Visual System Flashcards
Genetic origin of all animal eyes
Pax-6
Myopia
Cannot bring distant objects into clear focus due to focal pint of light falling short of retina
Hyperopia
Cannot focus on nearby objects due to focal point falling beyond retina
Rods
Light receptors in periphery of eye
Cones
Color receptors (blue, green, red) concentrated in the fovea
Magnocellular Ganglion Cells
Large ganglion cells in the eye that process black and white light
Parvocellular Ganglion Cells
Small ganglion cells in the eye that process color
Geniculostriate System
Lateral geniculate nucleus, V1, other visual areas; contains both black and white and color processing systems
Dorsal stream
Action, unconscious vision, m-system (depth, coarse)
Damage to dorsal stream results in…
Optic ataxia (problem with visually guided movements)
Ventral stream
Perception, conscious vision, p-system (color and detail)
Damage to ventral stream leads to…
Optic agnosia (impaired recognition)
Hemianopia
Stroke in one hemisphere leading to blind spot in opposite visual field
Quadrantanopia
Blind spot in upper quadrant due to stroke below clacarine fissure
Scotoma
Small blind spot in upper field of vision due to stroke below clacarine fissure
