The role of developmental limitations of sensory input on sensory/perceptual organization

The human infant is born with limited sensory capacities. Such limitations are characteristic of early stages of development of all mammals. These limitations have been conceptualized as equivalent to sensory deprivation, and it has frequently been assumed that compensatory stimulation would therefore be advantageous. It is our contention that, during normal development, limitations provide an organizational framework which enhances perceptual development, and that providing additional stimulation to prematurely born infants may, in fact, be harmful. In addition to reviewing the literature on this issue, we present the results of several studies in which the effect of surgically opening the eyes of rat pups prior to the age of normal eye opening was examined. These studies found alterations in the patterns of homing consequent upon the early availability of visual input. Pups whose eyes were opened early failed to exhibit the transitions in behavior normally found to occur around the time of eye opening. Furthermore, the pups failed to respond differentially to olfactory stimuli which littermate controls successfully discriminated.