[Visual inhibition of the ampullar rotational-acceleratory excitation]

We have studied in normal subjects, the monocular and binocular influence on the nystagmus provoked by angular acceleration. The results show that the fixation determines a reduction of all quantitative parameters of the nystagmic response that, in the binocular fixation condition, is nearly 80% and halves with monocular fixation. The data shows activity conditions in a simple summation report of the values of visual input and demonstrate not only that the quality of the visual inhibition is, in normal subjects, perfectly equivalent between the two eyes but also that the stimulations evoked in the two labyrinths, convergent to the equilibrium centres, integrate in a perfectly complementary way. We have to study how this complex and harmonious polysensorial activity deteriorates with pathologic alterations of the visual and ampullar systems.