Etude observationnelle sur les domaines cognitifs, neurosensoriels et comportementaux de deux populations d'enfants avec des Troubles Envahissants du Développement". Thesis, Brest, 2018. http://www.theses.fr/2018BRES0007.

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L’objet de ce travail était d’observer les effets éventuels d’un nouveau traitement chez des enfants avec des Troubles Envahissants du Développement. Pour cela, nous avons comparé deux groupes d’enfants TED, l’un étant traité l’autre constituant un groupe témoin, à travers des domaines de la cognition, de la sensorialité et des comportements de la vie quotidienne et de la socialisation. Nous avons rassemblé différents outils pour notre méthodologie : questionnaires parentaux, évaluations psychométriques et évaluations psychophysiques.Nous avons également utilisé une approche comparative pour le domaine sensoriel en intégrant un groupe d’enfant au développement typique.Les résultats obtenus dans le cadre de notre travail ont permis de mettre en avant que l’ensemble des comportements évalués n’apparaissaient pas altérés dans notre population d’enfants TED. Nous avons mis en évidence des améliorations accrues des enfants traités concernant leurs capacités visuo-spatiales. Nous avons également constaté que ces enfants présentaient des améliorations de certains processus verbaux. Nous avons confirmé la présence de patterns particuliers de comportements sensoriels chez les enfants TED par rapport à la population neurotypique. En revanche, nous n’avons pas mis en évidence de différence d’évolution entre nos deux groupes d’enfants TED au regard de ces altérations sensorielles. Enfin, les comportements répétés et restreints apparaissaient améliorés de manière accrue chez les enfants TED traités mais nous n’avons pas confirmé les améliorations des comportements sociaux rapportées par les études précédentes. Cette étude a apporté des résultats qui nécessitent d’être scrutés plus en détail, à plus grande échelle
The purpose of this work is to observe the potential effects of new treatment in children with Pervasive Developmental Disorders. For this, we compared two groups of children with PDD, one being treated the other constituting a control group, across domains of cognition, sensory and behaviors of daily life and socialization. We collected different tools for our methodology: parental questionnaires, psychometric assessments and psychophysical assessments. We also used a comparative approach for the sensory domain integrating a typical child development group.The results of this work highlight that whole of the evaluated behaviors did not appear altered in our population of children with PDD. We pointed out increased improvements in treated children regarding their visuospatial abilities. We also found that these children had improvements in some verbal processes. We confirmed the presence of particular patterns of sensory behavior in children with PDD compared to the typically developed population.However, we did not show any difference in evolution of these sensory alterations between our two groups of children with PDD. Finally, repeated and restricted behaviors appeared to be more alleviated in treated PDD children than control PDD children but we did not confirm the improvements in social behaviors reported by previous studies. This study has brought results that need to be scrutinized in more detail, on a larger scale

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18

ALIMONTI, DARIO. "Clinical relationships between motor and cognitive capacities in Parkinson’s Disease". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2023. https://hdl.handle.net/10281/403077.

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OBIETTIVI. Nella sua evoluzione, la malattia di Parkinson mostra una perdita progressiva sia delle funzioni motorie che di quelle cognitive. Nella normale pratica clinica sono a disposizione scale clinometriche per la valutazione di tali aspetti. Diversi studi dimostrano con coerenza l'evidenza del coinvolgimento dell'andatura nella compromissione delle funzioni esecutive. Il presente lavoro si prefigge di analizzare le variazioni motorie e cognitive durante un anno di osservazione in un campione omogeneo di pazienti affetti da malattia di Parkinson. Inoltre, l’utilizzo di un dispositivo elettronico commerciale (G-Walk) per lo studio del cammino, avrà lo scopo di indagarne l’affidabilità nella pratica clinica. MATERIALI. Abbiamo utilizzato scale cliniche standardizzate per valutare i sintomi motori (H&Y, UPDRS-III), cognitivi (MMSE, MoCA, FAB), psichiatrici (BDI-II, BAI) e non motori (RBD Screening Questionnaire, Hyposmia Rating Scale) dei pazienti con malattia di Parkinson. Sono stati presi in considerazione anche altri fattori: dose giornaliera equivalente di levodopa (LEDD), qualità della vita (PDQ-8), motricità (IPAQ-SF), rischio di caduta (scala di Tinetti, scala di Berg ,short-Falls Efficacy Scale). Gli aspetti motori legati alla deambulazione sono altrimenti descritti attraverso l'uso di un dispositivo medico (G-Walk®) indossato in vita dai pazienti durante l'esecuzione di due test di deambulazione standardizzati (eTUG e 6MWT). METODI. Si tratta di uno studio osservazionale condotto su 24 pazienti con malattia di Parkinson, da valutare in modo completo all’arruolamento e ad un anno di distanza. Criteri di inclusione: diagnosi di PD idiopatico; H&Y 2-3; età 55-74 anni. I criteri di esclusione considerano la demenza e quelle condizioni cliniche che possono limitare le capacità locomotorie o la resistenza cardio-polmonare (valutate con la CIRS). RISULTATI. Abbiamo arruolato 24 pazienti (rapporto M/F 15/9), con un'età media di 65,1±5,4 anni, equamente distribuiti per presentazione clinica (rigida-akinetica/tremori 11/13), principalmente nella fase H&Y 2 della malattia (83,3%). Lo studio ha completato il primo anno di osservazione su tutti i pazienti. Sono stati osservati cambiamenti incongruenti con l’aspetto degenerativo della malattia in quanto le caratteristiche cliniche motorie hanno mostrato un miglioramento medio della scala di UPDRS-III. Nel 6MWT, la lunghezza media del passo e la velocità media hanno mostrato invece una tendenza alla diminuzione. Nel eTUG si è osservato un progressivo rallentamento medio nell’esecuzione della prova e nel tempo di turning. Anche i test cognitivi hanno dimostrato una lieve variazione peggiorativa ad un anno. È stato inoltre utilizzato sperimentalmente un altro algoritmo di analisi dei dati motori, sviluppato presso il laboratorio di analisi del movimento (LMAM) dell’univeristà di Losanna (EPFL). Tramite questo algoritmo è stato possibile ricavare i parametri del cammino (velocità, lunghezza del passo, cadenza) anche per la prova di eTUG. Tramite analisi statistica i dati motori ricavati con l’algoritmo del softaware G-Studio (elaborato dal produttore di G-Walk, BTS Bioengineering spa) risultano correlabili e concordi con quelli elaborati da LMAM-algo con l’unica eccezione del calcolo del tempo di turning. DISCUSSIONE. Le variazioni cliniche motorie osservate confermano che le scale cliniche sono utili per una valutazione puntuale dei pazienti, ma non permettono una reale valutazione della progressione di malattia. Queste fluttuazioni cliniche note nella malattia di Parkinson in media sono da considerare in funzione della terapia dopaminergica (in media incrementata nel corso del primo anno di osservazione) e del tipo stesso di scale utilizzate che non permettono una valutazione bilanciata per gli aspetti assiali di malattia (tra cui le capacità di cammino). Queste ultime sembrano ben valutati dall’uso del sensore di movimento.
OJECTIVES. In its evolution, Parkinson's disease shows a progressive loss of both motor and cognitive functions (particularly of the executive and attentional domains). In normal clinical practice, clinometric scales are available for assessing these aspects. For motor aspects alone, there are electronic instruments that provide information on gait characteristics. Several studies consistently demonstrate evidence of the involvement of gait in the impairment of executive functions. The aim of the present work is to analyse motor and cognitive changes during one year of observation in a homogeneous sample of patients with Parkinson's disease. In addition, the use of a commercial electronic device (G-Walk) to study gait will aim to investigate its reliability in clinical practice. MATERIALS. We used standardised clinical scales to assess motor (H&Y, UPDRS-III), cognitive (MMSE, MoCA, FAB), psychiatric (BDI-II, BAI) and non-motor symptoms (RBD Screening Questionnaire, Hyposmia Rating Scale) of patients with Parkinson's disease. Other factors were also taken into account: levodopa equivalent daily dose (LEDD), quality of life (PDQ-8), motility (IPAQ-SF), fall risk (Tinetti's scale, Berg's scale ,short-Falls Efficacy Scale). The motor aspects related to walking are otherwise described through the use of a medical device (G-Walk®) worn around the waist by patients during the performance of two standardised walking tests (6MWT - six minute walking test; eTUG - Timed Up and Go in its 10 metre version). METHODS. This was an observational study conducted on 24 patients with Parkinson's disease, to be fully evaluated at enrolment and one year later. Inclusion criteria: diagnosis of idiopathic PD; H&Y between 2-3; age between 55-74 years. Exclusion criteria considered dementia and those clinical conditions that may limit locomotor abilities or cardiopulmonary endurance (assessed with the Cumulative Illness Rating Scale). RESULTS. We enrolled 24 patients (M/F ratio 15/9), with a mean age of 65.1±5.4 years, equally distributed by clinical presentation (rigid-akinetic/tremor 11/13), mainly in H&Y stage 2 of the disease (83.3%). The study completed the first year of observation on all patients. Incongruent changes with the degenerative aspect of the disease were observed as the clinical motor characteristics showed an average improvement on the UPDRS-III scale (23.75  16.96). In the 6MWT, mean stride length (1.43 --> 1.36 m) and mean speed (1.42 --> 1.36 m/s) showed a decreasing trend. In the eTUG, a progressive average slowdown in test execution (17.92 --> 18.63 s) and turning time (2.08 --> 2.19 s) was observed. The cognitive tests also showed a slight worsening variation at one year. Another motor data analysis algorithm, developed at the Laboratory of Movement Analysis (LMAM) of the University of Lausanne (EPFL), was also used experimentally. Using this algorithm, it was also possible to derive gait parameters (speed, stride length, cadence) for the eTUG test. By means of statistical analysis, the motor data obtained with the G-Studio software algorithm (developed by the manufacturer of the G-Walk, BTS Bioengineering spa) were found to be correlated and in concordance with those processed by LMAM-algo, with the sole exception of the turning time calculation. DISCUSSION. The clinical motor variations observed confirm that the clinical scales are useful for a timely assessment of patients, but do not allow a true assessment of disease progression. These clinical fluctuations known in Parkinson's disease on average are a function of dopaminergic therapy (on average increased during the first year of observation) and the very type of scales used, which do not allow a balanced assessment for axial aspects of disease (including walking ability). The latter appear to be well assessed by the use of the motion sensor.

