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The classic distinction between the body schema and the body image received renewed interest in cognitive psychology, in part because of the attempts by the leading psychologist Charles Spence and his co-authors to synthesise a mounting body of research into the multisensory nature and functional properties of the neural structures in primate cortex that are sensitive and responsive to cross-modal stimuli generated from the body and objects located close to the body, and the famous rubber hand illusion which purported to illustrate how the perception and understanding of what counts as one’s body, i.e., our body image, can be manipulated to include foreign, body-part-like, objects such as a rubber hand. This approach was intended to settle age old questions about how the body schema – the system sub-personal sensorimotor system that shapes, facilitates and regulates motor control – is implemented in the brain and address historic confusions about how the body schema should be understood as an explanatory concept, as well as the problems surrounding the body schema and image distinction on the grounds of the persistent conflation between the two concepts. However, after offering several proposals as to how the body schema should be used to organise and interpret the empirical data, the distinction fell out of favour with Spence and his colleagues on the grounds of the very problems they intended to resolve. The proposed solution is an alternative theoretical framework that, I shall argue, never materialised. Instead, the various definitions they disseminate, I will claim, simply serve to further perpetuate the same problems and confusions about the body schema. Thus, the current state of the literature on the body image and schema in cognitive psychology is in dire need of a conceptual framework that would help us situate and interpret the important empirical data. I propose that we revisit the philosophical debates that were inspired by the philosopher Shaun Gallagher as part of his project to provide a conceptual analysis of the body schema and image distinction and vindicate its status as an important explanatory device for the explanatory ambitions of embodied cognition. Gallagher’s analysis opens up important questions about how the sub-personal multisensory processes of the body schema not only facilitate moment-by-moment motor behaviours, but how they shape and optimise motor control across developmental timelines, as well the importance of the embodied configuration of an agent and its particular eco-niche for shaping and facilitating its motor behaviours. The second important argument of the thesis is that the response to Gallagher’s analysis has simply served to suppress the line of research that Gallagher inspired because the questions his analysis raises have been overshadowed by more general disputes between Gallagher and his opponents about the shape an analysis of the body schema from the perspective of embodied cognition should take. As such, potentially promising lines of research in relation to the body schema have since dried up. As part of my attempt to make progress on the issues that are laid out at the first and second stages of the thesis, the third stage will involve an exploration into the seminal Bayesian approach to understanding cross-modal cue optimisation as it applies to object perception (Banks & Ernst, 2002) and the recent extension of this paradigm to the multimodal sensorimotor processes that underpin motor behaviour in action-oriented cognitive science (e.g., Friston, 2010). The conclusion of the thesis is that the move from an embodied to an action-oriented analysis of the body schema, and the conceptual distinction of which it is part, provides us with the right kind of theoretical resources to begin to pursue fruitful avenues of research that allow us to begin to address the questions set out by Gallagher’s analysis whilst avoiding (some of) the pitfalls that beset the embodied approach. In the final chapter I use this model of the body schema to illustrate how it can provide the basis for working back up towards a comprehensive theory of the body image and schema distinction, which I then bring to bear on current, as-yet-unaddressed, issues in developmental psychology.

