METHODS. We measured the covariation between these four abilities in children 4 to 9 years of age (n1⁄472) with strabismus, anisometropia, or mixed strabismus/anisometropia, and unaffected controls. Children reported the orientation of a target (a modified ‘‘Pac-Man,’’ similar to Landolt-C stimuli) using four ‘‘ghosts’’ as references. Using a modified staircase procedure we measured threshold s...

A great deal of studies using different visual tasks (e.g., Vernier acuity tasks, tilt illusion, crowding, etc) have revealed that our perception is strongly influenced by the orientation of the stimulus. Most studies have investigated visual acuity in twodimensional visual spaces (2D) but little is known about the effect of line orientation in depth perception (3D). In one experiment, Vernier ...

PURPOSE We set out to determine whether individuals with central field loss benefit from using two eyes to perform a grasping task. Specifically, we tested the hypothesis that this advantage is correlated with coarse stereopsis, in addition to binocular summation indices of visual acuity, contrast sensitivity, and binocular visual field. METHODS Sixteen participants with macular degeneration ...

In our previous studies, we showed that monocular perception of 3D shapes is based on a priori constraints, such as 3D symmetry and 3D compactness. The present study addresses the nature of perceptual mechanisms underlying binocular perception of 3D shapes. First, we demonstrate that binocular performance is systematically better than monocular performance, and it is close to perfect in the cas...

AIMS/BACKGROUND The basis of binocular single vision in microtropia remains a matter of contention. This paper discusses the implications of recovery, in a group of primary microtropes following treatment, in relation to current concepts on the aetiology of the condition and proposed retinocortical correspondence. METHODS Nine previously untreated primary microtropes whose condition resolved,...