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Boumenir, Yasmine. "Spatial navigation in real and virtual urban environments: performance and multisensory processing of spatial information in sighted, visually impaired, late and congenitally blind individuals". Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2011. http://tel.archives-ouvertes.fr/tel-00632703.

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Previous studies investigating how humans build reliable spatial knowledge representations allowing them to find their way from one point to another in complex environments have been focused on comparing the relative importance of the two-dimensional visual geometry of routes and intersections, multi-dimensional data from direct exposure with the real world, or verbal symbols and/or instructions. This thesis sheds further light on the multi-dimensional and multi-sensorial aspects by investigating how the cognitive processing of spatial information derived from different sources of sensory and higher order input influences the performance of human observers who have to find their way from memory through complex and non-familiar real-world environments. Three experiments in large-scale urban environments of the real world, and in computer generated representations of these latter (Google Street View), were run to investigate the influence of prior exposure to 2D visual or tactile maps of an itinerary, compared with a single direct experience or verbal instructions, on navigation performances in sighted and/or visually deficient individuals, and in individuals temporarily deprived of vision. Performances were analyzed in terms of time from departure to destination, number of stops, number of wrong turns, and success rates. Potential strategies employed by individuals during navigation and mental mapping abilities were screened on the basis of questionnaires and drawing tests. Subjective levels of psychological stress (experiment 2) were measured to bring to the fore possible differences between men and women in this respect. The results of these experiments show that 2D visual maps, briefly explored prior to navigation, generate better navigation performances compared with poorly scaled virtual representations of a complex real-world environment (experiment 1), the best performances being produced by a single prior exposure to the real-world itinerary. However, brief familiarization with a reliably scaled virtual representation of a non-familiar real-world environment (Google Street View) not only generates optimal navigation in computer generated testing (virtual reality), but also produces better navigation performances when tested in the real-world environment and compared with prior exposure to 2D visual maps (experiment 2). Congenitally blind observers (experiment 3) who have to find their way from memory through a complex non-familiar urban environment perform swiftly and with considerable accuracy after exposure to a 2D tactile map of their itinerary. They are also able to draw a visual image of their itinerary on the basis of the 2D tactile map exposure. Other visually deficient or sighted but blindfolded individuals seem to have greater difficulty in finding their way again than congenitally blind people, regardless of the type of prior exposure to their test itinerary. The findings of this work here are discussed in the light of current hypotheses regarding the presumed intrinsic nature of human spatial representations, replaced herein within a context of working memory models. It is suggested that multi-dimensional temporary storage systems, capable of processing a multitude of sensory input in parallel and with a much larger general capacity than previously considered in terms of working memory limits, need to be taken into account for future research.

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20

Vallet, Guillaume. "Une approche incarnée du vieillissement normal et pathologique : compréhension du fonctionnement mnésique selon les interactions entre mémoire et perception". Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/29087/29087.pdf.

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Le vieillissement et la maladie d’Alzheimer sont caractérisés par des difficultés mnésiques essentiellement épisodiques. Ces difficultés sont associées à leurs altérations sensorielles et perceptives. Ces liens s’expliqueraient naturellement par les approches incarnées de la cognition qui définissent des propriétés et processus communs entre mémoire et perception. Ces approches supposent une émergence dynamique des connaissances à partir d’un système de mémoire unique dans lequel les connaissances sont définies comme ancrées dans leurs propriétés modales, essentiellement celles sensorimotrices. À travers la nature des interactions multisensorielles pour des connaissances familières, ce travail de thèse propose de tester les approches incarnées de la cognition auprès de jeunes adultes, personnes âgées saines et patients souffrant de la maladie d’Alzheimer. Ces interactions sont supposées être indirectes et sémantiques dans les approches multisystémiques, alors qu’elles seraient directes et perceptives pour les approches incarnées. Deux séries d’expériences ont été conduites. Pour chacune d’elle, une batterie complète de tests neuropsychologiques ainsi qu’un paradigme d’amorçage inter-sensoriel (audition vers vision) ont été complétés. L’originalité du paradigme fut l’ajout, pour la moitié des amorces auditives, d’un masque visuel sans signification. L’Expérience 1 reposait sur un format à long terme – deux phases distinctes – alors que l’Expérience 2 sur un format à court terme – amorce et cible présentées dans un même essai. Cette adaptation permet la manipulation de la congruence sémantique afin de tester plus précisément le rôle de l’attention dans ces interactions multisensorielles. Les résultats démontrent un effet d’amorçage inter-sensoriel pour les jeunes adultes et les personnes âgées. Le masque a interféré avec cet effet d’amorçage, mais uniquement lorsque l’amorce et la cible correspondent à une même connaissance. Cette interférence et sa spécificité supportent l’hypothèse d’interactions multisensorielles directes et perceptives ce qui suggèrent que les jeunes adultes comme les personnes âgées auraient des connaissances modales. En revanche, les patients Alzheimer ne présentent pas d’effet d’amorçage alors que celui-ci est de nature perceptive (effet du masque). Ces résultats supportent l’idée d’une déconnexion cérébrale dans la maladie d’Alzheimer. L’ensemble des données permet de supposer que les difficultés mnésiques dans le vieillissement s’expliqueraient essentiellement par une dégradation de la qualité de leurs connaissances, et donc de leur perception. Les troubles mnésiques dans la maladie d’Alzheimer proviendraient quant à eux d’un déficit d’(ré)-intégration dynamique des différentes composantes des connaissances. Cette recherche supporte les approches incarnées de la cognition et démontre la pertinence de ces approches pour des problématiques neuropsychologiques comme celle du vieillissement. Ces approches ouvrent la voie à de nouvelles recherches plaçant les interactions entre mémoire et perception au coeur du fonctionnement mnésique.
Normal aging as Alzheimer’s disease are characterized by memory disorders, primarily for episodic memory. These two populations also present a sensory and perceptive decline, which are strongly correlated with their cognitive impairment. The links between memory and perception may be easily explained in the embodied cognition theory. Indeed, embodiment states that knowledge dynamically emerges from a single memory system in which knowledge remains grounded in its properties, essentially sensory-motor properties. Consequently, perception and memory are closer than previously thought and the links between perception and memory moving to the foreground. The objective of the present research is to assess the embodied cognition theory applied to normal aging and Alzheimer’s disease. To this aim, the nature of the semantic multisensory interactions was tested. According to the multiple memory systems framework, these interactions are indirect and semantic, whereas the embodied cognition theory states that these interactions are direct and perceptual. Young adults, healthy elderly and patients with Alzheimer’s disease completed two experiments. Each experiment was composed of a complete neuropsychological battery and one cross-modal priming paradigm (audition to vision). The novelty of the paradigm was to present a visual meaningless mask for half of the sound primes. Experiment 1 was composed of two distinct phases, whereas the prime and the target were presented in the same trial in Experiment 2. The adaptation of the paradigm in Experiment 2 allowed manipulating the semantic congruency in order to test the attention hypothesis that might underlie the cross-modal interactions. The results demonstrated a significant cross-modal priming effect in young and healthy elderly adults. The mask has interfered with the priming effect only in the semantic congruent situations. The mask interference and its specificity support the direct and perceptual nature hypothesis of the semantic multisensory interactions. This is suggesting that young and elderly adults have modal knowledge. Reversely, the patients with Alzheimer’s disease did not show any priming effect while the effect is perceptual. This result supports the cerebral disconnection hypothesis in Alzheimer’s disease. The data taken together suggest that memory disorders in normal aging could be related to a degradation of the quality of their perception and thus of knowledge. Memory impairments in Alzheimer’s disease might come from an integration disorder to bind dynamically the different components of a memory. The present research support the embodied cognition theory and demonstrates the interest of this kind of approach to explore memory functioning in neuropsychology, such as in aging. These approaches open new avenues of research by focusing on processes rather than systems and by putting on the foreground the interactions between memory and perception.

