Endogenous saccades are preceded by shifts of visual attention: evidence from cross-saccadic priming effects

The present study examines whether endogenous saccades are preceded by shifts of attention. Three experiments are reported in which participants were required to execute a saccadic eye movement to a certain location and to subsequently identify the orientation of a target triangle. Prior to the execution of the saccade a prime was presented, which was compatible or incompatible with the target. A priming effect (faster responses in the compatible condition than in the incompatible condition) occurred only when the prime was presented at the saccade destination, and this effect was larger when the prime was presented during oculomotor programming than when it was presented prior to oculomotor programming. The results indicate that an endogenous shift of attention precedes endogenous saccades, providing further support for theories of visual selection that assume a tight coupling between attention and saccades.