How Is Language Acquired

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Language
tones, facial expressions, and endless repetitions. Once they have a word for an object,
they may “overextend” it to cover more ground. So they might use doggy to refer to
cats, bears, and horses; they might use fly for all insects and perhaps for other small
things such as raisins and M&Ms (Clark, 1983, 1993). Children make these “errors”
because their vocabularies are limited, not because they fail to notice the difference
between dogs and cats or because they want to eat a fly (Fremgen & Fay, 1980; Rescorla,
1981). Being around people who don’t understand these overextensions encourages
children to learn and use more precise words (Markman, 1994). During this period,
children build up their vocabularies one word at a time. They also use their limited
vocabulary one word at a time; they cannot yet put words together into sentences.
The one-word stage of speech lasts for about six months. Then,
sometime around eighteen months of age, children’s vocabularies expand dramatically
(Gleitman & Landau, 1994). They may learn several new words each day, and by the
age of two, most youngsters can use fifty to well over one hundred words. They also
start using two-word combinations to form efficient little sentences. These two-word
sentences are called telegraphic because, like telegrams or text messages, they are brief
and to the point, leaving out anything that is not absolutely essential. So if she wants
her mother to give her a book, a twenty-month-old might first say, “Give book,” then
“Mommy give,” and if that does not work, “Mommy book.” The child also uses rising
tones to indicate a question (“Go out?”) and emphasizes certain words to indicate location (“Play park”) or new information (“Big car”).
Three-word sentences come next in the development of language. They are still
telegraphic, but more nearly complete: “Mommy give book.” The child’s sentences now
begin to have the subject-verb-object form typical of adult sentences. Other words and
word endings begin appearing, too. In English, these include the suffix -ing, the prepositions in and on, the plural -s, and irregular past tenses (“It broke,” “I ate”; Brown,
1973; Dale, 1976). Children learn to use the suffix -ed for the past tense (“I walked”),
but they often overapply this rule to irregular verbs that they had previously used correctly, saying, for example, “It breaked,” “It broked,” or “I eated” (Marcus, 1996).
Children also expand their sentences with adjectives, although at first they make some
mistakes. For example, they are likely to use both less and more to mean “more” (Smith
& Sera, 1992).
The Second Year
The Third Year and Beyond By age three or so, children begin to use auxiliary
verbs (“Adam is going”) and to ask questions using what, where, who, and why. They
begin to put together clauses to form complex sentences (“Here’s the ball I was looking for”). By age five, children have acquired most of the grammatical rules of their
native language.
LINKAGES
How do we learn to speak?
(a link to Human Development)
one-word stage A stage of language
development during which children
tend to use one word at a time.
How Is Language Acquired?
Despite all that has been learned about the steps children follow in acquiring language,
mystery and debate still surround the question of just how they do it. We know that
children pick up the specific content of language from the speech they hear around
them: English children learn English; French children learn French. But how do children come to follow the rules of grammar?
Conditioning, Imitation, and Rules Perhaps children learn grammar because
their parents reward them for using it. This idea sounds reasonable, but observational
research suggests that positive reinforcement (which we describe in the learning chapter)
is not the main character in the story of language acquisition. Parents are usually more
concerned about what is said than about its grammatical form (Hirsch-Pasek, Treiman, &
Schneiderman, 1984). So when the little boy with chocolate crumbs on his face says, “I not
eat cookie,” his mother is more likely to respond, “Yes, you did” than to ask the child to
say, “I did not eat the cookie” and then praise him for his grammatical correctness.
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Chapter 7 Thought, Language, and Intelligence
Learning through modeling, or imitation, appears to be more influential. Children
learn grammar most rapidly when adults demonstrate the correct form in the course
of conversation. For example:
Child:
Mother:
Child:
Mother:
Mommy fix.
Okay, Mommy will fix the truck.
It breaked.
Yes, it broke.
But if children learn grammar by imitation, why do children who at one time said
“I went” later say “I goed”? Adults don’t use this form of speech, so neither imitation
nor reward can account for its sudden appearance. It appears more likely that children
analyze for themselves the underlying patterns in the language they hear around them
and then learn the rules governing those patterns (Bloom, 1995).
The ease with which children the
world over discover these patterns and develop language has led some to argue that
language acquisition is at least partly innate, or automatic. Noam Chomsky (1965)
believes that we are born with a built-in universal grammar, a mechanism that allows
us to identify the basic dimensions of language (Baker, 2002; Chomsky, 1986; Nowak,
Komarova, & Niyogi, 2001). According to Chomsky, a child’s universal grammar might
tell the child that word order is important to the meaning of a sentence. In English,
for example, word order tells us who is doing what to whom (the sentences “Heather
dumped Jason” and “Jason dumped Heather” contain the same words, but they have
different meanings). In Chomsky’s view, then, we don’t entirely learn language—we
develop it as genetic predispositions interact with experience (Senghas & Coppola,
2001). So a child’s innate assumption that word order is important to grammar would
change if the child heard language in which word order did not have much effect on
the meaning of a sentence.
Other theorists disagree with Chomsky, arguing that the development of language
reflects the development of more general cognitive skills, not just innate, languagespecific mechanisms (e.g., Bates, 1993). Still, there is other evidence to support the existence of biological factors in language acquisition. For example, the unique properties
of the human mouth and throat, the language-related brain regions described in the
chapter on biology and behavior, and genetic research all suggest that humans are
Biological Bases for Language Acquisition
LEARNING A SECOND LANGUAGE
As these international students are
discovering, people who learn a second
language as adults do so more slowly,
and with less proficiency, than younger
people (Johnson & Newport, 1989;
Patkowski, 1994) and virtually never
learn to speak it without an accent
(Lenneberg, 1967). Still, the window of
opportunity for learning a second language remains open long after the end of
the critical period in childhood during
which first-language acquisition must
occur (Hakuta, Bialystok, & Wiley, 2003).