Critical care nurses experience stressful situations in their daily working environments. The question arises for nurses: are there adequate support systems in the critical care environment and what are critical care nurses doing to mantain their own health and well-being. Facilitating conscious awareness among critical care nurses could enhance their resiliency and their hardiness, strengthening their coping capacities in stressful working situations. The contextual framework adopted for this research was the Neuman Systems Model. A qualitative research approach (exploratory, descriptive and contextual) was used to explore and describe the stress experienced by critical care nurses. Focus group interviews were conducted with critical care nurses and individual interviews with nurse managers. The results revealed their perceptions and experiences about the effects of stress in the critical care environment, as well as some of their coping strategies. Raising critical care nurses' levels of conscious awareness about their coping strategies with stressful events in their daily working lives, could enhance their resiliency and hardiness, enabling them to continue working effectively in stressful environments. This could enhance the general well-being of individual critical care nurses, the nursing care rendered to critically ill patients, and save money for the health care services by reducing turnover rates among critical care nurses. / Health Studies / D.Litt. et Phil. (Health Studies)

Critical care nurses experience stressful situations in their daily working environments. The question arises for nurses: are there adequate support systems in the critical care environment and what are critical care nurses doing to mantain their own health and well-being. Facilitating conscious awareness among critical care nurses could enhance their resiliency and their hardiness, strengthening their coping capacities in stressful working situations. The contextual framework adopted for this research was the Neuman Systems Model. A qualitative research approach (exploratory, descriptive and contextual) was used to explore and describe the stress experienced by critical care nurses. Focus group interviews were conducted with critical care nurses and individual interviews with nurse managers. The results revealed their perceptions and experiences about the effects of stress in the critical care environment, as well as some of their coping strategies. Raising critical care nurses' levels of conscious awareness about their coping strategies with stressful events in their daily working lives, could enhance their resiliency and hardiness, enabling them to continue working effectively in stressful environments. This could enhance the general well-being of individual critical care nurses, the nursing care rendered to critically ill patients, and save money for the health care services by reducing turnover rates among critical care nurses. / Health Studies / D.Litt. et Phil. (Health Studies)

La perception visuelle implique une interaction complexe entre les yeux, le cerveau et les processus cognitifs, transformant les stimuli visuels en une représentation interne de l'environnement. Bien qu'une fraction limitée des informations parviennent à notre conscience visuelle, le cerveau traite une quantité considérable d'informations de manière inconsciente. Des recherches en imagerie par résonance magnétique fonctionnelle (IRMf) ont visé à mieux discerner les corrélats neuronaux associés à la perception consciente et inconsciente. Cependant, l'identification précise des régions cérébrales impliquées dans la génération d'une perception consciente, et leur modulation par l'expérience ou par des lésions cérébrales, demeure un défi. Cette thèse examine le traitement conscient et inconscient de l'information visuelle à l'aide de tâches visuelles et de neuroimagerie, pour comprendre comment ces processus se reflètent dans l'activation cérébrale et l'impact de lésions du cortex visuel. L'article 1 vise à identifier de manière empirique les zones d'activation fonctionnelle associées au traitement visuel conscient et inconscient chez les individus neurotypiques, en menant deux méta-analyses quantitatives de données de neuroimagerie. Les résultats révèlent que le traitement conscient mobilise la jonction fronto-inférieure, le sillon intrapariétal, le cingulum antérieur dorsal, le gyrus angulaire, le cortex temporo-occipital et l'insula antérieure. Le traitement visuel inconscient sollicite davantage les régions postérieures, comme le complexe occipital latéral. L'article 2 traite des processus cognitifs associés à la modulation de l'activation fonctionnelle suite à une lésion du cortex visuel. La déficience visuelle cérébrale (DVC) est caractérisée par une perte des fonctions visuelles due à un dommage cérébral plutôt qu'à une atteinte des yeux. Bien que la majorité des individus ne regagnent pas une vision normale, dans certains cas fascinants une amélioration peut être notée avec le temps en raison de la capacité du cerveau à se réorganiser. La perte visuelle peut s'accompagner du blindsight, où les individus sont capables de traiter de l'information visuelle tout en niant l'avoir vue. Cet article novateur utilise un paradigme de détection de mouvement pour évaluer l'activation des structures corticales et sous-corticales lors d'une performance de blindsight chez un individu avec DVC. Cette contribution significative met en évidence des corrélats neuronaux indépendants des aires visuelles primaires, associés à des structures spécifiques pendant la détection de mouvement en blindsight. Le chapitre 4 présente une base de données d'IRM haute résolution pour la perception du mouvement visuel d'individus neurotypiques et atteints de DVC. Les données incluent des mesures d'IRM structurelles, fonctionnelles, et de diffusion, des évaluations comportementales et de suivi du regard, des mesures électrophysiologiques, en plus de données prétraitées, le code et des métriques de contrôle de la qualité. L'article 3 caractérise les conséquences neurologiques des lésions cérébrales chez les participants DVC, ainsi que l'impact sur leur capacité à traiter divers stimuli de mouvement, comparés à un groupe de contrôles neurotypiques, en