Influence of retinal lesions on grating acuity of the cat

Grating acuity was investigated behaviorally in the cat. Retinal lesions of increasing diameter centered on the area centralis were made by photocoagulations in one eye, while the intact eye was used as control. Lesion size evaluated from fundus photographs was precisely correlated with the anatomical lesion size measured in retinal whole mounts. Grating acuity improved with increasing grating area in cats with intact retinae and after small (less than 3 degrees diameter) retinal lesions but not after large lesions (greater than 4 degrees diameter). Overall, grating acuity clearly decreased when lesions became larger than 4 degrees in diameter. The acuity-eccentricity relationship closely fits the cutoff frequency of brisk sustained cells at the corresponding eccentricities.