Educability-and-Group-Differences-1973-by-Arthur-Robert-Jensen

Language Deprivation 285
In these aspects, language acquisition can be likened to the child’s
learning to walk. All physically normal children learn to do so,
given the barest opportunity, and they go through the same
sequence from crawling, creeping, and toddling to walking, although
showing slight individual differences in rates of acquisition at each
stage along the way. Houston points out that . . languageacquisition
stages seem invariant; it should be additionally noted
that all children have rules by which they produce their language
at each stage of the acquisition process, irrespective of the particular
language or form of language they are acquiring [three references]’
(p. 951).
Is the later lag in cognitive development seen in low SES
children and especially in low SES Negro children, between
grades 1 and 3, due to delayed effects of verbal deprivation during
the preschool years or to insufficient verbal stimulation outside
school Does language deficiency per se hinder conceptual and
abstract thinking In seeking answers to these questions, it should
be instructive to study the most verbally deprived children we
know of - children who are born totally deaf. Since the year 1900
there have been some fifty comparative studies of the intelligence
of the congenitally deaf; all these studies have been reviewed and
summarized in two articles by M. Vernon (1967, 1968). As
might be expected if deafness constitutes a severe form of verbal
and language deprivation, congenitally deaf children score well
below normally hearing children on strictly verbal tests. At age of
school entry, when normal children have a vocabulary of 2,000
to 8,000 words and a well-developed syntax, deaf children usually
know absolutely no words at all, and it is only after about four
years of education, at about ten years of age, that these children
can begin to compete with the average first grader in vocabulary
and other language skills; about 35 percent of such children never
achieve functional literacy, so great is their verbal handicap.
But how do these deaf children score on non-verbal performance
tests of intelligence Vernon summarizes his review of all the
literature on this point: *. . . the research of the last fifty years
which compares the IQ of the deaf with the hearing and of subgroups
of deaf children indicates that when there are no complicating
multiple handicaps, the deaf and hard-of-hearing function at
approximately the same IQ level on performance tests as do the
hearing’ (1968, p. 9),4 contrary to the popular view that the deaf are