Effect of scene transitions on transsaccadic change detection in natural scenes

MES During rapid eye movements (saccades) the entire visual scene streams rapidly across the retina. However, this streaming is not usually apparent, due to a reduced visual sensitivity toward motion during saccades.

Magnitude estimation technique was used to estimate the perceived magnitude of whole-scene image displacements made either during saccades (transsaccadically) or intersaccadically. Estimates for the detected transsaccadic shifts were significantly smaller than the intersaccadic shifts.

A further experiment examined the detectability of scene translations as function of relative direction between the translation and saccade. Subjects were more sensitive to changes that were orthogonal compared to collinear with the saccade. Furthermore, subjects were more likely to detect vertical transitions while making horizontal saccades than detecting horizontal transitions while making vertical saccades.

These results suggest that during saccades, the velocity signal appears to be attenuated. Further, the degree of suppression is a function of the direction of the change relative to the eye movement.