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21

Derosiere, Gérard. "Vers la discrimination des corrélats neuronaux des déficits d'attention : des Neurosciences Cognitives à l'Ingénierie Cognitive". Thesis, Montpellier 1, 2014. http://www.theses.fr/2014MON1T008/document.

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L'attention focalisée est une fonction cognitive de haut niveau permettant à l'Homme de faciliter sélectivement certaines actions et perceptions. Dans un monde regorgeant de choix d'actions, et de possibilités de perceptions, l'attention focalisée représente une composante vitale de la cognition humaine. Un constat important doit cependant être noté : l'Homme est incapable de maintenir indéfiniment un état stable d'attention focalisée. Cette incapacité est mise en évidence pendant les tâches d'attention soutenue par l'apparition progressive de déficiences sensori-motrices au cours du temps. L'impulsivité motrice augmente alors, ainsi que le temps de réponse aux stimuli impératifs, et la sensibilité perceptive diminue. À l'heure actuelle, les bases neuronales du phénomène restent très peu connues et ce manque de connaissance est clairement perceptible au sein de deux champs disciplinaires - les Neurosciences Cognitives et l'Ingénierie Cognitive. En Neurosciences Cognitives, la question demeure ainsi posée : pourquoi l'Homme est-il incapable de maintenir un niveau de performance sensori-motrice optimal au cours de tâches d'attention soutenue ? En Ingénierie Cognitive, la problématique concerne le développement d'Interfaces Cerveau-Machine (ICM) passives : identifier les marqueurs neuronaux des déficits d'attention permettrait, à terme, de suivre en temps réel l'état cognitif de l'Homme et de l'alerter de la survenue de ces déficits durant son activité. Ces deux problématiques ont été traitées dans cette thèse. Dans un premier temps, je démontre que le maintien d'une attention focalisée sur une stimulation visuelle entraîne une rapide inhibition des aires visuelles corticales. Cette inhibition sensorielle serait liée à l'absence de variation de la stimulation sensorielle. Ainsi, l'inhibition sensorielle serait bénéfique au cours de tâches de recherche visuelle : elle permettrait à l'Homme d'éviter de réexaminer plusieurs fois le même stimulus, le même objet, la même localisation spatiale; mais lorsqu'une attention soutenue est requise, ce mécanisme serait alors à l'origine de l'apparition de déficiences sensorielles. La présence de cette inhibition sensorielle apporte une explication probante à la diminution de sensibilité perceptive et à l'allongement du temps de réaction qui caractérisent le phénomène. Je montre ensuite que l'activité de structures neuronales motrices et d'aires corticales connues pour sous-tendre l'attention focalisée (i.e., tractus cortico-spinal, et aires corticales motrice primaire, préfrontale et pariétale droite) augmente progressivement au cours d'une tâche d'attention soutenue. Ce sur-engagement reflèterait un processus de compensation en réponse au désengagement préalable des aires corticales sensorielles et à la diminution de la qualité des représentations perceptives. Aussi, l'augmentation d'activité des structures neuronales motrices expliquerait l'augmentation de l'impulsivité motrice, une des signatures comportementales des déficits d'attention. Dans un second temps, je teste la possibilité d'exploiter ces corrélats neuronaux des déficits d'attention afin de discriminer deux états attentionnels donnés (i.e., avec ou sans déficits d'attention) au sein d'une ICM passive. Nous avons pour cela appliqué des méthodes de classification supervisées sur des données de spectroscopie proche infra-rouge reflétant l'activité hémodynamique des aires corticales préfrontale et pariétale enregistrées pendant une tâche d'attention soutenue. Nous rapportons des résultats encourageant en termes de performance de classification pour le futur développement d'ICM passives. Pris ensemble, les résultats décrits dans cette thèse apportent une meilleure compréhension des corrélats neuronaux des déficits d'attention et montrent comment cette connaissance peut être exploitée afin de développer des systèmes permettant de limiter la survenue d'accidents et d'incidents liés à l'erreur humaine dans un contexte écologique
Focused attention represents a high-level cognitive function enabling humans to selectively facilitate specific actions and perceptions. In a world full of choices of action, and of perceptual possibilities, focused attention appears to be a vital component of human cognition. One observation however, is worth making: human-beings are unable to maintain stable states of focused attention indefinitely. This inability manifests during sustained attention tasks with the progressive occurrence of sensory-motor deficiencies with time-on-task. The phenomenon - called attention decrement - is characterized by increases in motor impulsivity and in response times to imperative events, and by a reduction in perceptual sensitivity. So far, the neural underpinnings of attention decrement have not been fully elucidated and this lack of knowledge is clearly palpable within two disciplinary fields : Cognitive Neuroscience and Cognitive Engineering. In Cognitive Neuroscience, the associated question is why are human-beings unable to maintain an optimal sensory-motor performance during sustained attention tasks? In Cognitive Engineering, the lack of a complete scientific understanding of attentional issues impacts the development of efficient passive Brain-Computer interfaces (BCI), capable of detecting the occurrence of potentially dangerous attention decrements during the performance of everyday activities. Both issues have been addressed in this thesis. In terms of Cognitive Neuroscience, I demonstrate that sustaining focused attention on a visual stimulation rapidly leads to an inhibition of the visual cortices. This sensory inhibition can be causally related to the lack of changes in perceptual stimulation typically characterizing sustained attention tasks. While the mechanism may be beneficial during visual search tasks as it helps humans avoid processing the same stimulus, the same object, the same location several times, it can lead to the occurrence of sensory deficiencies when sustained attention is required. As such, the sensory inhibition provides a compelling explanation as to the decrease in perceptual sensitivity and to the increase in reaction time that typify attention decrement. I show in a second study that attention decrement is associated with an increase in the activity of motor- and attention-related neural structures (i.e., cortico-spinal tract, primary motor, prefrontal and right parietal cortices). This excessive engagement reflects a compensatory process occurring in response to the sensory disengagement already highlighted and to the related degradation of the quality of perceptual representations. It is notable that the excessive engagement of the motor neural structures with time-on-task provides a potential explanation for the increase in motor impulsivity typifying attention decrement. In terms of application of these new findings, I investigated the potential of exploiting these neural correlates of attention decrement to discriminate between two different attentional states (i.e., with or without attention decrement) through a passive BCI system. To do so, we applied supervised classification analyses on near-infrared spectroscopy signals reflecting the hemodynamic activity of prefrontal and parietal cortices as recorded during a sustained attention task. We achieved relatively promising classification performance results which bode well for the future development of passive BCI. When considered together, the results described in this thesis contribute towards a better understanding of the neural correlates of attention decrement and demonstrate how this novel knowledge can be exploited for the future development of systems which may enable a reduction in accidents and human error-driven incidents in real world environments

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22

Decker, Scott L. "Confirmatory models of sensory/motor and cognitive constructs". Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1233197.

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This study examined the relationship between neuropsychological constructs of sensory-motor functioning and cognitive ability constructs in the Cattell-Horn-Carroll (CHC) (Carroll, 1993) theory. Two studies were conducted For the first study, the Dean-Woodcock Sensory Motor Battery (SMB) (Dean & Woodcock, 1999) was administered to 800 individuals. A factor analysis and a confirmatory factor analysis were used to investigate and develop a factor structure of the SMB. Results from this study suggest sensory and motor tests significantly share common variance and a hierarchical, multifactorial model that included a higher-order factor of both sensory and motor tests best fit the data. The second study examined the SMB model, developed in the first study, in relation to the CHC (Cattell-Horn-Carroll) model of cognitive abilities, as measured by the Woodcock-Johnson Revised Tests of Cognitive Abilities (WJ-R) (McGrew, Werder, & Woodcock, 1991). For this study, the SMB and the WJ-R was administered to 411 individuals. A confirmatory model was tested that included the higher-order factor of the SMB as a broad ability within the CHC model. Results from this analysis suggest the higher order factor of the SMB does have a significant relationship with overall measures of cognitive ability of a similar level to other broad abilities in the CHC model, and significantly improves the fit of CHC model. These results support Roberts, Pallier, and Goffs (1999) argument for the inclusion of an additional broad ability in the CHC taxonomy that represents sensory and motor functioning. Additionally, this study provides empirical support for the utility of including neuropsychological tests of sensory and motor functioning in a comprehensive assessment of cognitive abilities (Dean & Woodcock, 1999). The implications for neuropsychological and psychometric assessment are discussed.
Department of Educational Psychology

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23

Goh, Hock Guan. "Cognitive wireless sensor networks (CogWSNs)". Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24216.

