Theories of Language Acquisition

How do children acquire language? This seemingly simple question has generated one of the most fascinating and enduring debates in linguistics and psychology. Over the past century, four major theoretical perspectives have emerged, each offering a different explanation for how children move from babbling infants to fluent speakers. Understanding these theories is essential for AQA A-Level English Language, as they underpin every aspect of child language acquisition (CLA) study.

The Nativist Approach

The nativist perspective argues that the ability to acquire language is innate — that is, humans are born with a biological predisposition for language. The most influential nativist is Noam Chomsky (1957, 1965), whose work revolutionised our understanding of language acquisition.

Chomsky's Language Acquisition Device (LAD)

Chomsky proposed that all children are born with a Language Acquisition Device (LAD) — an innate mental mechanism dedicated to language learning. The LAD allows children to:

Analyse the language they hear in their environment
Extract grammatical rules from that input
Generate and understand an infinite number of novel sentences

Key Definition: Language Acquisition Device (LAD) — a hypothetical innate mechanism proposed by Chomsky that enables children to acquire the grammatical rules of any human language they are exposed to.

Universal Grammar

Chomsky further proposed that all human languages share a set of underlying structural principles called Universal Grammar (UG). According to this view, children are born with knowledge of these universal principles, and exposure to a specific language simply "sets the parameters" for that language.

Concept	Explanation
LAD	An innate biological mechanism for language acquisition
Universal Grammar	A set of structural rules common to all human languages
Parameter setting	Exposure to a specific language triggers the correct grammatical settings
Poverty of the stimulus	The language input children receive is too impoverished to explain the complexity of what they learn

The Poverty of the Stimulus Argument

Chomsky's poverty of the stimulus argument (1980) is central to nativist thinking. He argued that the language input children hear is:

Full of errors, false starts, and incomplete sentences
Insufficient to explain the complex grammatical rules children acquire
Not accompanied by explicit grammar teaching

Despite this impoverished input, children reliably acquire complex grammar — suggesting that innate knowledge must be supplementing the input they receive.

Evidence for Nativism

All children acquire language in a similar sequence, regardless of culture or language
Children produce sentences they have never heard before, demonstrating creativity rather than imitation
Children make virtuous errors (e.g. "I goed", "mouses") that show they are applying rules rather than copying
There is evidence for a critical period for language acquisition (Lenneberg, 1967) — if children are not exposed to language before puberty, they struggle to acquire it fully (e.g. the case of Genie, Curtiss, 1977)

Criticisms of Nativism

The LAD is a hypothetical construct — no specific brain structure has been identified as the LAD
Nativism underestimates the role of input — children's language development is affected by the quality and quantity of the language they hear
It is difficult to test empirically — Universal Grammar remains controversial among linguists
It cannot explain variation in the rate and style of language development between children

The Behaviourist Approach

The behaviourist approach, most associated with B.F. Skinner (1957), argues that language is learned through the same mechanisms as any other behaviour: imitation, reinforcement, and conditioning.

Skinner's Operant Conditioning

In his book Verbal Behavior (1957), Skinner argued that children learn language through operant conditioning:

Imitation — Children imitate the language they hear around them
Positive reinforcement — When a child produces a correct or comprehensible utterance, caregivers respond with praise, attention, or by fulfilling the child's request
Negative reinforcement — Incorrect utterances are corrected or ignored, reducing their frequency
Shaping — Caregivers gradually shape children's language towards adult forms by selectively reinforcing closer and closer approximations

Key Definition: Operant conditioning — a learning process in which behaviour is strengthened or weakened by its consequences (reinforcement or punishment). Skinner applied this to language learning, arguing that children's utterances are shaped by caregiver responses.

Mechanism	Example
Imitation	Child hears "doggy" and repeats "doggy"
Positive reinforcement	Child says "milk" and mother gives milk, reinforcing the word
Correction	Child says "I goed" and parent says "No, you went"
Shaping	Baby babbles "ma-ma-ma", parent responds enthusiastically, baby learns "mama"

Criticisms of Behaviourism

Chomsky's (1959) review of Skinner's Verbal Behavior was devastating:

Children produce novel utterances they have never heard — this cannot be explained by imitation alone
Children make systematic overgeneralisations (e.g. "sheeps", "runned") that they could not have learned from adult speech
Parents rarely correct grammar explicitly — research by Brown, Cazden, and Bellugi (1969) showed that parents respond to the truth value of children's utterances rather than their grammatical accuracy
Language acquisition follows a universal sequence regardless of individual experience, suggesting an innate component
The speed of acquisition is too fast to be explained by reinforcement alone — children acquire thousands of words and complex grammar within a few years

The Cognitive Approach

The cognitive approach, primarily associated with Jean Piaget (1926, 1952), argues that language development is dependent on and driven by cognitive development. Language is not a separate, innate module but rather one aspect of a child's broader intellectual development.

