Abstract
A torsional optokinetic stimulus drives torsional nystagmus, and a tilted frame during a rod and frame subjective visual vertical (SVV) task affects SVV and biases torsional eye position. We posit that a visual gravity cue provided by a frame in a torsional optokinetic stimulus would further bias torsional nystagmus. In order to test this theory, we use a FOVE VR headset (FOVE Inc., Tokyo, JP, model FOVEVR) to place the subject in a virtual room with circles forming either a rectangular room or a tubular room (frame/no frame). We placed a fixation point at the center of the room while the room rotates at 0°/s, ±6°/s, or ±12°/s. In addition, we had the subject perform a rod and frame SVV task, 0° ± 12° (upright) with nine equidistant divisions, asked twice per condition set. Preliminary data (N = 3) shows that the virtual reality setup produced the expected relationship between the speed of the rotation of the room and the slow-phase velocity of the induced nystagmus as well as the bias in the perception of upright. With the perceived upright tilted in the direction of the rotation. Additionally, we did not find a difference in torsional slow phase velocity (SPV), ocular torsion position, or perception of upright, between the frame and no frame condition across all rotation velocities and no significant difference in the SVV in intersubject results.