Effects of blindfolding a unilateral eye on so-called central nystagmus.

A bipolar stimulating electrode was chronically implanted at the mesodiencephalon in the rabbit to induce so-called central nystagmus. The nystagmus was remarkably facilitated in either darkness by blindfolding an eye ipsilateral to the stimulation site, but the nystagmus was almost never facilitated by blindfolding an eye contralateral to the stimulation site. This is a phenomenon related to photic inhibition. This phenomenon disappeared after ablation of the flocculus and paraflocculus ipsilateral to the stimulation site. The neural pathway responsible for it is considered to be by way of the flocculus.