Figure 2: Recordings of horizontal (blue) and vergence (red) slow phase eye velocity (SPV) in one typical subject with the head aligned with the trunk during several cycles of OVAR in darkness at both 0.125 Hz and 0.5 Hz.

The horizontal SPV was modulated by the sinusoidally varying linear velocity about the head inter-aural axis (blue). The vergence SPV was modulated by the sinusoidally varying linear velocity about the head naso-occipital axis (red).