An Experimental Study of Optokinetic Responses

A NORMAL person, as Walsh1and others have pointed out, will exhibit an optokinetic (or opticokinetic) nystagmus on watching a succession of stationary objects as he moves steadily past them, such as the telegraph poles seen from a moving train. Likewise, it may appear if his eyes follow a series of moving objects, such as the stripes on an optokinetic drum. A nystagmus of this type consists of a following movement, or a slow phase, and a quick return of the eyes to center, or a quick phase. The slow phase depends upon fixation of the eyes. Various ophthalmologists have stated that such a nystagmus may be avoided if the subject being tested will visualize some object beyond the optokinetic drum during the test (Walsh1) or will fix his attention on something other than the drum (Kestenbaum2). However, as will be seen, not all observers (Cogan and