Evidence for a range effect in the saccadic system.

There is general belief that saccadic eye movements almost always undershoot by about 10%. It has long been known, however, in manual tracking that there exists a response bias termed the range effect: small distances are overestimated while large distances are underestimated. The present experiments demonstrate that saccades also show a range effect. The use of two different sets of target distances that partially overlap each other showed that saccades can be made to systematically either overshoot or undershoot their targets depending on the locations of the other targets in the set.