Release of pursuit eye movements using after-images.

Abstract : It is frequently asserted that a moving visual target is necessary in order for the eyes to make slow, conjugate pursuit movements. Some subjects, however, indicating that an internal proprioceptive motion signal may be sufficient for pursuit. After-images provide another example where smooth movements can be made without any moving visual target. The test of the uncancelled corollary discharge hypothesis is to monitor the miniature eye movement patterns while having a stabilized image (e.g. an after-image) present and see if a directional microsaccade always precedes the onset of pursuit. Tests results are reported. (Author)