Binocular coordination in response to two-dimensional, three-dimensional and stereoscopic visual stimuli

We were particularly interested in whether binocular coordination when viewing stereoscopic images would be more comparable to when viewing a 2D representation, or when viewing a real stimulus array in depth.Data are reported from an experiment examining binocular coordination in response to stereoscopically presented stimuli. Movements of both eyes were recorded as participants viewed LED stimuli in a real scene with depth, a 2D image of the scene, and a stereoscopic image of the scene.When viewing real LEDs, vergence during saccades re-aligned the eyes in depth where necessary, with smaller adjustments during the following fixation. In contrast, when viewing the stereoscopic representation, vergence during saccades did not re-align the eyes in depth. The only effect of target depth on vergence occurred during the following fixation.We conclude that disparity in parafoveal objects, in isolation from other depth cues (and, minimally, conflicting with blur), was insufficient for the visual system to target saccades appropriately in depth.