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Abstract
There is lack of agreement concerning many velocity-amplitude characteristics of saccadic eye movements. We analyzed, in 15 normal subjects, factors such as abduction, adduction, centering, eccentric, and across-the-center refixations to determine their possible influence upon peak velocity (PV) for 5°, 10°, 20°, and 30° movements. There was considerable intra- and intersubject variability in PV at each amplitude. Analysis of variance revealed no statistically significant difference among the various types of saccades except for the average PV of adduction refixations which was significantly greater at the 30° amplitude. Comparison of conventional 25 Hz. baiulwidth direct current electro-oculography (EOG) and 100 Hz. bandwidth infrared reflection showed higher values with the latter technique. We obtained normative data on saccadic velocity which permits definition of "pathologic slowness." The lower limits of normal mean PV for saccades of 5°, 10°, 20°, and 30° are 114, 167, 188, and 200° per second for conventional EOG and 145, 196, 213, and 227° per second for infrared reflection. Any mean PV which falls below these values should be considered abnormal.