Postural stability in primary open angle glaucoma.

Background: This study evaluated the visual contribution to postural steadiness in primary open angle glaucoma (POAG), in correlation with the mean deviation (MD) measured through conventional perimetry, and with the Advanced Glaucoma Intervention Study (AGIS) score, which quantifies the extent of losses in the visual field.

Methods: In 35 POAG patients and 21 age-matched normal subjects, the sway of the centre of pressure of the feet, on a firm or foam support, was recorded. The subjects stood on a force-plate with eyes closed, or with one or two eyes open.

Motion perception in glaucoma patients: a review.

Most of the histopathological and psychophysical studies in glaucoma reveal a preferential damage to the magnocellular (M) pathway although a few of them support a damage to the parvocellular (P) pathway as well. In glaucoma, the visual fields are usually evaluated by conventional perimetry. However, it has been demonstrated that 20-40% of ganglion cells are lost before field defects are detected using conventional perimetry.

Absolute distance perception during in-depth head movement: calibrating optic flow with extra-retinal information.

We investigated the ability of monocular human observer to scale absolute distance during sagittal head motion in the presence of pure optic flow information. Subjects were presented at eye-level computer-generated spheres (covered with randomly distributed dots) placed at several distances. We compared the condition of self-motion (SM) versus object-motion (OM) using equivalent optic flow field.

Visual perception of planar orientation: dominance of static depth cues over motion cues.

We measured the ability to report the tilt (direction of maximal slope) of a plane under monocular viewing conditions, from static depth cues (square grid patterns) and motion parallax (small rotations of the plane about a frontoparallel axis). These two cues were presented separately, or simultaneously. In the latter case they specified tilts that were either collinear (coherent case) or orthogonal (conflict case).