Interocular transfer in normal humans, and those who lack stereopsis

Interocular transfer of the tilt after effect was investigated in normal humans with good stereopsis and in subjects without stereoscopic vision. These latter subjects were divided into 2 groups: those with and those without a history of strabismus. Strabismic subjects showed grossly reduced interocular transfer of the effect (12% mean transfer). Nonstrabismic subjects had moderate transfer (49%) and normal subjects showed approximately 70% mean transfer. All normal subjects showed greater transfer from the dominant eye to the nondominant than vice versa. The results are discussed with respect to developmental effects in the visual system of cats and humans, and the nature of the tilt after effect.