Theories of Foreign Language Acquisition

 Why Do We Learn Languages the Way We Do?

Imagine someone like Matthew Youlden, who speaks nine languages fluently and understands even more. Switching between languages effortlessly is like a chameleon changing colors—fluid and natural. But how do people really learn a second language? What happens inside the brain? And how can knowing this help you, as a future bilingual teacher, support your students better?

In this unit, we’ll explore the main theories that explain how people acquire or learn a second language (L2). You’ll hear stories, share your own experiences, and see the science behind language learning. The goal is to understand the big picture, so you can apply these ideas practically and confidently in your classroom.

Sharing Your Own Story: A Psychotherapy Session for Language Learners

Before diving into theories, think about your own journey with an L2.

• When did you feel you really made progress?
• How did it feel talking to strangers at first? And how about later?
• Can you remember moments shopping, working, or hanging out with friends where your language skills surprised you?

These personal stories connect theory with reality—they remind us that learning a language is a deeply human experience, full of challenges and triumphs.

Why Are There So Many Theories?

The truth is, language acquisition is complex. Researchers look at different angles: some focus on behaviour, others on the brain, and some on social interaction. Because of this, it’s hard to find one single explanation that fits every learner.

Here, we’ll review five major theories, each offering valuable insights:

• Conductism (Empiricist Theory)
• Innatism
• Cognitivism
• Interactionism
• Environmental Theories

A. Conductism (Behaviourism)

This is one of the oldest theories, based on the idea that language learning happens through reinforcement—basically, rewards and punishments. B.F. Skinner (1957) argued that kids learn to speak because their caregivers praise or correct them. For example, when a baby says "milk" and the parent responds positively by giving milk, the baby is encouraged to say it again.

Think about how often you’ve praised a student for trying to speak, even if they made mistakes. That encouragement is a kind of positive reinforcement.

Here are some key ideas:

• Stimulus > Response > Reinforcement: A behaviour happens because it was rewarded or avoided because it was punished.
• Operant Conditioning: This means behaviours followed by pleasant results are repeated; those followed by unpleasant results tend to disappear (Thorndike, 1911).
• Reinforcement can be positive (giving a treat), negative (removing a chore), or punishment (a frown or correction).

But the truth is, language isn’t only about repeating what we hear. Sometimes we create sentences we’ve never heard before. This is where other theories step in.

B. Innatism

Noam Chomsky revolutionized language learning theories by suggesting that we are born ready to learn language. He introduced the idea of a Language Acquisition Device (LAD)—an inborn mental system that helps us pick up language naturally (Chomsky, 1965).

Here’s what this means in simple terms:

• Instead of being a blank slate (tabula rasa), every human brain comes pre-wired with universal grammar rules shared by all languages.
• Children don’t just imitate—they create new sentences using these rules, showing the brain’s creative power.
• This explains why kids can say things they’ve never heard before, like “goed” instead of “went.” It’s their brain applying internal grammar rules.

Chomsky’s ideas led to concepts like Transformational Grammar, a system that generates possible sentences from basic rules.

Krashen’s Monitor Model (A Development from Innatism)

Stephen Krashen (1981) took these ideas further, explaining language acquisition as mostly unconscious—like picking up a language naturally through exposure, not just study. He introduced several important points:

• Acquisition vs. Learning: Acquisition happens naturally and without effort, while learning is conscious and intentional.
• Input Hypothesis (i+1): We learn best when the language input is just a little beyond our current level. For example, if you know simple sentences, hearing slightly more complex ones helps you grow.
• Affective Filter: Feelings matter! Low anxiety, high motivation, and confidence open the door to better language learning. Stress or fear, on the other hand, block it.
• Natural Order Hypothesis: We acquire grammar in a predictable sequence, no matter our native language. For example, negations like “not” come in stages.

C. Cognitivism

What happens inside the brain matters. Cognitivism connects language learning with broader mental skills like memory, attention, and problem-solving (Piaget, 1952). It’s not just about language alone but how we think.

For example:

• When you learn a new language, at first you consciously focus on grammar and vocabulary (controlled processing). It takes effort.
• Over time, many skills become automatic—like recognizing words or constructing sentences without thinking (automatic processing) (McLaughlin, 1987).

Cognitivism highlights stages learners go through:

1. Cognitive Stage: Conscious effort and study.
2. Associative Stage: Making connections and using strategies.
3. Autonomous Stage: Fluent, automatic use of language.

This helps explain why students struggle initially but improve with practice and exposure.

D. Interactionism

What happens when you talk with others? Interactionism says that language is learned through social interaction—it’s not just in the head, but in the real world.

Lev Vygotsky (1978) introduced the idea of the Zone of Proximal Development (ZPD): this is the “sweet spot” where a learner can do something new with the help of a more knowledgeable person—like a teacher, peer, or native speaker.

Think of it this way:

• A child watches people talk, then tries it themselves.
• Social communication comes before full understanding.
• The way people talk to learners—modified input or “foreigner talk”—helps learners catch on. This might mean speaking slowly, using simple sentences, or avoiding idioms.

Examples of modified input:

• Speaking clearly and slowly.
• Using shorter, simpler sentences.
• Choosing familiar topics like shopping or weather.

This theory reminds us how vital real conversation is—and why classroom interaction, peer collaboration, and authentic communication matter so much.

E. Environmental Theories

Finally, environment shapes language learning in huge ways. Schumann’s Acculturation Model (1978) focuses on the social and psychological distance between language groups.

Here’s what matters:

• If two groups share equal social status, it’s easier to learn the second language.
• The more people interact socially and culturally, the better the language acquisition.
• Positive attitudes and motivation make a big difference.
• The longer someone stays immersed in the language environment, the better their language gets.

But cultural differences can also cause “language shock” or “culture shock,” making learning harder at first. Imagine moving to a new country where customs, food, and social norms feel strange—this discomfort can block learning unless addressed with support and patience.

Quick Review: Questions & Answers

• Which theory says language learning happens by reinforcement? Conductism (Skinner)
• Which theory claims we’re born with language ability? Innatism (Chomsky)
• What can affective filters do according to Krashen? They can block or allow language acquisition depending on emotions.
• Is language acquisition conscious or unconscious? Acquisition is unconscious; learning is conscious.
• Do automatic language processes require attention? No, only controlled processes do.
• What is “foreigner talk”? Modified language input by native speakers to help beginners understand.

Final Thoughts

Understanding these theories gives you powerful tools. You’ll see that teaching an L2 isn’t about only drilling grammar or vocabulary. It’s about creating a rich environment—socially, cognitively, and emotionally—that encourages learners to feel confident, supported, and motivated.

Remember Matthew Youlden’s ability to switch effortlessly between languages? Behind that skill are all these complex processes working together—reinforcement, innate structures, cognition, social interaction, and environment. Your students’ journeys will be unique, but these theories offer a roadmap to guide and empower them.

References

Chomsky, N. (1965). Aspects of the theory of syntax. MIT Press.

Krashen, S. D. (1981). Second language acquisition and second language learning. Pergamon Press.

McLaughlin, B. (1987). Theories of second-language learning. Edward Arnold.

Piaget, J. (1952). The origins of intelligence in children. International Universities Press.

Schumann, J. H. (1978). The acculturation model for second-language acquisition. In R. C. Gingras (Ed.), Second language acquisition and foreign language teaching (pp. 27–50). Center for Applied Linguistics.

Skinner, B. F. (1957). Verbal behavior. Appleton-Century-Crofts.

Vygotsky, L. S. (1978). Mind in society: The development of higher psychological processes. Harvard University Press.