Science of Language

Young children seem to acquire language with little effort but for many adults, learning a new language is not so easy. How is the brain involved in language learning?

There are many ways to learn a new language. Some people will sign up for a language course while others may set off abroad to learn from native speakers. For some adults it can be daunting and many will claim that they are just no good at languages. Others put it down to their age, and remember the ease with which they picked up language as children. So what does science have to say about the ability to learn language? Does it have a biological basis?

Credit: National Insititute of Health

Image of the brain showing Broca's and Wernicke's area, which are responsible for comprehension of written and spoken language and for speech articulation.

Learning a language as a child

Anyone that has watched a baby learn to talk will agree that it’s a remarkable feat. Most humans can speak one or more languages competently by the time they are five years old. “We are predisposed to learn language easily as infants,” explains Dr Sven Mattys, an expert in the psychology of language at the University of Bristol. “We are all born with a ticking clock, where we can easily learn language with a minimum of speech input.”

Two areas of the brain in the left cerebral cortex are responsible for language: Broca's area is thought to be where language is produced while language processing and comprehension takes place in Wernicke's area. But many scientists believe that children are born with an innate ability for picking up the principles and organisation common to all languages, such as word meanings, sentence structure and sounds.This early period of effortless language learning is called the ‘critical period’ and it lasts for about the first ten years of life.

So what happens after this crucial time period? Rare cases of feral children, who are raised by animals in the wild or deprived of human contact when they are very young, show that they are incapable of learning to speak if they are not exposed to language before puberty. Adults also find it increasingly difficult to learn a second language as they get older.