Jerk nystagmus: some new findings.
Eye movements in a subject with jerk nystagmus were recorded during a variety of tracking tasks using a photoelectric method. New findings included ability to reduce nystagmus amplitude and frequency when instructed "to hold the eye steady" rather than "to fixate" in the presence of a visible target, changes in nystagmus characteristics and visual acuity as a function of head position which related to overall retinal-image motion, marked variability of nystagmus especially during reading, and necessity of a prolonged period of visual feedback for generation of nystagmus to approach a "steady-state" level. Clinical implications of these findings are discussed, including use of the "hold" command during ophthalmoscopy in patients with nystagmus.
D000328:Adult; D005246:Feedback; D005260:Female; D005403:Fixation, Ocular; D006257:Head; D006801:Humans; D008722:Methods; D009759:Nystagmus, Pathologic / Q000175:diagnosis*; D011187:Posture; D014792:Visual Acuity; D014836:Volition