Concurrent processing of saccades

We summarize several experiments indicating that the saccadic system is capable of simultaneously programming two movements toward different goals. This concurrent processing of saccades can lead to the execution of two saccades separated by an extremely short intersaccadic interval. This supports the idea of target competition proposed in Findlay & Walker's article, but suggests a greater degree of parallel processing. We provide evidence that concurrent processing of two saccades is not limited to higher-level planning subsystems; rather, it also involves both regions close enough to the motor output that it can systematically affect saccade trajectory.