Visual-evoked responses from strabismic cats. A comparison of esotropes with exotropes

We examined cortical responses evoked by 8-Hz, phase-shifted sine wave gratings at a range of contrasts and spatial frequencies in normal cats and in cats raised with artificial esotropia or exotropia. There were no significant differences between the amplitudes of the responses evoked through the two eyes of the normal cats, but for some esotropes and exotropes the responses evoked through the unoperated eye were larger than those evoked through the operated eye. Interocular response differences were comparable in all affected cats and were most pronounced at high contrasts. These results indicate that rearing with artificial strabismus can produce amblyopia in both esotropes and exotropes, and that the amblyopia is similar in the two cases.