Fig. 11.

Animals with acute bilateral vestibular loss can still produce trajectories with “virtual VOR” segments during gaze fixation. Solid lines are control, and dashed lines represent acute stage of vestibular loss using the monkey default parameters (set 1 in Table 2), except that in the lesion case the healthy semicircular canals are replaced with plugged canals (see appendix for dynamic changes) and a 50% reduction of the head velocity estimate is imposed for feedback to SC (reduced from 1 to 0.5). Eye-head coordination patterns appear normal in plugged monkey, including a VOR-like reversal of eye velocity during fixation, but gaze itself is hypermetric, as reported by Newlands et al. (1999).