Relation between Attention and Characteristics of Saccade during Tracking Eye Movement

Abstract

AbstractUntil now a satisfactory tracking eye movement control model has not been constructed. It is understood that the tracking eye movement characteristics are affected by the attention of the subject, for which, however, no study has been made. This paper considers the visual feedback called target brightness feedback, where the information concerning the accuracy of tracking and the moving target is fed back to the subject through the change of brightness of the target. By this method, the attention of the subject tracking a moving target is invoked. The saccadic motion is especially examined in detail. The saccade is observed to decrease with the increase of attention. As a result of more detailed analysis, it was observed that the position error at the start of the saccade is increased and the ratio of the saccadic amplitude to the position error is decreased. Those properties can be accounted for on the control model as the enlargement of the saccadic dead zone, and the decrease of the adjusting gain for position error, which is a new‐control element added to the model. It was also examined at which point on the retina the target is recognized. There was observed a tendency that the tracking is made at the periphery with the increase of attention. Those phenomena are considered as due to the avoidance of saccadic suppression.