Two main theories work to explain language development. Nativists argue that humans are biologically programmed to gain knowledge, but interactionists emphasise the environment.

Chomsky’s Theory

Noam Chomsky described innate language development using the Language Acquisition Device (LAD). Universal rules are used to construct proper sentences, and there is a genetic predisposition for language and grammar development. Children know it in advance and so acquire it quickly.

Surface structure rules describe grammatical structure of spoken language, whereas deep structure rules enable the production of grammatically correct, written sentences.

Evidence for Chomsky’s theory include:

• children master language faster than other abilities

• they develop correct grammar without being corrected

• deep structures are the same in all languages

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Limitations of Chomsky’s theory includes:

• the theory paid little attention to the child’s social background

• it places too much emphasis on innate predisposition rather than the environment

• the concept is abstract and cannot be scientifically tested

Bruner’s Theory

Jerome Bruner proposed language development through environmental influence. The Language Acquisition Support System (LASS) describes how parent interaction guides and supports language. He proposed that the child learns the language that they are surrounded by. The LASS is dependent on its interaction with the LAD, and can explain different rates of development.

The components of the LASS include:

1. scaffolding is the instructional component where parents encourage routines which rewards ability development, including new meanings, and the rate and complexity of speech.

2. referencing directs the child’s attention so that language is associated with different objects.

3. routines include both scaffolding and referencing work together to form the LASS. -

   referencing is via eye contact, pointing, books and association, and scaffolding is via encouragement and becoming more specific with reinforcements.