SUMMARY

(1) Monocularly (MD) and binocularly deprived (BD) cats were tested to determine the permanence of previously described behavioral deficits on a visual perimetry test. Three group I MD cats and 2 group I BD cats had both eyes open as adults for up to 2 years before testing. At a similar time before testing, 2 group II MD cats had a reverse-suture operation (deprived eye open, non-deprived eye shut), and 2 group II BD cats had the right eye open. (2) Group I cats showed no recovery from previously described eficits. The MD cats had a normal visual field for the non-deprived eye (from 45 ° contralateral to 90 ° ipsilateral), but with the deprived eye responded only to objects in the monocular segment (60°-90 ° ipsilateral) while ignoring objects throughout the binocular segment (45 ° contralateral-45 ° ipsilateral). The BD cats with each eye responded to objects only in the ipsilateral hemifield, ignoring the contralatera145 ° field of view. (3) Group II cats with the open, deprived eye had deficits identical to the above indicating that lack of usage of the non-deprived eye resulted in no improvement of visual field for the deprived eye. The group II BD cats, when monocularly tested 4 h after opening of the left eye, displayed visual behavior similar to that seen for the right eye. (4) Given the techniques used in this experiment, it is concluded that MD and BD cats develop permanently reduced visual fields as a result of their early visual deprivation