Central Nystagmus. II. Relationship Between Central and Labyrinthine Nystagmus

¹ From the Department of Pharmacology and the Electronic Laboratory, Hebrew University-Hadassah Medical School, Jerusalem, Israel

Rotation of a rabbit influences the ‘central’ nystagmus, provoked by electrical stimulation of a nystagmogenic area in the mesodiencephalon, in opposite sense during the acceleratory and deceleratory period, respectively. Nystagmic movements, produced by simultaneous central and labyrinthine stimulation, show enhancement, when they posses identical direction, and suppression, when their directions are opposite. The same rule applies to superposition of central and caloric nystagmus, the latter resulting from temperature changes near the tympanic membrane. When electrical stimulation is stopped, central nystagmus often increases its frequency for a short period.