598 research outputs found

    Cerebral Metamorphopsia: Perceived spatial distortion from lesions of the adult human central visual pathway

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    Metamorphopsia is the perceived visual illusion of spatial distortion. Cerebral causes of metamorphopsia are much less common than retinal or ocular causes. Cerebral metamorphopsia can be caused by lesions along the central visual pathway or as a manifestation of epileptogenic discharges. Geometric visual distortions may result from structural lesions of the central visual pathway after reorganisation of the retinotopic representation in the cortex. Very few experimental investigations have been performed regarding cerebral metamorphopsia as it is often viewed as a clinical curiousity and analysis of the perceived distortion is difficult due to its subjective nature. Investigations have been undertaken to understand cortical plasticity as an explanation for visual filling-in. There has been much interest in cortical reorganisation after injuries to the peripheral and central visual pathway. Behavioural experiments aimed at quantifying the possible visual spatial distortion surrounding homonymous paracentral scotomas may be able to demonstrate cortical reorganisation after brain-damage and provide clues regarding the neural processes of visual perception. The aims of the thesis are: 1. To identify which cases of metamorphopsia, both published and unpublished, might be a consequence of cortical spatial reorganisation of retinotopic projections. 2. To investigate perceptual spatial distortion surrounding homonymous paracentral scotomas in adults with isolated unilateral injuries of the striate cortex. A review of the literature describing cases of cerebral metamorphopsia was performed. Metamorphopsia caused by retinal or ocular pathology, psychiatric conditions, drugs or medications were excluded. A retrospective case series of eight patients with metamorphopsia from a cerebral cause was performed in two clinical neurology practices specialising in vision disorders. Two cases who suffered from paracentral homonymous scotomas due to isolated unilateral primary visual cortex (V1) lesions were identified from a Neuro-ophthalmology practice. Neuropsychophysical experiments to investigate visual spatial perception surrounding their scotomas were developed and tested using MATLAB and Psychtoolbox. The use of the term 'metamorphopsia' was only in reference to cases in which contours or lines were experienced as distorted. In the published literature, few cases of cerebral metamorphopsia have been identified as being potentially due to cortical reorganisation. The main result is a statistically significant visual spatial distortion in the visual field surrounding a paracentral homonymous scotoma when compared to a normal control. There is also significant distortion of perception in the subjects' "unaffected" visual hemifield. After lesions of V1, visual perceptual spatial distortions may occur in the visual field surrounding homonymous paracentral scotomas. The spatial distortion may also occur in the normal hemifield possibly due to long-range cortical connections crossing to the other hemisphere through the corpus callosum. A collaborative approach across disciplines within vision science is required to further investigate the mechanisms responsible for perceptual visual illusions. Behavioural testing in brain-damaged cases remains important in developing theories of normal visual processing. New neuroimaging and neuroscience techniques could then test these theories, furthering our understanding of visual perception. An understanding of normal visual perception could allow future modification of neuronal processes to harness cortical reorganisation and potentially restore functional vision in humans with lesions of the central visual pathway

    Examining the Relationships Between Distance Education Students’ Self-Efficacy and Their Achievement

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    This study aimed to examine the relationships between students’ self-efficacy (SSE) and students’ achievement (SA) in distance education. The instruments were administered to 100 undergraduate students in a distance university who work as migrant workers in Taiwan to gather data, while their SA scores were obtained from the university. The semi-structured interviews for 8 participants consisted of questions that showed the specific conditions of SSE and SA. The findings of this study were reported as follows: There was a significantly positive correlation between targeted SSE (overall scales and general self-efficacy) and SA. Targeted students' self-efficacy effectively predicted their achievement; besides, general self- efficacy had the most significant influence. In the qualitative findings, four themes were extracted for those students with lower self-efficacy but higher achievement—physical and emotional condition, teaching and learning strategy, positive social interaction, and intrinsic motivation. Moreover, three themes were extracted for those students with moderate or higher self-efficacy but lower achievement—more time for leisure (not hard-working), less social interaction, and external excuses. Providing effective learning environments, social interactions, and teaching and learning strategies are suggested in distance education

    2023- The Twenty-seventh Annual Symposium of Student Scholars

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    The full program book from the Twenty-seventh Annual Symposium of Student Scholars, held on April 18-21, 2023. Includes abstracts from the presentations and posters.https://digitalcommons.kennesaw.edu/sssprograms/1027/thumbnail.jp

