[Study on human eye movements induced by blinks--report 1. Three kinds of blinking]

The eye movement associated with blinking was studied with a magnetic search coil method. Lid movements and eye movements associated with spontaneous blinks, voluntary blinks, and reflex blinks induced by puffs of air or flashes of light were analysed. Eye movements associated with spontaneous blinks and voluntary blinks had initial downward and adducted movements followed by upward and abducted movements of the eyeball. Reflex blinks initially showed the same downward and adducted movements, but upward and abducted movements were not constantly obtained in given subjects. The velocity-amplitude ratio was equal among the three kinds of blinks in both horizontal and vertical movements. The velocity-amplitude ratio of the eye movements associated with blinks and visually-guided saccadic eye movements was compared. The horizontal and vertical eye movements associated with blinks were slower than those of saccadic eye movements in the same subject. Therefore, the eye movements associated with the blinks may have a different neural mechanism in the brain from that of the saccadic eye movement system.