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Cognitive Wireless Sensor Networks (CogWSNs) are an adaptive learning based wireless sensor network relying on cognitive computational processes to provide a dynamic capability in configuring the network. The network is formed by sensor nodes equipped with cognitive modules with awareness of their operating environment. If the performance of the sensor network does not meet requirements during operation, a corrective action is derived from stored network knowledge to improve performance. After the action is implemented, feedback on the action taken is evaluated to determine the level of improvement. Example functions within CogWSNs can be as simple as to provide robust connectivity or as complex as to negotiate additional resources from neighbouring network groups with the goal of forwarding application-critical data. In this work, the concept of CogWSNs is defined and its decision processes and supporting architecture proposed. The decision role combines the Problem Solving cognitive process from A Layered Reference Model of the Brain and Polya Concept, consisting of Observe, Plan, Implement, and Evaluate phases. The architecture comprises a Transceiver, Transducer, and Power Supply virtual modules coordinated by the CogWSN's decision process together with intervention, if necessary, by a user. Three types of CogWSN modules are designed based on different implementation considerations: Rule-based CogWSN, Supervised CogWSN, and Reinforcement CogWSN. Verification and comparison for these modules are executed through case studies with focus on power transmission and communication slot allocation. Results show that all three modules are able to achieve targeted connectivity and maintain utilisation of slots at acceptable data rates.

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24

Barnaby, Alice. "Light touches : cultural practices of illumination, London 1780-1840". Thesis, University of Exeter, 2009. http://hdl.handle.net/10036/3037.

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In the last decades of the eighteenth century, urban lives were touched by a series of innovations in the technology and aesthetics of illumination. Unfamiliar combinations of new fuel sources and auxiliary equipment (for example, curtains, blinds, glass, mirrors and lampshades) meant that cities looked and felt different during both the day and the night. The spheres of elite, popular, public and private culture explored, exploited and were fascinated by the cultural value of light. Through four case studies in the aesthetics of urban illumination, my thesis demonstrates how the acquisition of skills for the manipulation of transparent and reflective surfaces were crucial when negotiating a balance between self-expression and standards of taste, morality, gender and class. Rather than relying upon canonical examples of the period’s fascination with light, such as the high Romantic idealization of nature’s sunrises and sunsets, my thesis investigates more everyday encounters with light in the built environment: the fashionably genteel pastime of transparent painting; the gendering of light to design both domestic interiors and female identity; the appropriation of patrician top-lighting for public buildings of education and exhibition; and the popularity of illuminated spectacles in commercial pleasure gardens. I argue that these new possibilities of lighting temporarily enabled new possibilities of subjectivity. My historical phenomenology suggests that the formation of perception between 1780 and 1840 was actively directed towards changes in the world through a finely-attuned consciousness of light.

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25

Wright, Craig, e n/a. "Sensory Processing in Dyslexic Children". Griffith University. School of Psychology, 2005. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20061018.153411.

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This study tested the prediction that a group of dyslexic children (n = 70) would be less sensitive to auditory and visual temporal stimuli than a control group (n = 52). In the auditory domain, detection thresholds for 2 Hz FM, 2 Hz AM and 20 Hz AM were assessed. The modulations in these stimuli are detected on the basis of temporal cues. In contrast, the modulations in the control stimulus 240 Hz FM modulate too rapidly to be detected with temporal cues. The dyslexic group were significantly less sensitive than the control group to the temporal and non-temporal measures at initial testing (Phase 1) and again nine months later (Phase 4). These data demonstrated that the auditory deficit in the dyslexic group was more general in nature than had previously been suggested. In the visual domain, sensitivity to global coherent motion was assessed. The dyslexic group were significantly less sensitive than the control group on this measure at both phases of the study. Despite the overall between group differences, the magnitude of the effects were low to moderate. There was also substantial overlap between the performance of the two groups on the sensory processing measures. A deviance analysis was conducted to determine the proportion of dyslexic individuals who had sensory processing deficits. When data from each phase was examined separately, the incidence of sensory processing deficits in the dyslexic group was comparable to previous studies. However, when the data from both phases was combined, only 5-18% of the dyslexic group had impairments on any of the sensory tasks that were stable across time. Nevertheless, these results do not preclude sensory processing making a contribution to reading difficulties in some children. When the relationship between sensory processing thresholds and reading ability was considered, sensitivity to auditory and visual temporal measures accounted for significant unique variance in phonological processing, orthographic coding and overall reading skill, even after accounting for IQ and vigilance. This study was also tested the prediction that visual attention can explain the link between visual temporal processing and reading. Vidyasagar (1999) proposed that the magnocellular (M) system, which processes temporal stimuli (e.g., motion), is also important for efficient functioning of an attentional spotlight. This spotlight is proposed to arise in parietal cortex (a major endpoint of the M system), and is involved in highlighting areas for detailed visual processing when performing visual tasks, such as visual search or reading. It was predicted that only those dyslexic participants with motion detection impairments would also be impaired on a serial search task that required the attentional spotlight. On average, the dyslexic group had significantly slower serial search than the control group. However, the magnitude of effect was small and a deviance analysis demonstrated that only 8.5% of the dyslexic group had stable impairments relative to the control group. Furthermore, only one of the six dyslexic participants with a visual attention impairment had a co-existing deficit in detecting coherent motion. Thus, visual attention deficits of this type appear to exist independently of coherent motion deficits. This study also provided important evidence on the reliability of measurement for the sensory processing tasks. The data showed that the test-retest reliability of the sensory measures was only moderate over a nine month period. Test-retest for other cognitive measures over the same time frame was high - including that for an orthographic coding task, which had similar procedure and task demands to the sensory measures. The results also demonstrated that a high proportion of participants in both groups performed inconsistently across time (i.e., they had a threshold indicative of a deficit at one phase and performance within normal limits at the other). Up to 32% of the dyslexic group and 19% of the control group had inconsistent performance on the sensory measures across time. The importance of developing more reliable methods of estimating sensory sensitivity is discussed, as is the need for normative data on sensory processing tasks in order to more accurately make decisions about the incidence of sensory deficits. In summary, this study provided evidence for a relationship between sensory processing and reading. However, the current data demonstrated that sensory processing deficits are not characteristic of all dyslexic individuals. Future research should focus on explaining why only a sub-group of dyslexics have sensory deficits, and also why some control participants have deficits.

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26

Wright, Craig. "Sensory Processing in Dyslexic Children". Thesis, Griffith University, 2005. http://hdl.handle.net/10072/366474.

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This study tested the prediction that a group of dyslexic children (n = 70) would be less sensitive to auditory and visual temporal stimuli than a control group (n = 52). In the auditory domain, detection thresholds for 2 Hz FM, 2 Hz AM and 20 Hz AM were assessed. The modulations in these stimuli are detected on the basis of temporal cues. In contrast, the modulations in the control stimulus 240 Hz FM modulate too rapidly to be detected with temporal cues. The dyslexic group were significantly less sensitive than the control group to the temporal and non-temporal measures at initial testing (Phase 1) and again nine months later (Phase 4). These data demonstrated that the auditory deficit in the dyslexic group was more general in nature than had previously been suggested. In the visual domain, sensitivity to global coherent motion was assessed. The dyslexic group were significantly less sensitive than the control group on this measure at both phases of the study. Despite the overall between group differences, the magnitude of the effects were low to moderate. There was also substantial overlap between the performance of the two groups on the sensory processing measures. A deviance analysis was conducted to determine the proportion of dyslexic individuals who had sensory processing deficits. When data from each phase was examined separately, the incidence of sensory processing deficits in the dyslexic group was comparable to previous studies. However, when the data from both phases was combined, only 5-18% of the dyslexic group had impairments on any of the sensory tasks that were stable across time. Nevertheless, these results do not preclude sensory processing making a contribution to reading difficulties in some children. When the relationship between sensory processing thresholds and reading ability was considered, sensitivity to auditory and visual temporal measures accounted for significant unique variance in phonological processing, orthographic coding and overall reading skill, even after accounting for IQ and vigilance. This study was also tested the prediction that visual attention can explain the link between visual temporal processing and reading. Vidyasagar (1999) proposed that the magnocellular (M) system, which processes temporal stimuli (e.g., motion), is also important for efficient functioning of an attentional spotlight. This spotlight is proposed to arise in parietal cortex (a major endpoint of the M system), and is involved in highlighting areas for detailed visual processing when performing visual tasks, such as visual search or reading. It was predicted that only those dyslexic participants with motion detection impairments would also be impaired on a serial search task that required the attentional spotlight. On average, the dyslexic group had significantly slower serial search than the control group. However, the magnitude of effect was small and a deviance analysis demonstrated that only 8.5% of the dyslexic group had stable impairments relative to the control group. Furthermore, only one of the six dyslexic participants with a visual attention impairment had a co-existing deficit in detecting coherent motion. Thus, visual attention deficits of this type appear to exist independently of coherent motion deficits. This study also provided important evidence on the reliability of measurement for the sensory processing tasks. The data showed that the test-retest reliability of the sensory measures was only moderate over a nine month period. Test-retest for other cognitive measures over the same time frame was high - including that for an orthographic coding task, which had similar procedure and task demands to the sensory measures. The results also demonstrated that a high proportion of participants in both groups performed inconsistently across time (i.e., they had a threshold indicative of a deficit at one phase and performance within normal limits at the other). Up to 32% of the dyslexic group and 19% of the control group had inconsistent performance on the sensory measures across time. The importance of developing more reliable methods of estimating sensory sensitivity is discussed, as is the need for normative data on sensory processing tasks in order to more accurately make decisions about the incidence of sensory deficits. In summary, this study provided evidence for a relationship between sensory processing and reading. However, the current data demonstrated that sensory processing deficits are not characteristic of all dyslexic individuals. Future research should focus on explaining why only a sub-group of dyslexics have sensory deficits, and also why some control participants have deficits.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Psychology
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27

Fox, Elizabeth Lynn. "Cognitive Analysis of Multi-sensor Information". Wright State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=wright1435681970.

