Vestibular compensation and nystagmus.

In healthy young subjects barbiturate induced vestibular nystagmus was sequentially studied with repeated electronystagmographic recordings. The analysed data together with our earlier studies indicated that, except for vertical nystagmus, spontaneous and different types of positional nystagmus by themselves are not diagnostic of site of lesion. The transition from spontaneous to positional to paroxysmal nystagmus observed in follow up studies of several of these cases indicates that these various types of vestibular nystagmus are likely a measure and reflection of different degrees of vestibular decompensation.