1 4th International Congress of Wavefront Sensing and Aberration-free Refractive Correction (Supplement to the Journal of Refractive Surgery; June 2003) ADAPTIVE OPTICS FOR VISION: THE EYE’S ADAPTATION TO ITS POINT SPREAD FUNCTION

Despite ocular aberrations blur the retinal images, our subjective impression is that the visual world is sharp what may suggest that the visual system compensates for their subjective influence. If the brain adjusts for the specific aberrations of the eye, vision should be clearest when looking through the normal wave aberration rather than through an unfamiliar one. The use of adaptive optics techniques to control the eye’s aberrations allows performing experiments to evaluate this hypothesis. We used adaptive optics to produce point-spread functions (PSFs) that were rotated versions of the eye’s usual PSF by angles in 45 degrees intervals. Five normal subjects were asked to view a stimulus with their own PSF or with a rotated version. The subject’s task was to adjust the magnitude of the aberrations in the rotated case to match the subjective blur of the stimulus to that seen when the wave aberration was in the normal orientation. The magnitude of the rotated wave aberration required to match the blur with the normal wave aberration was 20 to 40 % less, indicating that the subjective blur for the stimulus increased significantly when the PSF was rotated. These results support the hypothesis that the neural visual system is adapted to the eye’s particular aberrations. This result has important implications for methods to correct higher orde