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28

Shankardass, Aditi. "Neurophysiological evidence of sensory and cognitive deficits in dyslexia". Thesis, University of Sheffield, 2004. http://etheses.whiterose.ac.uk/14482/.

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For those engaged in trying to understand the cause of dyslexia, these are interesting times. There is increasing evidence that dyslexia may result from a deficit in the brain's ability to process general visual and auditory information, which may subsequently contribute to observed language difficulties. While some suggest that this processing deficit is confined to lower perceptual levels, others propose that it extends to higher cognitive levels of attention and learning. So far there is surprisingly little evidence of research wherein both modalities, both processing levels and various stimulus features have been tested in the same set of dyslexics using electrophysiological measures. This was the purpose of this research. In four studies, event related potentials were recorded from dyslexic and control brains during the non-attentive and attentive discrimination of various visual and auditory stimuli. Average dyslexic-control ERP comparisons were made for sensory N 1 and MMN waves in the passive, and cognitive P2, N2 and P3 waves in the active response conditions. Dyslexics had attenuated MMNs during the pre-attentive discrimination of changes in peripheral visual field, auditory frequency and rapid auditory sequences but not auditory duration. Moreover, dyslexics had abnormal P2 or P3 waves during the attentive discrimination of all visual and auditory stimuli. Finally, the previously attenuated MMN to frequency discrimination was enhanced after attentive practice. The feature-specific MMN abnormalities suggest a highly selective, multi-modal, perceptual dysfunction in dyslexics, as predicted by the pan-sensory deficit theory. However, the ubiquitous task-related P2 and P3 abnormalities suggest that their deficits also extend to higher cognitive domains, as predicted by the automatization/cerebellar deficit theory. The subsequent MMN enhancement suggests practice-induced improvements in their perceptual acuity. These findings suggest that dyslexia is a multilevel syndrome: the same dyslexics have problems in both domains: visual and auditory, and at both processing levels: sensory and cognitive.

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29

Vergilino-Perez, Dorine. "Les transformations sensori-motrices pendant la lecture". Paris 5, 2001. http://www.theses.fr/2001PA05H038.

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L'objectif de cette thèse est de déterminer à quel moment et dans quel système de coordonnées s'effectuent les transformations sensori-motrices à la base de la planification des saccades en situation de lecture. Une première série d'expériences utilisant un paradigme de saccades mémorisées et visuellement guidées démontre que le plan moteur de la séquence de saccades diffère selon l'action planifiée sur le mot -atteindre un nouveau mot-cible ou explorer un même mot à l'aide de pluieurs saccades- lorsque deux saccades sont planifiées vers deux mots-cibles, la position de la seconde cible est encodée au moment de sa présentation en coordonnées centrées sur la tête et réactualisée après la première saccade en fonction de la nouvelle position de l'oeil dans l'orbite. La seconde saccade est calculée pour atteindre le centre du second mot. Lorsqu'une séquence de deux saccades est planifiée dans un même mot, la seconde saccade intra-mot est encodée en coordonnées oculocentrées sous la forme d'un vecteur moteur fixe non réajusté en fonction de la position de la première fixation. Une seconde série d'expériences examinant la flexibilité des plans moteurs en fonction des modifications des propriétés spatiales des stimuli met en évidence une préplanification de la saccade intra-mot avant le déclenchement de la première saccade sur la base de la longueur du mot intégrée en périphérie. L'ensemble de ces résultats démontre que l'action envisagée sur l'objet conditionne non seulement la nature des informations utilisées dans le codage de l'action mais également le moment où ces informations sont traduites en une représentation motrice
The goal of this thesis is to specify when and in which coordinate system the sensorimotor transformations involved in the planning of saccades in reading are carried out. The first series of experiments uses a visually and memory-guided saccades paradigm. The results demonstrate that readers hold an internal motor plan in at least two different reference frames that are specific to the action to be performed : to aim for a new target word or to read it over with a second fixation. When a word is selected as a target for the next saccade, the spatial location of the second target is encoded in head-centered coordinates before the first saccade. Then, the second saccade is updated with respect to the current eye position after the first saccade in order to aim a fonctional target location in the second word that is the word's center. (. . . )

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30

Wintermute, Cody Lee. "Observing P300 Amplitudes in Multiple Sensory Channels using Cognitive Probing". Wright State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=wright1598375415421172.

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31

Kemp, Jennifer. "Douleur et vieillissement : exploration électrophysiologique des sous-jacents périphériques et centraux". Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAJ070/document.

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Le vieillissement s’accompagne de changements de la perception de la douleur, avec notamment des modifications des seuils de douleur. L’objectif de ce travail de thèse était de déterminer les mécanismes sous-jacents à ces changements. Nous nous sommes basés sur l’étude de deux indicateurs : des données psychophysiques (i.e., jugements perceptifs) et des mesures électrophysiologiques. Nos premiers tests ont confirmé une diminution de la douleur perçue chez les séniors. Une série de 4 expérimentations nous a ensuite permis de montrer que l'augmentation du seuil de douleur chez les séniors avait à la fois une origine périphérique (i.e., atteinte des fibres sensorielles) et centrale (i.e., modification cérébrale). Au niveau périphérique, nous avons montré que seules les fibres myélinisées (fibres A delta) semblent altérées par le vieillissement. Au niveau central, nos résultats vont dans le sens d'un seuil de douleur augmenté en raison d'un déficit attentionnel chez les séniors
Non-pathological ageing is often associated with changes in pain perception and especially with changes in pain thresholds. The aim of this thesis was to determine the underlying mechanisms of these changes. We analyzed two complementary indicators: psychophysical data, by the means of perceptual judgments, and electrophysiological measurements. Our first tests confirmed a decrease of older subjects' perceived pain, compared to that of younger adults. A series of 4 experiments further allowed us to show that the increase in older adults' pain threshold has both a peripheral (i.e., impairment of peripheral sensory fibers) and a central (i.e., modifications at a cerebral level) origin. At the peripheral level, we found that only myelinated fibers (i.e., A-delta fibers) seem to be affected by ageing. At a central level, our results indicate that the increase in pain thresholds is due to difficulties in allocating attentional resources to the stimulation in the elderly

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32

Tormo, Peiró Julia Alba. "Spectrum sensing based on specialized microcontroller based white space sensors : Measuring spectrum occupancy using a distributed sensor grid". Thesis, KTH, Radio Systems Laboratory (RS Lab), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-124555.

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The continuing increase in the adoption and use of wireless technology aggravates the problem of spectrum scarcity due to the way we utilize the spectrum. The radio spectrum is a limited resource regulated by governmental agencies according to a fixed spectrum assignment policy. However, many studies show that this fixed radio frequency allocation leads to significant underutilization of the radio spectrum creating artificial scarcity, as most of the allocated spectrum is not used all of the time in every location. To meet services growing demands, efficient use of the spectrum is essential. Therefore, there is a need to estimate the radio spectrum utilization in several locations and during different periods of time in order to opportunistically exploit the existing wireless spectrum. Cognitive radio technology aims to search for those portions of the radio spectrum that are assigned to a specific service, but are unused during a specific time and at specific location in order to share these white spaces and thus to reduce the radio spectrum inefficiency. In this thesis, we study spectrum utilization in the frequency range from 790MHz to 925MHz. The spectrum sensing has been realized using a number of specialized microcontroller based white space sensors which utilize energy detection, situated in different locations of a building in Kista, Sweden. The occupancy of the frequency bands in this chunk of the spectrum is quantified as the fraction of samples with a power level greater than a threshold. The results from these spectrum measurements show that a significant amount of spectrum in this scanned range around the building is inefficiently used all the time.
Den senaste tidens ökning av trådlös teknik förvärrar problemet med spektrumbrist på grund av hur vi använder den. Det radiospektrum är en begränsad resurs som regleras av statliga myndigheter enligt en fast spektrumtilldelningen politik. Men många studier visar att den fasta frekvensplan leder till betydande underutnyttjande av radiospektrum och skapar en konstgjord brist eftersom de flesta av de tilldelade spektrumet inte används hela tiden i varje platsen. För att uppfylla tjänster ökade krav, är viktigt en effektiv användning av spektrumet. Därför finns det ett behov av att uppskatta användningen av radiospektrum i flera platser och i olika tidsperioder för att kunna utnyttja den befintliga trådlösa spektrumet i opportunistiskt sätt. Kognitiv radio teknologi syftar till att söka efter dessa delar av radiospektrum som tilldelas till en konkret tjänst och är oanvända i en viss tid och på viss plats för att dela dessa vita ytor och därför lösa radio spektrum ineffektivitet problem. I denna uppsats studerar vi spektrumanvändning i frekvensområdet från 790 MHz till 925 MHz. Spektrat avkänning har utförts med hjälp av ett antal specialiserade mikrokontroller blanktecken sensorer vilka utnyttjar energin upptäckt, som ligger på olika platser i en byggnad i Kista, Sverige. Uthyrningsgraden av frekvensbanden i denna del av spektrumet kvantifieras som antalet prover med en effektnivå överstiger en tröskel. Resultaten från spektrat mätningarna visar att en betydande del av spektrumet i denna scannade intervall ineffektivt används hela tiden.

