NROC64H3 Lecture Notes - Lecture 3: Homonymous Hemianopsia, Hemianopsia, Quadrantanopia
Document Summary
Neurons in visual system: neural processing resulting in perception. Parallel pathway serving conscious visual perception originate in retina: progress to lgn, 1ary vc & higher order visual areas in temporal and parietal lobes. Neuronal receptive fields: sensitive to different facets of visual input. Map of visual field onto target structure (retina, lgn, s. colliculus, Striate cortex) overrepresentation of central visual field. Discrete point of light = activate many cells in target structure, overlapping rfs. Perception: based on brain"s interpretation of distributed patterns of activity; nobody reads this. Spiny stellate cells: spine-covered dendrites; layer ivc. Pyramidal cells: spines; thick apical dendrite; basal dendrites. Inhibitory neurons: lack spines; all cortical layers, forms local connections. Magnocellular lgn neurons: project to layer ivca ivb. Parvocellular lgn neurons: project to to layer ivcb iii. Koniocellular lgn axons: bypasses layer iv synapse in layer ii & iii. Ocular dominance columns and orientation columns: looks like.