A Study on Saccade System

Research Project

Project/Area Number	61510038
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Psychology
Research Institution	Niigata University
Principal Investigator	HONDA Hitoshi Faculty of Humanities, Associate Professer, 人文学部, 助教授 (50124623)
Project Period (FY)	1986 – 1987
Project Status	Completed (Fiscal Year 1987)
Budget Amount *help	¥2,400,000 (Direct Cost: ¥2,400,000) Fiscal Year 1987: ¥200,000 (Direct Cost: ¥200,000) Fiscal Year 1986: ¥2,200,000 (Direct Cost: ¥2,200,000)
Keywords	Eye Movements / Saccade / 空間定位 / 視覚的空間定位
Research Abstract	In the present study, we examined (1) whether the amplitude of a saccade (quick eye movement) is determined by a retinal information (distance between the fovia and the image of a visual stimulus on the retina) or by the actual position of the stimulus, and (2) whether a saccade is a ballistic movement which once occurred can not change its direction and amplitude. To this purpose, we compared the accuracy of the subjects' perceptual and oculomotor (saccadic) localizations of a visual stimulus flashed near the time of a prior saccade. The main results were as follows. 1. The perceptually localized position of the visual stimulus flashed near the time of a prior saccade was different from its actual position. The mislocalization occurred from about 100 msec before the saccade onset, and continued about 100 msec after the end of the saccade. 2. The saccadic response to that visual stimulus directed not to its actual position but to its apparent (perceptually judged) position. This is not consistent with the results of early studies which have been accepted as evidence for "spatial model" of the saccade system. 3. The analysis of amplitudes and latencies of the saccadic responses showed that the saccade system is not ballistic, and that it has an ability of parallel processing.