The effect of toluene on the vestibulo- and opto-oculomotor system in rats. A computerized nystagmographic study.

The short-term effect of exposure to toluene on the vestibulo- and opto-oculomotor system in rats was investigated. Stimulation of the vestibulo- and opto-oculomotor system was either a constant rotatory acceleration, a sinusoidal oscillation, a randomized oscillation or an optokinetic stimulation. Eye movements in response to the different stimulations were recorded by EOG and fed into a computer for analysis. Due to toluene exposure the slow phase velocity gain during constant acceleration increased and the post-acceleratory nystagmus response was prolonged. The optokinetic gain at stimulation velocities above 10 deg/sec decreased during toluene exposure. Toluene also prolonged the duration of optokinetic after- and after-afternystagmus. The findings in this study strongly suggest an effect of toluene on the cerebellum.