utilisant des techniques comportementales et d'IRM fonctionnelle à haute résolution. La détection automatisée des lésions a permis de quantifier de manière fiable l'étendue des dommages cérébraux et les participants ont été catégorisés selon leur capacités visuelles résiduelles. Les résultats confirment que le cerveau peut traiter des informations visuelles malgré l'absence de zones visuelles primaires intactes. Les participants DVC ont présenté des altérations fonctionnelles étendues, contrairement aux participants neurotypiques, qui ont montré une activation focalisée dans des régions spécialisées pour le traitement visuel et de mouvement. L'hémisphère lésé présente une activation plus synergique dans l'aire temporale médiane et le complexe occipital latéral. Dans l'hémisphère intact, ce dernier peut répondre à une stimulation du champ visuel atteint. Le thalamus et le pulvinar ipsilésionnels ont montré une dominance ipsilatérale en réponse au mouvement, contrairement à la dominance controlatérale dans l'hémisphère intact et chez les participants DVC avec des capacités visuelles résiduelles comparables à celles des contrôles. Cette thèse, par une approche multimodale, étudie les mécanismes neuronaux du traitement visuel chez les individus neurotypiques et atteints de DVC. L'utilisation d'étapes empiriques séquentielles, notamment une étude de cas, des analyses de groupes et des méta-analyses, renforce la fiabilité et l'applicabilité de la recherche, et vise à cartographier l'adaptation cérébrale après une lésion du cortex visuel. / Visual perception involves the intricate interplay of the eyes, brain, and cognitive processes, enabling photons of visible light to be captured on the retina, processed through specific pathways in the brain and transformed into a rich internal representation of our surroundings. While only a fraction of information reaches conscious awareness, the brain can process the remaining unconsciously. Functional magnetic resonance imaging studies have sought to understand the neural signals associated with conscious versus unconscious perception. However, comprehensively understanding the core brain regions involved in generating a conscious perception and their modulation through experience or brain damage remains a challenge. In this thesis, we investigate the conscious and unconscious processing of visual information through a series of visual tasks. We aim to understand how these processes are reflected in brain activation and how they can be modulated by damage to the visual cortex. Article 1 aimed to empirically identify and characterize areas of reliable convergence in functional activation of regions engaged during either conscious or unconscious visual processing in neurotypical participants by conducting two distinct quantitative meta-analyses. The findings reveal that conscious visual processing readily engages a constellation of regions comprising the inferior frontal junction, intraparietal sulcus, dorsal anterior cingulate, angular gyrus, temporo-occipital cortex and anterior insula, whereas unconscious processing recruits posterior regions, mainly the lateral occipital complex. The aim of Article 2 was to provide a detailed understanding of cognitive constructs and functional alterations following visual cortex damage. Cerebral visual impairment (CVI) refers to a loss of visual function caused by damage to the brain rather than the eyes. While most individuals do not recover intact vision, some cases have demonstrated improvement over time due to the brain's ability to reorganize itself. In certain instances of visual loss, blindsight can occur, allowing individuals to process visual information without conscious awareness. To our knowledge, this article was the first to propose the use of an event-related motion detection paradigm to assess functional activation in cortical and subcortical structures, independant of primary visual areas, during a CVI individual's blindsight performance. Chapter 4 aimed to conceptualize and acquire a unique high-resolution MRI dataset for studying visual motion perception in neurotypical and CVI individuals. This comprehensive dataset encompasses multiple modalities, including structural, functional task-based, resting-state and diffusion MRI, behavioral and evaluations, electrophysiological measures, and eyetracking data, in addition to preprocessed data, code and quality control metrics. Article 3 aimed to understand the functional consequences of brain damage in CVI individuals and the resulting impact on their ability to process diverse visual motion stimuli, including looming and biological motion, compared to a group of neurotypical controls, using behavioral and high-resolution neuroimaging techniques. Automatic lesion mapping enabled to reliably quantify the extent of brain damage and participants were categorized based on their residual visual ability. The findings demonstrate that the brain can process and represent visual information, without intact primary visual areas. CVI participants exhibited broad functional alterations, contrasting the focused activation in visual and motion processing regions for neurotypical controls. Specifically, the lesioned hemisphere displayed synergistic activation in the middle temporal area and lateral occipital complex, while the intact hemisphere's lateral occipital complex responded to impaired visual field stimulation. The ipsilesional thalamus and pulvinar demonstrated an ipsilateral dominance in response to looming motion, in contrast to the contralateral dominance in the intact hemisphere and among CVI participants with residual visual abilities akin to neurotypical controls. By employing a multi-modal approach integrating behavioral assessments, structural and functional neuroimaging methods, this thesis comprehensively investigates the neural mechanisms underlying visual processing in both neurotypical individuals and those with CVI. The use of sequential steps in empirical science, namely a case study, group analyses, and meta-analyses, enhances the reliability and applicability of the research, and effectively contributes to help map brain adaptation post visual cortex injury and further inform neurotypical visual information processing.