    2023-2024 Lindenwood University Undergraduate Course Catalog

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    Lindenwood University Undergraduate Course Catalog.https://digitalcommons.lindenwood.edu/catalogs/1209/thumbnail.jp

    Unpacking Creativity for Language Teaching

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    Before unlocking creativity, we must first unpack what it means. In this book, creativity is unravelled from various perspectives and the relevance for language teaching and learning is explored. Tin offers a coherent discussion of creativity, adopting an inclusive and integrated but, at the same time, focused approach to creativity. Divided into 12 chapters, the book covers: • A critical review of the way the term ‘creativity’ is used, defined and written about in various disciplines • Various models and theories of creativity, the product- and process-oriented views of creativity and their relevance for language teaching • Three pillars on which creative language pedagogy should be based • Over 60 practical tasks, applying theoretical arguments and principles of creativity to language teaching and learning. Based on the author’s own practice and research on creativity over the last two decades, the book provides exciting new ideas for scholars and practitioners interested in creativity and creative language pedagogy. The book serves as an important contribution for students, teachers and scholars in the field of applied linguistics, language teaching and education

    Towards fast and robust authentication schemes in Body Area Networks

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    The emergence of Body Area Networks (BANs) has paved the way for real-time sensing of human biometrics in addition to remote control of smart medical devices, which in turn is beginning to revolutionise the smart healthcare industry. However, due to their limited power and computational capabilities they are vulnerable to myriad of security attacks, thus securing BANs is paramount to their success and wider adoption in the medical and nonmedical domain. Achieving the desired security level for BANs while adhering to their strict constraints imposed by the limited resources available is an ongoing challenge. Solving such a challenge will be the focus of my thesis. In particular, my thesis will develop a novel, fast and robust authentication mechanisms amongst BAN devices while exploring new potential vulnerabilities that may threaten the existing approaches. To accomplish this goal the thesis provides a review of the state-of-the-art literature exploring authentication protocols that focus on biometrics, physical channel characters or other approaches, before proceeding to introduce three novel works. Firstly, identifying a concerning vulnerability within existing Electrocardiogram (ECG) based schemes, secondly, a solution to mitigate this exploit and finally a strategy which aims to reduce the time taken to complete the authentication process

    Investigation Into the Physical Environmental Correlates of Aggressive Behaviour in Children with Neurodevelopmental Disorders (NDDs)

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    Background: Physical environmental influences on childhood aggression in children with neurodevelopmental disabilities is a severely under-researched research locus. The aim of this doctorate was to elucidate specific associations between children’s developmental environment and aggressive behaviours, using this evidence to reciprocally inform an experimental psychology project to investigate underlying mechanisms. To explore these effects, the programme of study was broadly divided into three reflexive workstreams using diverse research methodologies. Methods: In the first workstream, I conducted a systematic review of the current literature examining physical environmental influences on childhood aggressive behaviours in both typically developing children (aged 0 – 18) and those diagnosed with NDDs. The literature on children with NDDs was substantially limited in comparison to peers without NDDs. The second workstream was comprised of a large-scale secondary data analysis (multiply imputed growth curve modelling) to investigate environmental influences on conduct problems across early development. I used data from the Millennium Cohort Study (MCS) to assess how physical environmental metrics, such as neighbourhood greenspace, air pollution, household crowding, and presence of home damp influenced the development and severity of conduct problems in children with (n=8013) and without NDDs (n=155) between the ages of 3 – 11 years. Finally, building upon evidence from the previous two workstreams, I designed a proof-of-principle psychological experiment to examine the influence of urban nature exposure on children with NDDs. Specifically, simulating a real-world urban greenspace using a Person-Environment-Activity Research Laboratory (PEARL). This facilitated the ability to manipulate and isolate individual environmental aspects of urban nature exposure (light, sound, and projection). Following ethical review and approval, I recruited 3 children (100% male) with mild and moderate intellectual disability aged between 12 – 15 years (Mean age = 14) attending a local school for children with special educational needs. We examined their physiological reactions to four simulated urban green space aspects (light, sound, landscape projections, and vegetation) against a baseline control condition. I also collected demographic information on parent reported aggressive behaviours, exposure to local greenspace(s), physical and mental health history, medication, and adaptive behaviours (ABAS-3). This research lays the foundation for future large scale experimental paradigms that can disentangle the effects of nature exposure in these children, with the aim of translating these findings into real world therapeutic design interventions and relevant policy changes to improve the quality of the built environment for these children. Findings: From articles retrieved from my systematic review I found evidence for the beneficial influences of nature in both populations, and simultaneously negative effects of both noise and air pollution in typically developing children only. Evidence for other environmental aspects such as crowding, music, urbanicity, meteorology, and interior design had either insufficient or inconsistent evidence to extrapolate concreate conclusions. More evidence on the effect of these exposures on child aggression outcomes is recommended. From the analysis of the MCS cohort I found various sociodemographic factors (ethnicity, sex, poverty, family structure, maternal distress) and internal residential conditions were associated with increased childhood conduct problem trajectories in both groups of children. I also discovered potential evidence of a moderating influence effect of intellectual disability on the relationship between spatial density and conduct problems. From the final experimental project, I report preliminary evidence for the influence of urban greenspaces to reduce physiological arousal in children with complex neurodisability profiles. Initial evidence for the hierarchical nature of urban greenspace sensorial aspects was reported, for example: that urban nature soundscapes maybe a more influential environmental stimuli than lighting or landscape projections. Conclusion: Drawing together multi-disciplinary research methodologies facilitated the ability to identify disparities in research examining physical environmental determinants of aggression in neurodiverse child populations. Reciprocally, the systematic review and secondary data analysis contributed incrementally to filling this lacuna of research. Using findings from these two work streams, I identified that exploring the potentially therapeutic influences of urban nature exposure on children with neurodevelopmental disorders may provide novel indicators of its aetiological mechanisms. I reported original findings supporting these research aims, elucidating the potential hierarchical nature of urban greenspace elements. This was also the first study of its kind reporting the potential for simulated urban park spaces to reduce physiological arousal in neurodivergent children with aggressive behavioural difficulties

