Key Concepts in Child Language Acquisition
Language Acquisition Device (LAD)
Proposed by Chomsky (1959), the Language Acquisition Device (LAD) refers to an innate grammatical structure believed to underlie all human languages. It enables children, once they acquire a sufficient vocabulary, to combine words into novel yet grammatically consistent utterances and to understand the meaning of language quickly. Children are not explicitly taught language rules; instead, this ability develops naturally with mere exposure to a language environment.
Overregularization in Child Language
Overregularization is the process where children inappropriately extend regular morphological rules to irregular words, for example, saying “goed” instead of “went” or “runned” instead of “ran”. These occurrences are frequent in the speech of three-year-olds. Since children do not typically hear mature English speakers use forms like “goed” or “runned”, these mistakes indicate that they are actively developing productive grammatical rules from an early age.
Calquing: Borrowing Language Structures
A calque is a type of loanword where a phrase is borrowed from another language, but each element of the phrase is translated literally into the target language (e.g., English “weekend” becoming French “fin de semaine”). This process respects the syntactical structures of the target language. Calquing avoids the direct use of foreign words and can contribute to the richness of the target language. It can occur at various linguistic levels.
Additive vs. Subtractive Bilingualism
Bilingualism is the ability to communicate alternately in two languages. If becoming bilingual helps learners develop positive attitudes toward both languages and themselves, it is called additive bilingualism. Conversely, if learners develop negative attitudes towards their first language (L1) while acquiring a second language (L2), it is termed subtractive bilingualism.
Acquiring Negation: Developmental Stages
Mastering negation involves a complex interplay of grammatical, semantic, and input factors, leading to distinct developmental patterns. Three semantic types of negation typically appear in children’s speech in the following order:
- Non-existence: The child remarks on the absence of something (e.g., “no cookie”).
- Rejection: The child expresses opposition to something (e.g., “no take bath”).
- Denial: The child denies the truthfulness of a statement (e.g., “that no my kitty”).
First Word Acquisition Processes
Fast Mapping
Fast mapping helps explain how young children rapidly build a large vocabulary. In this process, a child quickly connects a new word with an underlying concept after only a brief encounter. This initial understanding of the new word and concept is refined through subsequent exposures.
Bootstrapping
In bootstrapping, children decode word meanings by using existing knowledge (syntactic, semantic, or phonological) to figure out new information. For example, they might use the grammatical structure of a sentence to infer the meaning of an unknown verb.
Motherese (Child-Directed Speech)
Motherese, or child-directed speech, refers to the specific way caregivers, especially mothers, talk to young children to facilitate language learning. Key adaptations include:
- Expansions: Restating the child’s utterance in a more complete grammatical form (e.g., Child: “Doggie run.” Parent: “Yes, the doggie is running.”).
- Recasts: Rephrasing the child’s utterance, often correcting errors implicitly (e.g., Child: “I goed store.” Parent: “Oh, you went to the store?”).
- Other features: Slower pace, exaggerated intonation, avoidance of contracted forms, pauses, absence of filler words (like “uh” or “um”), and simplification of semantics and syntax.
Mean Length of Utterance (MLU)
Mean Length of Utterance (MLU) measures the average number of morphemes (or sometimes words) a child produces in their utterances at a particular stage. MLU is often used to track grammatical development and can be broadly divided into stages, such as the one-word stage, the two-word stage, and the stage of complex speech.
Critical vs. Sensitive Periods in Acquisition
The Critical Period Hypothesis, proposed by Lenneberg, suggests that language acquisition must occur within a specific developmental window (typically before puberty) when the brain is optimally receptive. During this time, language functions become lateralized and specialized. If language exposure is delayed beyond this period, acquiring language becomes significantly more difficult, if not impossible. Studies of children deprived of early language input support this idea.
The concept of a Sensitive Period offers a less rigid alternative. Researchers like Snow and Hoefnagel-Höhle observed that older learners often acquire aspects of a second language faster than younger children. They argue that factors such as motivation, learning strategies, and social context play significant roles alongside biological maturation. People of various ages can learn languages effectively, especially when motivated by necessity. Older children may progress faster due to more developed cognitive and learning strategies.
Early Phonological Strategies
Children often use systematic strategies to simplify pronunciation as they learn to speak. Common phonological strategies include:
- Reduplication: Repeating a syllable, often the initial one, in a multisyllabic word (e.g., “water” becomes “wawa”, “cookie” becomes “kiki”).
- Deletion of sounds: Omitting unstressed syllables or final consonants (e.g., “banana” becomes “nana”, “ball” becomes “ba”).
- Replacement of difficult sounds: Substituting easier sounds for more difficult ones. This can involve replacing fricatives (like /s/) with stops (like /t/), liquids (/l/, /r/) with glides (/w/, /j/), or simplifying consonant clusters (e.g., “sea” becomes “tea”, “ready” becomes “weddy”, “apple” becomes “appo”, “shop” becomes “sop”). Consonants produced at the front of the mouth are often preferred.
It’s important to remember that a child’s first words are linked to their perception and mental representation of the world.
Early Semantic Strategies in Children
As children learn word meanings, they employ various strategies:
- Identity: Using the correct label for an object or concept (e.g., calling a dog “dog”).
- Partial overlap: Referring to something by a related characteristic, often the sound it makes (e.g., calling a dog “woof-woof”, or a train “choo-choo”).
- Mismatches: Using an incorrect word to refer to something (e.g., calling a horse parade [cabalgata] a waterfall [catarata] – *Note: This specific example might depend on language context*).
- Underextension: Using a general word for only a specific subset of its category (e.g., using “dog” only for the family pet but not other dogs, or “person” only for adults).
- Overextension: Applying a word to a wider range of objects or concepts than is appropriate; overusing the principle of extendibility (e.g., calling all four-legged animals “dog”, or all flying things “bird”).
Late Semantic Strategies in Children
As vocabulary grows, children develop more sophisticated semantic strategies:
- Word Coinages: Creating new words, often based on existing ones, starting around age two. Early strategies involve compounding (e.g., “plant-man” for “gardener”) or deriving verbs from nouns (e.g., “needle something” for “mend something”).
- Metaphors: Children begin using metaphors, initially based on sensory comparisons (e.g., “clouds are pillows”, “leaves are dancers”). Later, they can produce more abstract metaphors (e.g., “a fire engine in my tummy” for a stomachache).
Language Making Capacity (LMC)
Proposed by Slobin, the Language Making Capacity (LMC) refers to a set of innate cognitive and perceptual strategies or operating principles that children use to analyze linguistic input. These principles help them discover grammatical regularities and build the grammar of their language.