Optokinetic afternystagmus and postrotatory nystagmus in squirrel monkeys.

Regardless of whether the direction of optokinetic stimulus matches or conflicts with that of vestibular stimulus, if the squirrel monkey subject has a good target pursuing ability, the enhancement or inhibition of post-stimulatory nystagmus occurs. The nature of the stimuli to provoke optokinetic afternystagmus and post-rotatory nystagmus are not the same, but the similarity of response characteristics and cross-interaction strongly suggest the existence of a common neural linkage between the stimulus receptor and reactor.