Abstract: This study investigated whether the spatial shift of attention was involved in the process of endogenous saccades with illusory line motion. In Experiment 1, the pattern of spatial attention shift was examined by instructing participants to saccade to the cue. In Experiment 2, whether illusory line motion was affected by pre-attention processing was tested by requiring participants to detect the target while focusing on the fixation. In Experiment 3, participants were required to saccade to the opposite side of the cue, in order to inspect the effect of spatial congruence between saccade and the cue on attention shifts. Therefore, whether detection of the cue was one of the factors in determining attention shift could be confirmed. The main findings are as follows:(1) Spatial shift of attention is necessary to execute endogenous saccades; (2) Attention is not guided by pre-attention processing while the eye is focused on the fixation, and (3) The effect of spatial congruence between saccade and the cue on attention shifts is not significant.

Key words: ndogenous saccades, spatial shift of attention, illusory line motion, pre-attention processing