Examination of Lower Level Motion Mechanisms That Provide Informationto Object Tracking: An Examination Using Dichoptic Stimulation

摘要

In this study, we examined the operation of first- and second-order motionmechanisms with respect to object tracking using dichoptic presentation. Abistable apparent motion stimulus composed of four rectangles arranged insquare- and diamond-shapes in every other frame was presented binocularly,monocularly, or dichoptically using a stereoscope. Since past motion studiesshowed that the first-order motion mechanism cannot function under dichopticstimulation, we evaluated the upper temporal frequency limits of object trackingwith dichoptic presentation and compared these results with those obtained withordinary binocular or monocular (nondichoptic) presentation. We found that thetemporal limits were 4 -5 Hz, regardless of the viewing conditions. These limitsare similar to those for within-attribute (first- and second-order) objecttracking (4 -5 Hz) obtained in our previous study. Thus, this putative mechanismmay be responsible for object tracking, based only on second-order components,even in the case of first-order stimuli.