Effect of previously fixated locations on saccade trajectory during free visual search.

Recent studies have shown that the saccade trajectory often curved away from an object that was previously attended but irrelevant to the current saccade goal. We investigated whether such curved saccades occur during serial visual search, which requires sequential saccades possibly controlled by inhibition to multiple locations. The results show that the saccade trajectories were affected by at least three previous fixations. Furthermore, the effect of the previous fixations on saccade trajectories decreased exponentially with time or the number of intervening saccades. The relationship between the curved saccade trajectory and inhibition of return during serial visual search was discussed.