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33

Poletti, Céline. "Les variations stratégiques dans les tâches cognitives et motrices au cours du vieillissement". Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM3102.

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Des travaux récents ont montré que les relations entre le fonctionnement cognitif et sensori-moteur étaient de plus en fortes au cours du vieillissement, suggérant que des mécanismes communs seraient responsables du déclin avec l’âge des performances cognitives et sensori-motrices. Des variations quantitatives telles que la diminution avec l’âge de la vitesse de traitement ont été proposées comme cause commune pour expliquer le ralentissement cognitif et sensori-moteur. Toutefois, nous ignorons toujours comment ces variations quantitatives pourraient influencer les variations qualitatives au cours du vieillissement. L’objectif de cette thèse était de décrire les variations stratégiques liées à l’âge dans le domaine sensori-moteur d’une part, et de déterminer si les variations stratégiques observées dans le domaine cognitif pouvaient être communes aux variations stratégiques dans le domaine sensori-moteur, d’autre part. Nos données répliquent les principaux résultats observés dans les domaines cognitifs concernant les différences liées à l’âge dans les différentes variations stratégiques ainsi que les phénomènes associés à des variations telles que les effets de difficulté séquentielle, suggérant l’implication de ressources communes telles que les fonctions exécutives. Nos données montrent également une amplification de ces variations stratégiques au cours du vieillissement pathologique et suggèrent une amélioration de l’exécution stratégique après un entraînement. Les résultats présentés dans cette thèse permettent une meilleure compréhension des mécanismes cognitifs sous-jacents au comportement sensori-moteur des adultes jeunes et âgés durant la tâche de Fitts
Recent studies have demonstrated that the relationship between cognitive and sensori-motor functioning is becoming stronger during aging, suggesting that common mechanisms could be responsible for age-related decline in cognitive and sensori-motor performance. Quantitative variations in aging, such as decreased information processing speed have been proposed as a common cause to explain cognitive and sensori-motor slowing. However, we do not know how these quantitative variations can influence the qualitative changes during aging. The main objective of this thesis was to describe age-related strategic changes in the sensori-motor domain and furthermore to determine whether these strategic changes in the sensori-motor domain share similar strategic variations with cognitive domain. To achieve this objective, a total of five studies were conducted where both young and older adults performed the Fitts' task. Our data replicated previous findings relative to those observed in the cognitive domain. On the one hand, age-related differences in strategy repertoire, strategy distribution and strategy execution were found. On the other hand, phenomenon associated with these variations, such as strategy sequential difficulty effects were also observed, suggesting involvement of common resources (i.e., executive functions). Additionally, we showed an amplification of these strategic variations in pathological aging and an improvement in strategic execution after training. These results provide a better understanding of the underlying cognitive mechanisms in young and older adults’ sensori-motor behavior during the Fitts’ task

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34

Rogers, Susan. "The influence of sensory and cognitive consonance/ dissonance on musical signal processing". Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=95035.

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This thesis investigates possible origins of the distinction between consonant and dissonant auditory events and how persons with and without formal musical training judge the distinction. Two studies comprising six experiments used behavioral methods to explore perceptual and cognitive differences between musicians and nonmusicians. The first three experiments concern the qualitative assessment of auditory roughness a primary component of sensory dissonance. The remaining three experiments concern short-term memory for musical intervals as distinguished by their properties of consonance and dissonance. An original contribution of this thesis is to quantify several differences that musical training confers upon both bottom-up (sensory-driven) and top-down (knowledge-driven) processing of musical sounds. These studies show that knowledge of a tonal hierarchy in a given culture cannot be reliably dissociated from the evaluation of a musical sound's features. Moreover, they show that robust, accurate auditory short-term memory exceeds the duration previously reported in the literature. These findings are relevant to theories of music perception and cognition, auditory short-term memory, and the psychophysical scaling of auditory event properties.
Dans cette thèse nous étudions les origines possibles de la distinction entre événements auditifs consonants et dissonants, ainsi que la façon dont cette distinction est révélée dans le traitement auditif par les personnes ayant une formation musicale ou pas. Deux études comprenant six expériences ont employé des méthodes comportementales pour explorer les différences perceptives et cognitives entre musiciens et non musiciens. Les trois premières expériences concernent l'évaluation qualitative de la rugosité auditives un composant élémentaire de la dissonance sensorielle. Les autres trois expériences concernent les différences de la mémoire à court terme entre les intervalles musicaux consonants et dissonants. Une contribution originale de cette thèse est de quantifier plusieurs différences que la formation musicale confèrent sur les traitements ascendants (conduits par les sensations) et descendants (conduits par les connaissances) des sons musicaux. Ces études montrent que les connaissances sur la hiérarchie tonale dans une culture donnée ne peuvent pas être fiablement dissociées de l'évaluation des attributs d'un son musical et que la durée de la mémoire auditive à court terme, qui est robuste et précise, excède celle rapportée précèdemment dans la littérature.

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Mortada, Mohamad Rida. "Multi-hop routing for cognitive radio sensor network". Thesis, Brest, École nationale supérieure de techniques avancées Bretagne, 2021. http://www.theses.fr/2021ENTA0010.

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Le réseau de capteurs sans fil (WSN) se compose d'un grand nombre de minuscules dispositifs appelés nœuds, et ces nœuds sont généralement limités en puissance et ils sont déployés de manière aléatoire dans une zone géographique à des fins de surveillance. En raison du grand nombre de nœuds dans le WSN, leur demande en ressources de fréquence devient un véritable défi en raison de la rareté du spectre. La radio cognitive (CR) a été introduite pour améliorer l'efficacité spectrale. La CR classe les utilisateurs entre l'utilisateur principal (PU) qui détient une licence sur une bande passante du spectre et l'utilisateur secondaire (SU), c'est-à-dire un utilisateur opportuniste. L'intégration de CR dans WSN se traduit par un réseau de capteurs radio cognitifs (CRSN). Dans le CRSN, les nœuds se comportent comme des SU. Cependant, l'adoption du CRSN peut être confrontée à plusieurs défis. En effet, les nœuds du réseau peuvent arrêter de transmettre pour éviter toute interférence nuisible pour PU. De plus, la contrainte de consommation d'énergie doit être respectée. D'autres fonctionnalités peuvent être affectées par l'adoption du CRSN, telles que le processus de regroupement et l'agrégation de données dans le réseau, en particulier dans un CRSN basé sur un routage multi-sauts. Dans ce manuscrit, nous abordons les défis du CRSN à différents niveaux. Premièrement, le regroupement des nœuds améliore l'efficacité du réseau. En pratique, le regroupement des nœuds du réseau permet d'économiser de l'énergie lors de la transmission des données. Ainsi, nous étudions le nombre optimal de clusters dans le réseau en fonction de la consommation d'énergie lors de la transmission de données et de la détection du spectre pour prolonger la durée de vie du réseau. Ensuite, nous présentons LIBRO, un nouveau protocole de routage multi-sauts montant basé sur les informations de localisation géographique. LIBRO assure la livraison de paquets de données rectifiés dans des réseaux denses sans connaissance de la topologie ou des nœuds de chemin. Enfin, nous avons utilisé LIBRO et la technique de récupération d'énergie pour prolonger la durée de vie du CRSN. Ainsi, en résolvant un problème d'optimisation joignant la probabilité de collision, la consommation d'énergie, le délai de livraison des paquets et le taux de livraison des paquets, les paramètres appropriés sont trouvés. [Google traduction]
The Wireless Sensor Network (WSN) consists of a large number of tiny devices called nodes, and these nodes are generally limited in power and they are randomly deployed in a geographical area for monitoring purpose. Because of the large number of nodes in the WSN, their demand on the frequency resources becomes a real challenge due to the spectrum scarcity. Cognitive Radio (CR) was introduced to enhance the spectral efficiency. The CR classifies users into the Primary User (PU) that holds a license over a spectrum bandwidth, and the Secondary User (SU), i.e., an opportunistic user. The integration of CR into WSN results in a cognitive radio sensor network (CRSN). In CRSN, the nodes behave as SUs. However,the adoption of CRSN may face several challenges. Indeed, network nodes may stop transmitting to avoid any harmful interference for PU. In addition, energy consumption constraint should be respected. Other features may be impacted by the adoption of CRSN, such as the clustering process and the in-network data aggregation, especially in a multi-hop routing based CRSN. In this manuscript, we tackle the challenges of the CRSN from different levels. Firstly, clustering nodes enhances network efficiency. In practice, grouping the network nodes saves energy during data transmission. Thus, we investigate the optimal number of clusters in the network based on energy consumption during data transmission and spectrum sensing to extend network lifespan. Then, we present LIBRO, a new uplink multi-hop routing protocol based on the geographical location information. LIBRO ensures delivery of rectified data packets in dense networks without knowledge of topology or path nodes. Finally, we used LIBRO and the energy harvesting technique to extend the CRSN's lifespan. Thus, by solving an optimization problem jointing the collision probability, energy consumption, packet delivery delay and packet delivery ratio, the appropriate parameters are found

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36

Men, Shaoyang. "Spectrum sensing techniques in cognitive wireless sensor networks". Thesis, Nantes, 2016. http://www.theses.fr/2016NANT4015/document.

