Sökning: "visual cortex"

Visar resultat 6 - 10 av 65 avhandlingar innehållade orden visual cortex.

  1. 6. Diffusion Tensor Imaging and Tractography of the Visual Pathways

    Författare :Ylva Lilja; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Diffusion tensor imaging; Visual pathways; Tractography; Temporal lobe resection; Pituitary adenomas;

    Sammanfattning : The visual pathways are essential for human vision, stretching from the retinas of the eyes, via the anterior visual pathways and the optic radiations, to the primary visual cortex in the occipital lobe. Injury to these structures will lead to visual impairment – from small deficits to blindness. LÄS MER

  3. 7. Neural limits of visual resolution

    Författare :Zoran Popovic; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; cell separation; cortical magnification; detection; estimated receptive field; high-pass filtered optotypes; nyquist limit; psychophysics; resolution; ganglion cells;

    Sammanfattning : Aims: The aim of this thesis was to formulate a model of retinal neural circuitry in humans based on morphological estimates of retinal cone and ganglion cell populations, to compare results based on this model to psychophysical measurements of visual resolution and identify the retinal neural factors that limit visual resolution.Materials & Methods: Total displacement of central ganglion cells from foveal cones was obtained by estimating the length of fibers of Henle in four human retinas along the nasal or vertical hemi-meridians. LÄS MER

  4. 8. The conscious brain : Empirical investigations of the neural correlates of perceptual awareness

    Författare :Johan Eriksson; Lars Nyberg; Geraint Rees; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; consciousness; visual perception; object identification; functional neuroimaging; top-down processing; prefrontal cortex; auditory perception; Neuroscience; Neurovetenskap;

    Sammanfattning : Although consciousness has been studied since ancient time, how the brain implements consciousness is still considered a great mystery by most. This thesis investigates the neural correlates of consciousness by measuring brain activity with functional magnetic resonance imaging (fMRI) while specific contents of consciousness are defined and maintained in various experimental settings. LÄS MER

  5. 9. Biologically-Based Interactive Neural Network Models for Visual Attention and Object Recognition

    Författare :Mohammad Saifullah; Arne Jönsson; Christian Balkenius; Anders Lansner; Linköpings universitet; []
    Nyckelord :Biologically-Based Models; Object Recognition; Visual Attention; Interactive Neural Network; Occlusion; Overlapping;

    Sammanfattning : The main focus of this thesis is to develop biologically-based computational models for object recognition. A series of models for attention and object recognition were developed in the order of increasing functionality and complexity. LÄS MER

  7. 10. Variations in Functional Lateralization

    Författare :Peter E Wendt; Institutionen för psykologi; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; posterior association cortex; prefrontal; DLPFC; regional cerebral blood flow; normal subjects; lateralization; asymmetry; performance; creativity; Neurology; neuropsychology; neurophysiology; cognitive; ethanol; activation; visual stimulation; functional; verbal; divergent; spatial; Neurologi; neurofysiologi; neuropsykologi;

    Sammanfattning : The general aim of this thesis was to study asymmetric activation of the neocortex in normal subjects, using the rCBF technique and different cognitive tasks. The aim was also to study individual and group variations of asymmetric activation, as well as factors pertaining to these variations. The thesis is based on four investigations. LÄS MER