An eye-movement study on motion inference - Abstract
Background: In motion extrapolation, there are two distinct eye movements during the invisible motion period, namely, smooth pursuit and saccade, and it has been proposed that the saccade compensates for the slowing of smooth pursuit.
Methods: 30 undergraduate students from Xi’an, China were recruited to participate in the experiment based on motion inference task. the onset time of the saccade after target occlusion after target occlusion and the accuracy of motion duration estimation under conditions of different contrast levels of the moving targets were compared. Eyelink 1000 plus was used to collect the eye movement data.
Results: For the fast and slow moving targets, the onset time of the saccades under low contrast condition was significantly longer than that under high contrast condition while for medium-moving target, there was no significant difference. There was no significant difference in the accuracy of motion duration estimation, regardless of the target contrast and velocity.
Conclusions: Anticipatory saccade may be not triggered by smooth pursuit attenuation errors accumulation, and the smooth pursuit after occlusion may have a higher accuracy than the anticipatory saccade. The present study highlights to the underlying mechanism of motion extrapolation, and provides new ideas for the application of eye movement technology in the motion extrapolation test.