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Dans cette thèse, nous étudions l’optimisation des techniques de détection du spectre dans le contexte des réseaux cognitifs de capteurs sans fil. L’objectif de ces techniques est de déterminer l’occupation ou la disponibilité du canal. Tout d’abord, une vue d’ensemble des techniques de détection du spectre développées dans la littérature est fournie. Ensuite, les défis posés par le cadre applicatif des réseaux de capteurs sans fil sont décrits ; il s’agit de considérer dans le processus de décision les ressources et les capacités limitées des noeuds du réseau. Ainsi, plusieurs méthodes de détection du spectre sont proposées dans cette thèse. Certaines s’appliquent uniquement localement au niveau d’un noeud, tandis que d’autres mettent en oeuvre une stratégie coopérative entre les noeuds pour une meilleure détection du spectre. En premier lieu, afin de diminuer la durée d’observation du canal et de réduire la consommation d’énergie, le problème adressé est celui de la détection du spectre à partir d’un très petit nombre d’échantillons. Deux techniques reposant sur la statistique des échantillons sont donc proposées afin d’améliorer la décision concernant la disponibilité ou non du canal : une détection locale du spectre basée sur un test Goodness-of-Fit et, une détection coopérative du spectre basée sur la théorie des croyances de Dempster-Shafer. Puis, le problème de l’optimisation de l’efficacité énergétique à l’échelle du réseau est abordé. Une nouvelle technique basée sur un algorithme de classification est alors proposé. Cette dernière permet d’améliorer la fiabilité de la détection, notamment par sa capacité à rejeter du processus de décision les noeuds qualifiés de défectueux ou moins fiables
In this thesis we investigate the required efficiency and reliability trade-off of spectrum sensing techniques in cognitive wireless sensor networks (CWSNs). An overview of the developed spectrum sensing techniques in the literature is provided. Then, considering the challenges posed by the framework of resource-constrained nodes in CWSNs, we propose several improved local and cooperative methods for spectrum sensing. Firstly, in order to minimize the channel observation duration and to get reduced power consumption, the problem of running the spectrum sensing process from a small sample size is addressed. We thus propose two techniques in order to increase the strength of the decision on the presence or not of a signal: local spectrum sensing based on the goodness-of-fit (GoF) principle and cooperative spectrum sensing based on the Dempster- Shafer (D-S) theory of evidence. Moreover, considering the energy efficiency of the whole network and the reliability of the decision, a robust and energy efficient cooperative spectrum sensing scheme is proposed. This latter is based on a clustering algorithm and utilizes a double reliability evaluation. Compared with the methods in the literature, the proposed method present an improved performance of detection, and is designed to support harsh channel conditions and faulty nodes

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37

Walsh, E. "Exploring the cognitive precursors of movement using a sensory-detection task". Thesis, University College London (University of London), 2008. http://discovery.ucl.ac.uk/1446183/.

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Movement-related sensory suppression is an example of a motor-sensory interaction whereby sensory stimuli are perceived as less intense before and during a movement than at rest. This thesis focuses on sensory suppression of a weak electrocutaneous stimulus delivered just prior to movement onset, and develops this situation as a paradigm for studying motor-sensory interactions. In a typical experiment, subjects prepared a motor response in advance of a visual signal. They received a weak electric shock to the right hand just prior to voluntary movement. Subjects reported at the end of each trial whether they detected the shock or not. Movement-related sensory suppression was measured by comparing shock detection rates with non-movement control trials. This general paradigm was then used in a series of behavioural experiments which systematically manipulated cognitive processing prior to movement. Premovement suppression was used to investigate the cognitive precursors of movement. First, it was shown that sensory suppression occurred for actions which were prepared, but then inhibited before execution. Second, sensory suppression was combined with the classic "stop-signal" paradigm. On trials where a stop signal came too late for subjects to inhibit their movement, a brief period of release from sensory suppression was nevertheless observed, as if the movement had been cancelled. This brief independence of sensory and motor systems suggests that the balance of excitation-inhibition is set separately for each system. Third, when subjects performed pre-prepared sequences of movements, premovement sensory suppression was related only to the first movement in the sequence, and not to subsequent movements. This suggests that motor-sensory interactions are programmed at the level of individual movements, not sequences. Finally, delivery of an unexpected startling auditory stimulus produced an acceleration of sensory suppression corresponding to the well-known acceleration of motor reaction time. This finding suggests that subcortical motor circuits involved in startle may also contribute to sensory suppression. Overall, sensory suppression proved a useful tool for investigating the cognitive processes that take place prior to movement.

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38

Sciarini, Lee William. "Noninvasive physiological measures and workload transitions an investigation of thresholds using multiple synchronized sensors /". Orlando, Fla. : University of Central Florida, 2009. http://purl.fcla.edu/fcla/etd/CFE0002781.

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39

Ludowici, Charles John Henry. "Temporal Selection in Dynamic Displays: Sensory Information Persists Despite Masking". Thesis, The University of Sydney, 2019. https://hdl.handle.net/2123/22069.

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The visual system receives a dynamic stream of information, but it has a limited capacity and must deploy its resources to behaviourally relevant stimuli - a process referred to as “attention”. Rapid serial visual presentation (RSVP) is an experimental method for investigating attention’s time course by presenting a rapid sequence of stimuli at a single location. Attentional selection in both naturalistic viewing and RSVP is limited by masking, and many models of selection in RSVP assume that masking terminates sensory memory for stimuli that are no longer present. However, there is indirect evidence that information about unselected RSVP stimuli may persist in a buffer despite masking. In this thesis we directly investigate buffering and selection of a cued item from one of multiple simultaneous RSVP streams. We use mixture modelling to analyse reports from only those trials in which participants identified a letter in response to the cue, and outline a novel quantitative test for buffering (Chapter 2). This provides new insights into the temporal variability of selection with exogenous and endogenous cues (Chapter 3). A series of experiments show that participants can select buffered representations, despite masking, and this appears to be related to the number of simultaneous RSVP streams (Chapter 4). We also investigate possible contributions of crowding and eccentricity to selection (Chapter 5). RSVP provides a measure of attention’s timing that replicates classic attentional effects. However, participants appear to dedicate attention to the streams prior to the cue’s appearance. When there are few streams, this leads to attentional speeds fast enough to select a stimulus representation that persists briefly, despite the masking inherent in RSVP. This falsifies theoretical claims about masking in RSVP, and demonstrates that the dynamic nature of naturalistic viewing does not prevent selection from sensory memory.

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40

Cahn, Baruch Rael. "Neurophysiologic correlates to sensory and cognitive processing in altered states of consciousness". Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2007. http://wwwlib.umi.com/cr/ucsd/fullcit?p3258980.

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Thesis (Ph. D.)--University of California, San Diego, 2007.
Title from first page of PDF file (viewed June 13, 2007). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 260-296).

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Sivonen, Päivi Helena. "Event related brain activation in speech perception: from sensory to cognitive processes /". Leipzig : MPI for Human Cognitive and Brain Sciences, 2006. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=015683097&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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42

Roy, Jefferson Edward. "Signal processing by vestibular nuclei neurons : dissociating sensory, motor, and cognitive influences". Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84430.

