Accommodative convergence response to off-foveal retinal images.

A special stimulus device was designed and developed to present blur stimulation through off-foveal retinal images. An infrared reflecting eye movement monitor was used to measure the dynamic accommodative convergence response to both foveal and off-foveal blur stimulation. In most subjects studies a substantial off-foveal accommodative vergence response was found; however, this response diminished rapidly as image distance from the fovea increased. Considerable variation in the response was noted between subjects, and, to a lesser extent, in the same subject for left-versus-right off-foveal image positions.