Depth perception after infant and adult visual neocortical lesions in light- and dark-reared rats

In 2 experiments the behavior of light- and dark-reared infant- and adult-operated striate rats were compared at 20-160 days of age on a visual cliff apparatus in which the depth of the deep side could be varied. Differential depth thresholds revealed that depth discriminative ability did not develop normally following removal of the striate cortex in infancy. Further, infant-operates who were reared in darkness following their operations performed less well than their light-reared, infant-operated counterparts. The infant-operated animals, regardless of their postoperative rearing condition, performed significantly better than did adult-operated animals after comparable post-operative recovery periods and testing. The results are discussed in terms of further specification of the role played by age of operation and by the interaction between visual experience and age of operation.