Language acquisition is a considerable achievement. It is estimated that the average child has acquired a vocabulary of some 14,000 – 15,000 words by the age of 6 (Clark, 1991), and by the age of 21/2 the average child has developed almost the full range of grammatical structures found in the adult language (McNeil, 1970). In contrast to Skinner’s (1957) theory of language acquisition, which held that children are ‘blank slates’ with regard to language, and attributed language development to reinforcement and conditioning, Chomsky (1957) argued that language is subserved by an innate, dedicated ‘language faculty’, which he termed the Language Acquisition Device (LAD).
Chomsky (1957) held that the language to which children is exposed is ‘degenerate’ and full of stops and starts, and therefore only the existence of an innate device for language learning could account for the speed and relative ease with which children learn the language around them, from a very limited and grammatically incorrect sample of language and without formal teaching. Furthermore, he held that the ‘language faculty’ is distinct from general intelligence.
The essay will begin by outlining the main tenets of Chomsky’s theory of language acquisition. It will then examine evidence that supports Chomsky’s theory and evidence that challenges it. In exploring the extent to which Chomsky’s theory can account for language developmentse issues, the essay seeks to highlight a number of potential limitations to
Furthermore, Principles and Parameters theory states that the properties (parameters) of language vary from language to language and therefore language acquisition is a process of setting the right parameters based on experience. For example, some languages (English and French) require subjects, whereas others (Spanish and Italian) do not. Therefore, the null subject parameter is set to ‘off’ in English and ‘on ‘ in Spanish (Chomsky, 1981). According to Chomsky, children have an in-built knowledge of the rules of language (linguistic universals). This is known as Universal Grammar, and helps children to extact rules from the speech they hear around them.
A large body of evidence supports the notion that children can deduce rules from the linguistic input they hear around them. Berko (1958), for example, found that children could add appropriate noun endings to a non-existent word, and thereby to something they had never heard of (e.g., wug wugs). Brown and Fraser (1963) proposed that children’s telegraphic speech could be regarded as grammatical in that it was correctly formed, omitting only a verb or inflection (e.g., chair broken). Specifically, Chomsky (1957, 199…, 1995, 2000) argues that the children show creativity in their use of language (i.e. they produce utterances they have never heard before, such as the frequently quoted “allgone sticky”, which suggests that children do not simply imitate the speech of adults.
In support of Chomsky’s theory, it has been suggested that in addition to exposure to poor primary linguistic data, a child’s poorly formed sentences are rarely corrected by adults, and therefore that children acquire language despite the absence of feedback as to which strings of words are not properly formed. This is known as the ‘no negative evidence problem’ or the ‘logical problem of language acquisition’. For example, using transcripts of naturalistic dialogue between three parents and their children, Brown and Hanlon (1970) found that the parents’ responses to their child’s incorrect grammar (whether utterances were well-formed or not) was contingent upon the actual meaning of what was being said rather than the correct or incorrect grammatical structure. Furthermore, Chomksy’s position is supported by evidence showing that children acquire – and even invent – language if exposure to language is minimal or absent (e.g. groups of deaf children who develop gestural systems to communicate with one another.
reinforcement, by initially reinforcing words that sound adult-like, and eventually only full and coherent sentences. However, using transcripts of naturalistic dialogue between three parents and their children, Brown and Hanlon (1970) found that the parents’ responses to their child’s incorrect grammar (whether utterances were well-formed or not) was contingent upon the actual meaning of what was being said rather than the correct or incorrect grammatical structure. This severely discredited the assumption that reinforcement can account for linguistic development. In addition, McNeill (1966) proposed that not enough feedback on grammar is given and children do not always respond. Furthermore, Braine (1971) suggested that the children of parents who are very corrective of their children’s grammar actually develop grammar more slowly than others. Indeed the notion that parents do not correct grammar would suggest that they are more likely to reinforce incorrect grammar than correct grammar (Slobin, 1979).
Bandura (1971), a social learning theorist, proposed the concept of ‘abstract modelling’ – the notion that children extract rules of language by analysing the language that they imitate. Bates et al (1982) supported this hypothesis, finding that children who imitate others seem to develop language more rapidly than those who do not. However, the causal direction of this association cannot be ascertained, and Whitehurst and Vasta (1975) found that imitation did not influence grammatical development. In addition, imitation cannot account for the phenomenon of overgeneralisation (foots – foots) nor for novel utterances such as the frequently quoted “All gone sticky” (Braine 1971), which are highly unlikely to have been spoken by an adult. Having looked at the role of reinforcement and imitation, the essay will now examine other aspects of the environment that are considered to contribute to the emergence of language.
There is substantial research evidence associating language stimulation and interaction with caregivers with children’s acquisition of language. For example, Clarke-Stewart (1973) found that children whose mothers talk to them more have a greater vocabulary, and it has been suggested that parents who talk more have children whose language development is more advanced (Hoff-Ginsberg, 1991; Wells and Robinson, 1982). The way in which adults speak to children is also believed to be a factor in promoting language development; i.e., research findings indicate that the use of ‘motherese’ or ‘child-directed speech’ – the special way in which adults talk to children, typically using short, simple sentences, exaggerated intonation, gestures and higher pitch – facilitates the development of language (Snow, 1977), though some studies challenge the theory (Newport, E.L, Gleitman H & Gleitman L.R., 1977) and the use of ‘motherese’, while almost universal, is culturally determined. Samoans, for example, reject the notion of child-centredness and do not alter their speech when talking to children.
In addition, the importance of the environment in interaction with the child is highlighted in social interaction theory. Bruner (1978) suggests that adults provide a ‘scaffold’ for the child, a theoretical framework known as a Linguistic Acquisition Support System (LASS) in which they facilitate language development by fine-tuning language to the child’s ability and by gradually providing less assistance as the child’s competence increases (e.g. by gradually requesting more information from the child during verbal exchanges). It is also believed that adults help children acquire language through routines known as ‘formats’ in which language is learned in context and by teaching children social conventions such as ‘thank you’. Having considered the role of nurture in language acquisition, the essay now focuses on the nativist perspective.
Clearly, language must have a biological basis. Firstly, language is species-specific, though some researchers clearly disagree. However, despite extensive attempts at teaching chimpanzees to use language via sign language, none has ever advanced beyond the rudimentary language skills of a two or three-year-old child. The human brain is specialised for language, for instance, it is known that Broca’s area and Wernicke’s area in the temporal lobe are the most relevant parts of the brain for language and language is lateralised in the left hemisphere in the vast majority of people.