    2023-2024 Boise State University Undergraduate Catalog

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    This catalog is primarily for and directed at students. However, it serves many audiences, such as high school counselors, academic advisors, and the public. In this catalog you will find an overview of Boise State University and information on admission, registration, grades, tuition and fees, financial aid, housing, student services, and other important policies and procedures. However, most of this catalog is devoted to describing the various programs and courses offered at Boise State

    Cultivate Quantitative Magnetic Resonance Imaging Methods to Measure Markers of Health and Translate to Large Scale Cohort Studies

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    Magnetic Resonance Imaging (MRI) is an indispensable tool in healthcare and research, with a growing demand for its services. The appeal of MRI stems from its non-ionizing radiation nature, ability to generate high-resolution images of internal organs and structures without invasive procedures, and capacity to provide quantitative assessments of tissue properties such as ectopic fat, body composition, and organ volume. All without long term side effects. Nine published papers are submitted which show the cultivation of quantitative measures of ectopic fat within the liver and pancreas using MRI, and the process of validating whole-body composition and organ volume measurements. All these techniques have been translated into large-scale studies to improve health measurements in large population cohorts. Translating this work into large-scale studies, including the use of artificial intelligence, is included. Additionally, an evaluation accompanies these published studies, appraising the evolution of these quantitative MRI techniques from the conception to their application in large cohort studies. Finally, this appraisal provides a summary of future work on crowdsourcing of ground truth training data to facilitate its use in wider applications of artificial intelligence.In conclusion, this body of work presents a portfolio of evidence to fulfil the requirements of a PhD by published works at the University of Salford

    Screening people with diabetes for atrial fibrillation

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    Thesis by alternative route comprising four independent yet related studies exploring the relationship between diabetes and atrial fibrillation and whether screening people with diabetes for this common heart rhythm disorder, would be valuable. A systematic review critiques the utility, effectiveness and feasibility of the AliveCor screening application, demonstrating this as a valid and effective tool for this purpose. A screening study then demonstrates a higher prevalence of atrial fibrillation in people with diabetes, also showing statistical significance that increasing age, is a predictor for developing atrial fibrillation in this population. Another study then considers the quality of life study in people with atrial fibrillation and then people with atrial fibrillation and diabetes, showing the quality of life to be poorer in the majority of assessed domains, when both conditions coexist. Lastly, a qualitative interview study considers the views and experiences of people screened in the earlier study, demonstrating variable understanding around atrial fibrillation and views around how, when and who to screen
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