Listing's plane rotation with convergence: role of disparity, accommodation, and depth perception

Earlier studies have reported temporal rotation of Listing's plane with con vergence of the eyes causing torsion, which is dependent on eye elevation. The amount by which the planes rotate differs from study to study. To gain insight into the functional significance of the temporal tilt of Listing's plane for vision, we examined whether the rotation of the plane depends on the visual conditions, namely on the stimuli driving vergence. In different conditions, accommodative vergence, disparity-vergence, combinations of di sparity with accommodation or depth perception were used and the resulting rotation of Listing's plane was measured. Our findings show, for the first time, that the relationship between convergence and Listing's-plane tempora l rotation depends on the stimuli driving vergence. When the stimulus conta ins only disparity cues, vergence and Listing's plane rotate immediately an d consistently among subjects. Accommodative vergence, the mutual couplings between vergence and accommodation, can influence the orientation of Listi ng's plane, but they do so in a idiosyncratic way. The largest rotation was elicited by stereograms combining disparity-vergence with depth perception . These findings support the idea of a functional role of Listing's plane r otation for binocular vision, perhaps for depth perception.