ABSTRACT The accommodative response (AR) to disparity‐vergence and blur stimuli was determined for 45 subjects; 15 emmetropes, 15 late‐onset myopes (LOM's), and 15 early‐onset myopes (EOM's). The accommodative response was measured at approximately 1‐s intervals for 50 s using an objective infrared optometer. Disparity‐driven accommodation was induced by a 4δ base‐out prism at accommodative stimulus levels of 2.50 and 3.25 D. LOM's show significantly higher levels of disparity‐induced accommodation when compared with the other two refractive groups. Blur‐induced accommodation was produced by increasing the accommodative stimulus from 2.50 to 3.25 D with no concomitant change in vergence stimulus. EOM's exhibit less blur‐induced accommodation compared with LOM's and emmetropes. These results are discussed with reference to differences in accommodation‐vergence synkinesis between LOM's and EOM's, and in relation to the etiology of late‐onset myopia.
Rosenfield et al. (Tue,) studied this question.