Saccade trajectory curvature in visual search using natural scene images

A recent study proposed that saccade trajectories often curve away from previously fixated locations during visual search because of the inhibitory mechanism which prevents inefficient reexamination of rejected distractors. In the present study, we examined whether visual contexts influence saccade trajectories as is the case with other inhibitory effects in visual search (e. g., inhibition of return). Computer-generated natural scenes were used as search stimuli and participants were required to look for a toy car in the scene. The results showed that the saccade trajectories were affected by at least three previous fixations and the effect decreased exponentially with the number of intervening fixations. These results are consistent with the findings in the previous study using abstract stimuli (the O among Cs search task). The relationships between saccade curvature and other inhibitory effects in visual search are discussed.