Temporal limits of the susceptibility of depth perception to proprioceptive deafferentations of extraocular muscles

In a prewous study, extraocular muscle propnoceptlon (E O M P ) was shown to play an important role in the postnatal development of depth perception following unilateral or bdateral sections of the ophthalmic branch of the trlgemmal nerve (V:h nerve) performed at 6-8 weeks of age, the binocular thresholds were 2 to 3 times higher than m control animals Since the Vl-Sectlons produced no deficits when performed m adults, the temporal hmlts of a period of susceptibility remained to be determined In order to assess the lower and upper hmlts of the period during which these perceptual deficits could be induced, unilateral or bilateral V:secttons were performed in k~ttens at different ages Depth perception thresholds were measured by using the lumping stand techmque Sections of the V 1 nerve only produced significant impairments of the binocular depth thresholds when performed after 3 weeks of age They could be observed when umlateral sections were performed at up to 13 weeks of age and with bdateral sections at up to 10 weeks of age These functional impairments appeared to remain permanently through adult hfe