Piaget's Stages and Language

Piaget proposed that children pass through a series of cognitive stages, and that language development is linked to progress through these stages:

Piaget's Stage	Age (approx.)	Cognitive Achievement	Language Implication
Sensorimotor	0–2 years	Object permanence; understanding the world through senses and actions	First words emerge as children understand that objects exist independently; language is egocentric
Pre-operational	2–7 years	Symbolic thinking; egocentrism; animism	Rapid vocabulary growth; use of symbols (words) to represent objects; language is self-centred
Concrete operational	7–11 years	Conservation; logical thinking about concrete objects	Language becomes more logical and less egocentric; metalinguistic awareness develops
Formal operational	11+ years	Abstract reasoning; hypothetical thinking	Abstract language; ability to discuss hypothetical scenarios and complex ideas

Object Permanence and Language

Piaget argued that a child must first develop object permanence — the understanding that objects continue to exist even when they cannot be seen — before they can use words to refer to absent objects. This typically develops around 8–12 months, shortly before the first words appear.

Key Definition: Object permanence — the understanding that objects continue to exist even when they are not directly perceived. Piaget argued this cognitive milestone is a prerequisite for language, as words are symbols that stand for things not necessarily present.

Evidence and Evaluation

There is a correlation between cognitive milestones and language milestones — e.g. object permanence and first words
However, correlation does not prove causation — cognitive development may not cause language development
Some children with severe cognitive impairments can still acquire relatively complex language (e.g. Williams syndrome), challenging Piaget's claim that cognition drives language
Piaget underestimates the role of social interaction in language development

The Social Interactionist Approach

The social interactionist approach argues that language is acquired through social interaction with more experienced language users. Key figures include Jerome Bruner (1983) and Lev Vygotsky (1978).

Bruner's Language Acquisition Support System (LASS)

Bruner (1983) proposed the concept of the Language Acquisition Support System (LASS) — the idea that caregivers provide a supportive framework that helps children acquire language. Bruner saw the LASS as a complement to Chomsky's LAD: children may have an innate capacity for language, but they need social support to activate and develop it.

Key features of the LASS include:

Scaffolding — caregivers provide structured support that is gradually withdrawn as the child becomes more competent
Formats and routines — repeated, predictable interactions (e.g. peek-a-boo, reading rituals) that provide a framework for language learning
Joint attention — caregiver and child focus on the same object or event, facilitating word learning

Key Definition: Language Acquisition Support System (LASS) — Bruner's term for the supportive framework provided by caregivers that helps children learn language through structured social interaction, scaffolding, and routine formats.

Vygotsky's Zone of Proximal Development (ZPD)

Vygotsky (1978) introduced the concept of the Zone of Proximal Development (ZPD) — the difference between what a child can do alone and what they can achieve with the help of a more knowledgeable other (MKO). Applied to language:

Children can produce more complex language with adult support than they can independently
Caregivers intuitively pitch their language just above the child's current level
Through supported interaction, children gradually internalise more complex language structures

Concept	Theorist	Explanation
LASS	Bruner (1983)	Caregivers provide a support system that complements the child's innate ability
Scaffolding	Bruner (1983)	Structured support that is gradually removed as the child gains competence
ZPD	Vygotsky (1978)	The gap between independent ability and ability with support from a more knowledgeable other
MKO	Vygotsky (1978)	A more experienced language user who supports the child's development

Evidence for Social Interactionism

Children who receive more interaction tend to develop language faster
Child-directed speech (CDS) — the modified way adults speak to children — suggests caregivers intuitively support language learning
Studies of isolated children (e.g. Genie) show that lack of social interaction severely impairs language development
Cross-cultural research shows that the form of interaction varies but all cultures provide some support for language learning

Criticisms of Social Interactionism

Some cultures provide very little direct interaction with young children (Ochs and Schieffelin, 1984), yet children still acquire language — challenging the claim that interaction is essential
It is difficult to disentangle the effects of social interaction from innate ability
The approach may overemphasise the role of caregivers and underestimate the child's own active contribution to language learning

Comparing the Four Approaches

Feature	Nativist	Behaviourist	Cognitive	Social Interactionist
Key figure	Chomsky	Skinner	Piaget	Bruner, Vygotsky
Nature or nurture?	Nature	Nurture	Nature and nurture	Nature and nurture
Key mechanism	LAD / Universal Grammar	Imitation and reinforcement	Cognitive development	Social interaction and scaffolding
Role of input	Triggers parameter setting	Source of all learning	Secondary to cognition	Essential — provides scaffolding
Strengths	Explains universals and creativity	Explains role of environment	Links language to cognition	Explains role of caregivers
Weaknesses	LAD is hypothetical	Cannot explain creativity or overgeneralisations	Underestimates social role	Some cultures offer minimal interaction

Exam Tips

Always evaluate — do not just describe theories. Show that you can assess their strengths and limitations.
Use specific evidence — reference named researchers and dated studies (e.g. Chomsky, 1965; Brown, Cazden and Bellugi, 1969).
Link theories to data — when analysing child language data, explain which theory best accounts for the features you observe.
Avoid presenting theories as mutually exclusive — most modern linguists accept that language acquisition involves a combination of innate ability, cognitive development, and social interaction.
Remember key terms — LAD, LASS, ZPD, poverty of the stimulus, operant conditioning, scaffolding, and object permanence are all essential vocabulary.