We introduced the idea that children come equipped with the means necessary for understanding their worlds when considering physical and biological concepts. It should not be surprising that infants also possess
BOX 4.2
How Many?
How do 3- to 5-year old children react when they encounter unexpected changes in the number of items? Before the dialog below, children had been playing with five toy mice that were on a plate; the plate and mice were then covered and the experimenter surreptitiously took away two mice before uncovering the plate (Gelman and Gallistel, 1978:172). What follows is one child’s attempts to recon- cile the differences in the number of mice:
Child: Must have disappeared. Experimenter: What?
Child: The other mousses?... Experimenter: How many now?
Child: One, two, three.
Experimenter: How many at the beginning of the game?
Child: There was one there, one there, one there, one there, one there.
Experimenter: How many?
Child: Five—this one is three now but before it was five. Experimenter: What would you need to fix the game?
Child: I’m not really sure because my brother is real big and he could tell.
Experimenter: What do you think he would need?
Child: Well I don’t know...Some things have to come back. Experimenter: [Hands the child some objects including four mice]. Child: [Puts all four mice on the plate]. There. Now there’s
one, two, three, four, five, six, seven! No...I’ll take these [points to two] off and we’ll see how many. Child: [Removes one and counts]. One, two, three, four,
five; no—one, two, three, four. Uh...there were five, right?
Experimenter: Right.
Child: I’ll take out this one here [on the table] and then we’ll see how many there is now.
Child: [Takes one off and counts]. One, two, three, four, five. Five! Five.
such mechanisms for learning language. They begin at an early age to develop knowledge of their linguistic environments, using a set of specific mechanisms that guide language development.
Infants have to be able to distinguish linguistic information from nonlinguistic stimuli: they attribute meaning and linguistic function to words and not to dog barks or telephone rings (Mehler and Christophe, 1995). By 4 months of age, infants clearly show a preference for listening to words over other sounds (Colombo and Bundy, 1983). And they can distinguish changes in language. For example, after being habituated to English sen- tences, infants detected the shift to a different language, such as Spanish; they did not register shifts to different English utterances (Bahrick and Pickens, 1988), which indicates that they noticed the novel Spanish utterances. Fig- ure 4.5 illustrates that American-born infants, at 2 months of age, start react- ing to English utterances significantly faster than they do to French utter- ances. Young infants learn to pay attention to the features of speech, such as intonation and rhythm, that help them obtain critical information about lan- guage and meaning. As they get older, they concentrate on utterances that share a structure that corresponds to their maternal language, and they ne- glect utterances that do not.
By 6 months of age, infants distinguish some of the properties that char- acterize the language of their immediate environment (Kuhl et al., 1992). Around 8-10 months of age, infants stop treating speech as consisting of mere sounds and begin to represent only the linguistically relevant contrasts (Mehler and Christophe, 1995). For example, Kuhl et al. (1992) have shown that the contrasts “ra” and “la” can be learned by very young English and Japanese babies alike, but later on only the contrast relevant to the mother
FIGURE 4.5 Reaction time to French and English sentences for 2- month-old infants. Mean latencies of initiation of a visual saccade in the direction of the sound for American 2-month-olds listening to French and English sentences. SOURCE: Adapted from Mehler and Christophe (1995:947). 2,500 2,400 2,300 2,200 2,100 2,000 English French 0 R eact ion t imes (msec )
language is retained as the other one drops out (e.g., “la” drops out for Japanese infants). Such studies illustrate that the learning environment is critical for determining what is learned even when the basic learning mecha- nisms do not vary.
Young infants are also predisposed to attend to the language spoken by others around them. They are attracted to human faces, and look especially often at the lips of the person speaking. They appear to expect certain types of coordination between mouth movements and speech. When shown vid- eos of people talking, infants can detect the differences between lip move- ments that are synchronized with the sounds and those that are not.
Young children also actively attempt to understand the meaning of the language that is spoken around them. Roger Brown (1958) discussed “The Original Word Game” that children play with parents. Successful participa- tion involves the child’s making inferences about what someone must mean by paying attention to the surrounding context. Parents of 1-year-olds re- port that their children understand much of what is said to them, although there is obviously a great deal of information that children really do not understand (Chapman, 1978). For example, Lewis and Freedle (1973) ana- lyzed the comprehension abilities of a 13-month-old child. When handed an apple while she was in her high chair and told “Eat the apple,” the child bit it. When handed an apple while playing in her playpen and told “Throw the apple,” the child threw it. Lewis and Freedle performed an experiment in order to test whether the child really understood words such as “eat” and “throw.” They handed the child an apple while she was in her high chair and asked her to “throw the apple.” The child bit it. Later, when the child was in her playpen she was handed an apple and told “eat the apple.” She threw it. The child’s strategy was basically to assume that she should “do what you usually do in this situation.” This sound strategy is frequently correct.
In everyday settings, young children have rich opportunities for learn- ing because they can use context to figure out what someone must mean by various sentence structures and words. Unless she was being tested by tricky experimenters, for example, the child discussed above could deter- mine the general meanings of “apple,” “eat,” and “throw.” Similarly, if a mother says “Get your shirt” while pointing to the only loose object (a shirt) on the rug, the child begins to understand the meaning of “get” and “shirt.” Language acquisition cannot take place in the absence of shared social and situational contexts because the latter provide information about the mean- ings of words and sentence structures (Chapman, 1978). The child uses meaning as a clue to language rather than language as a clue to meaning (MacNamara, 1972). Parents and other caregivers take into account both context and children’s emerging abilities as they help them extend their
competencies. The extremely important guiding role that caregivers have in children’s cognitive development is discussed further below.
Language development studies illustrate that children’s biological ca- pacities are set into motion by their environments. The biological underpin- nings enable children to become fluent in language by about age three, but if they are not in a language-using environment, they will not develop this capacity. Experience is important; but the opportunity to use the skills— practice—is also important. Janellen Huttenlocher, for example, has shown that language has to be practiced as an ongoing and active process and not merely passively observed by watching television (Huttenlocher, cited in
Newsweek, 1996).