C57BL/6 mice showed adaptation in the HOKR. (A) Examples of the averaged eye position traces before and after 60 min of sustained screen oscillations. (B) Changes in HOKR gains during continuous screen oscillations in individual mice. The screen was oscillated at a maximum velocity of 5.2°/s (10° at 0.17 Hz). Ten of 12 mice, indicated by solid lines, exhibited increased gains at 1 h. Only two of these 12 mice showed a decrease in the HOKR gain at 1 h (broken lines). (C) Stimulation parameter-dependence of the adaptation of the HOKR. The screen oscillation at low velocity (5° at 0.11 Hz, 1.7°/s) induces relatively small retinal slips (see Fig. 2A). The sustained oscillation of the turntable by 10° at 0.17 Hz in darkness induced no retinal slips. These results suggest that exposure to a sufficient amount of retinal slips is required for the adaptation of the HOKR. ∗, P < 0.05, Student’s t test.