| Description |
In this series, the purpose and nomenclature of eye movements are described, with the anatomical pathways generating and controlling the cortically-driven movements -- saccades and smooth pursuit in horizontal gaze, upgaze and downgaze -- discussed in detail. The importance of each of the three saccadic generators in the cortex, and of the cortical regions necessary for pursuit is identified. The pathology of these pathways is summarized, providing evidence of their clinical relevance. These pathological states include low-gain pursuit, slow-to-no saccade syndrome among others. Video clips of patients are used for visual demonstration of particular eye movement abnormalities, specifically those that result from a cerebral hemispherectomy, frontal lobe lesion, from progressive supranuclear palsy (PSP), and from central nervous system whipples disease. KEY WORDS: saccades, smooth pursuit, cerebral control of eye movements, gaze, frontal eye fields, medial superior temporal area, medial temporal visual area, extra-striate visual areas, visual stimulation of eye movement, optokinetic nystagmus, gain, low-gain pursuit, slow-to-no saccade syndrome, progressive supranuclear palsy, CNS whipples |
