Figure 4. MVI002 VOR response magnitude depends on electrode location and stimulus intensity.

Peak left eye excitatory slow phase velocity component about the target canal’s axis as a function of percentage of current amplitude intensity during initial stimulation of subject MVI002 via all functional electrodes in the left (A) posterior, (B) horizontal, and (C) anterior semicircular canals using 2-Hz–modulated, 40% duty cycle pulse train alternating between 0 and 200 pps. Each data point depicts mean ± SD for n = 7–19 (median 14) cycles. Current intensity 10% denotes minimum current that evoked a detectable eye movement response; 100% denotes maximum current tested for that electrode contact and phase duration. E11 not tested due to a high impedance (>25 kΩ). Supplemental Table 3 shows complete mappings of current intensity to pulse amplitude in microamps for each subject. For each ampulla in MVI002, 1 of 3 electrodes clearly outperforms other contacts 700–1100 μm away.