Fixation of normal and amblyopic eyes.

During attempts to maintain steady fixation on a small target for 6 s, amblyopic eyes drifted more than did normal eyes. Neither the magnitude of this long-term drift (LTD) nor the SE of eye position correlated with the visual acuity of the amblyopic eye. However, when the SE of eye position was corrected for the LTD, the corrected SE tended to be larger in amblyopic eyes than in normal eyes and correlated with the visual acuity of the amblyopic eye.