Children Deprived of Access to Some of the Meanings
The extraordinarily robust nature of language development is also apparent when we consider language learning in the absence of vision. Imagine a child who hears, Look!There’s a big dog! or Do you see that man playing the guitar? Surely, the child will find iteasier to grasp the meaning of these phrases if she can observe the dog or the guitar player, using the perceptual experience to help decode the linguistic input. This would seem to suggest that language learning would proceed slowly or be distorted in a blind child cut off from many of the learning opportunities available to the sighted child. Remarkably, though, the evidence shows that blind children learn language as rapidly and as well as sighted children. One particularly striking example is vision-related words like look and see, which blind children use as early (2 years old) and as systemat-ically as sighted children. Of course, there are differences in how blind and sighted chil-dren understand these words. A young sighted listener asked to look up!will tilt her face upward (even if her vision is blocked by a blindfold). For this child, look clearly refers to vision (Figure 10.32A). A congenitally blind child, when given the same command pro-duces a different—but entirely sensible—response. Keeping her head immobile, she
reaches upward and searches the space above her body with her hands (Figure 10.32B; Landau & Gleitman, 1985). Thus, each of these children understands look to be an instruction to search a bit of the world by use of the sense organs.
Not only do these input-deprived youngsters come to understand terms that refer to sight for those of us with normal vision, but they also know much about the application of color terms. Perhaps it is not so surprising that a blind 5-year-old can respond to the query Can a cow be green? by saying I think they are usually brown or white for he might on some occasion have heard the phrase a brown cow uttered by sighted adults, and never a green cow. But to the query Canan idea be green? the blind child does not wildly guess at some color, but can sensibly answer No, that’s silly; ideas are not any color; they are only in your head. All this knowledge without any personal experience of colors at all!
Once again, we see that language and even apparently sight- dependent concepts emerge in considerable complexity and on schedule despite a dra- matic shift away from the standard circumstances of learning. This provides further support for the claim that language is a truly basic factor in human nature. Prepared as the human child is to acquire a language, its learning can proceed despite significant sensory deprivation.