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The vestibular sensory apparatus and associated vestibular nuclei are generally thought to encode angular head velocity during our daily activities. However, in addition to direct inputs from vestibular afferents, the vestibular nuclei receive substantial projections from cortical, cerebellar, and other brainstem structures. Given this diversity of inputs we asked: how are the responses of vestibular nuclei neurons to head velocity modified by these additional inputs during naturally occurring behaviours? Here we have focused on three specific classes of neurons in the vestibular nuclei: (1) vestibular-only (VO) neurons which are thought to mediate, at least in part, the vestibulocollic reflex (VCR); (2) position-vestibular-pause (PVP) neurons which mediate the vestibuloocular reflex (VOR), and; (3) eye-head (EH) neurons, which are thought to mediate pursuit eye movements.
We first characterized neuronal responses to passive rotation in the head-restrained condition, and then released the head to record the discharges of the same neurons during self-generated head movements. VCR interneurons (VO neurons) faithfully transmitted head velocity signals during passive head motion, but their responses were greatly attenuated during all behaviours during which the monkey's behavioral goal was to move its head relative to the body. Moreover, the attenuation occurs only when neck proprioceptive inputs match those predicted by the neck motor command. We propose that the sensory-motor matching is meditated by interconnections with the cerebellum. Our findings indicate that the VCR is suppressed during active head movements, but remains responsive to unexpected head perturbations. In contrast, VOR interneurons (PVP neurons) faithfully transmitted head velocity signals when the animal stabilized its gaze, regardless of whether the head motion was actively or passively generated; their responses were attenuated only when the monkey's behavioral goal was to redirect its axis of gaze relative to space. We propose that efference copies of oculomotor/gaze commands are responsible for the behaviourally dependent modulation of PVP neurons (and by extension the VOR) during gaze redirection. Finally, the activity of EH neurons was recorded during head-restrained smooth pursuit and eye-head gaze pursuit. EH neurons were not influenced by error terms and their activity was best described by an eye movement-based model. In addition, during gaze pursuit EH neurons were found to encode gaze and head movement-related signals. Furthermore, neuron responses could be predicted by their head movement sensitivity during passive whole-body rotation in the dark and gaze movement sensitivity during smooth pursuit, regardless of the stimulation condition. We propose that EH neuron responses reflect the summation of head movement information fro

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43

Demery, Zoe P. "Comparative sensory & cognitive adaptations for exploratory learning in parrots & humans". Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4526/.

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How do different animals cope with the vast environmental complexity they face from birth or hatching? If animals’ genes have not provided the necessary information, then exploration is essential for gathering information and learning about the surrounding world. Much of cognition research to date has focussed on what the different abilities of different animal species are, rather than how they actually process information. This thesis has taken a distinctive interdisciplinary approach to tackle this problem from different angles: asking how the senses, environment and different behavioural strategies influence exploratory learning – specifically in the naturally exploratory parrot and human child. It investigated parrots’ visual fields and their tactile ‘bill tip organ’ to describe the limits of their sensorimotor exploration, both in approach to and during manipulation of an object. A series of increasingly complex behavioural tasks were also conducted with parrots and children, involving different novel objects and causal problems. This project has given us insight into how we and other animals structure information in different situations. It has the potential to expand the understanding of a wide range of fields, such as in aiding how human developmental disorders may be treated, or by informing robotics design.

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Beam, Christina Ashley. "Effects of Sensory and Cognitive Vigilance Tasks on Cerebral Blood Flow Velocity". University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1036017621.

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45

Emerson, Carol S. "Sensory and cognitive processing deficits in anxious depressed children : a neurobehavioral study /". Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-09192008-063149/.

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46

Landry, Mathieu. "Combining attention: A novel way of examining the links between sensory processing, attention, and behavior". Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=119703.

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Many everyday tasks, like asking for directions, require our attentional systems to combine the information coming from the senses with our current intentions. This intuitive notion suggests that combining attention might reflect a fundamentally novel way in which attention supports complex behavior and in turn affects perceptual processing of attended events. Using established paradigms we demonstrate for the first time that joint recruitment of multiple attentional systems leads to corresponding combined increases in behavior and sensory processing. This result not only provides a new conceptual framework for characterizing the role of attention in behavior but it also suggest an important role of combined attention in maintaining atypical behaviors (e.g., addiction and/or behavioral disorders) which may critically involve combining perceived meaning of the incoming sensory stimuli with individual goals.
Certaines tâches de notre quotidien, comme demander à quelqu'un de nous indiquer les directions pour rejoindre un lieu, requièrent que les systèmes attentionnels combinent les informations sensorielle et intentionnelle. Cette façon intuitive de conceptualiser l'attention suggère que la combinaison de systèmes attentionnelles pourrait refléter une nouvelle approche dans notre compréhension sur la façon dont l'attention permet l'émergence de comportements complexes et affecte le traitement de l'information perceptuelle. Utilisant un paradigme de recherche établi, nous démontrons pour la première fois que le recrutement conjoint de multiples systèmes attentionnelles mène à un accroissement équivalent sur le plan des performances comportementales et du traitement de l'information sensorielle. Non seulement ce résultat fournit-il un nouveau cadre conceptuel caractérisant le rôle primordial de l'attention dans l'accomplissement de divers comportements, mais il suggère également que l'attention combinée pourrait représenter un élément important dans le maintient de comportements atypiques (p.ex., dépendances et/ou troubles comportementaux) reflétant la combinaison du traitement de la signification des événements perçus en lien avec les buts individuels.

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Hughson, Angus. "Cork and talk the cognitive and perceptual bases of wine expertise /". Connect to full text, 2003. http://hdl.handle.net/2123/490.

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Thesis (Ph. D.)--University of Sydney, 2003.
Title from title screen (viewed Apr. 24, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Dept. of Psychology, Faculty of Science. Includes bibliography. Also available in print form.

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Mian, Omer. "Intelligent Spectrum Sensor Radio". Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1215360432.

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49

Garcia, Rodrigo I. S. M. Massachusetts Institute of Technology. "Cell-type specific contributions to Rett Syndrome : neuronal and astrocytic signaling and sensory processing". Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/106431.

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Thesis: Ph. D. in Neuroscience, Massachusetts Institute of Technology, Department of Brain and Cognitive Sciences, 2016.
Page 127 blank. Cataloged from PDF version of thesis.
Includes bibliographical references.
Loss of function mutations in the X-linked gene encoding for MeCP2 are the underlying genetic cause for Rett Syndrome (RTT), a devastating neurodevelopmental disorder that primarily affects girls. While the function of this transcriptional regulator remains elusive and complex, recent focus has turned to downstream signaling pathways as putative targets for novel therapeutics. The complexity of MeCP2 function is compounded by the heterogeneity of cell types in the brain, with recent evidence implicating glia cells in RTT pathophysiology. The focus of my thesis has been two-fold: exploring signaling mechanisms downstream of MeCP2 and the potential of IGF-1 as a therapeutic for RTT, and examining functional astrocyte sensory processing in healthy and impaired circuits. I present evidence that IGF-1 levels are reduced in mouse models of RTT and systemic treatment with IGF-1 leads to improvements in lifespan, respiratory patterns, and social behaviors. These effects are accompanied by increased synaptic proteins, activation of signaling pathways, and enhanced excitatory transmission, as well as effects on plasticity in visual cortex circuits. Astrocytes, known to contribute to synapse formation and maintenance, have been implicated alongside neurons as contributors to the RTT phenotype. They express the two most abundant glutamate transporters in the brain responsible for the majority of glutamate clearance from synapses. Indeed, lack of MeCP2 in astrocytes leads to a reduction in signaling pathways and aberrant glutamate transporter expression, with strong implications for synaptic and circuit activity. Efficient processing of visual information requires processing salient features while overcoming the inherent variability in neuronal networks. Natural movies evoke reliable responses from pyramidal neurons in visual cortex and my work reveals that discrete microdomain regions of visual cortex astrocytes also exhibit temporally reliable and spatially correlated responses to natural scenes. I show that glutamate transporters, which influence astrocytic Ca 2 signaling and synaptic transmission, regulate the reliability of astrocyte microdomain responses and thus contribute crucially to visual information processing. Finally, I show that in a RTT mouse model, astrocyte microdomains elicited by visual stimuli are reduced in size, consistent with the reduced synaptic transmission and neuronal responses observed in these mice.
by Rodrigo I. Garcia.
Ph. D. in Neuroscience

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50

Robins, Rebecca. "Sensory and cognitive influences on oculomotor and whole-body coordination during standing turns". Thesis, Liverpool John Moores University, 2015. http://researchonline.ljmu.ac.uk/4415/.

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It is well-established that turning on the spot or changing the direction of walking involves a stereotyped sequence of eye, head and body segment rotation characterized by an anticipatory gaze strategy driven primarily by eye movements (nystagmus). However, the relationship between eye movements and whole-body coordination during turning has not been fully explored under different environmental and sensory contexts and as a result, the neural mechanisms responsible for this coordination are poorly understood. The first aim of this thesis was to investigate the effects of turn size and speed on eye movements and intersegmental coordination. Results showed systematic relationships between turn speed, amplitude and eye and whole-body coordination characteristics and that the timing of eye, head and axial segment reorientation onset does not accurately represent coordination during the turn. Secondly, we investigated the effects of either removing vision or suppressing eye movements during turns. We found that eye and motor behaviour during vision removal was similar to behaviour during full vision, however suppressing eye movements delayed gait initiation and decreased stepping frequency throughout the turn. Next we examined the influence of neck muscle vibration on turning and found that stimulating neck proprioceptors to evoke the CNS perception of head rotation with respect to the upper body resulted in early turn initiation. Lastly, we looked at the effects of divided attention using a secondary cognitive task during the turn. We found that turn onset was delayed during dual-tasking, but eye and body coordination were unaffected. We conclude that oculomotor nystagmus during turning represents a crucial component of an automatic, subcortically generated motor synergy, the release of which is dependent on cortical and sensory input (i.e. eye and neck proprioception). We propose that turning on-the-spot is organized centrally as part of a whole-body gaze shift rather than a specialized adaptation to conventional locomotion.

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Tesi sul tema "Sensory cognition"

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