Language and the Mind

The last chapter turns inward. Chapters 2 to 6 described the structure of language and Chapters 7 to 9 its use, change and variation. But all of it lives in people's heads. How does a child, with no lessons, end up with the whole system? Why is a second language so much harder to learn as an adult? And where in the brain is language? This area is called psycholinguistics (the mind) and neurolinguistics (the brain).

First-Language Acquisition

Children in every culture follow roughly the same path, at roughly the same ages, without being taught:

Babies are born able to tell apart the sounds of every language, and over the first year they tune in to the phonemes of their own (Chapter 3), losing the ability to hear distinctions that don't matter in it. Deaf children of signing parents babble with their hands, on the same schedule.

Children Don't Just Copy

A key finding is that children build rules, and then apply them too widely. A child who says goed, foots or I runned has not heard those forms, because adults don't say them. They have worked out the regular past-tense and plural rules (Chapter 4) and applied them to irregular words. Later the child learns the exceptions and the forms correct themselves. This is overgeneralisation, and it is good evidence that learning is rule-building and not memorising. The "wug test" in Chapter 3, where children add the plural to a nonsense word, shows the same thing.

Adults do not need to correct children for this to work. Parents mostly respond to the meaning, not the grammar, and children still reach the adult system. Explaining how they manage it is a major debate. Noam Chomsky argued that the input is too limited to explain the result (the "poverty of the stimulus"), so humans must be born with an inherited language faculty, often called universal grammar. Other researchers argue that children are very good at finding patterns in large amounts of speech, and that no special language faculty is needed. The question is still open.

Is There a Critical Period?

The critical period hypothesis says that there is an age window, ending somewhere around puberty, after which a first language can no longer be fully acquired. The evidence is mixed and sad. The best-known case, "Genie", was a girl kept in isolation in California until the age of thirteen. She learned many words but never mastered grammar, though her case is hard to interpret because of the abuse she suffered. Stronger evidence comes from deaf children: those who first learn a sign language late in childhood end up less fluent than those who learn it from birth. In Nicaragua in the 1980s, deaf children brought together in new schools created a new sign language, Nicaraguan Sign Language, and each younger group of children made it more regular and complex. This is language arising from scratch.

Learning a Second Language

Adults and older children usually learn a second language more slowly and rarely sound native, even though they are quicker at the start because they can use study and a first language. The learner's speech is a system of its own, called an interlanguage, which sits between the first language and the target language and gradually moves toward the target. Much of it comes from transfer, carrying over the first language's patterns:

Errors of this kind are not signs of a poor learner. They are predictable and tell you which parts of the new language are furthest from the old one, which is a practical use of everything you learned in Chapters 2 to 5. What helps most is a great deal of meaningful input, practice using the language to communicate, and motivation. Nobody has found a way of skipping the time.

Language in the Brain

Our knowledge of where language lives in the brain began with people who suffered damage to it. Two areas in the left hemisphere (the dominant side for language in most right-handed people and many left-handed ones) are named after the doctors who described them:

A simple picture is that Broca's area is for producing speech and Wernicke's for understanding it, but this is only a first approximation. Modern brain scans show that language uses a network over several regions, and that the two areas are part of a larger system. Sign languages use the same left-hemisphere areas as spoken ones, which supports the view that language is a system of the mind, not just of the voice (Chapter 1).

Bilingualism

A bilingual person is not two monolinguals in one head. Both languages are active at once, and the speaker switches between them with practice (Chapter 9). Studies have claimed benefits for attention and mental flexibility, and some evidence that bilingualism delays the symptoms of dementia, but the size of these effects is debated. What is clear is that bilingual children develop language normally, and that being bilingual is not a disadvantage. Most of the world's people use more than one language.

Hands-On Exercises

Course Complete: What You Have Covered

You have now been through every core area of linguistics, with examples from English, German, French, Hungarian, Japanese, Scots and Esperanto. The ten chapters form a map of the field:

Where to Go Next

Several follow-up courses take one of these areas much further: Phonetics and the IPA (Chapters 2 and 3), Historical Linguistics and Language Families (Chapter 8), Sociolinguistics: Language, Dialect and Society (Chapter 9), Writing Systems of the World and Computational Linguistics. The constructed-languages courses, beginning with Klingon Grammar 1, apply this course's tools to languages built on purpose. And any language course on this site is now easier to read: you can name what a table of endings is doing, hear why a sound is hard, and see why a phrase means more than its words.