Vertigo as reflected by the nystagmogram. A clinical analysis.

Efforts to evaluate findings in the nystagmogram were made in a material of 338 vertiginous and dizzy patients. A spontaneous nystagmus, a positional nystagmus as well as a difference in caloric reactivity are as solitary findings of lettle value for revealing peripheral disorders. On the other hand, central disturbances are frequently revealed by inability to track a moving optic target, resulting in an irregular or a saccadic pattern, by persistence of vestibular nystagmus in light, by persistence of such nystagmus at eye-closure, by an increase in spontaneous nystgmus on eye-closure or by dysrhythmic nystagmus in caloric tests. Cases of functional vertigo seem to differ from cases of vertigo from other sources by their increase of spontaneous nystagmus (when present) or by persistence of caloric nystagmus on eye-closure.