Language Acquisition Device (LAD)

The linguist Noam Chomsky has argued that children are born with the innate ability to learn a language. Just how is that possible? He argues that it is due to a hypothetical 'tool' in the child's brain which he calls the Language Acquisition Device (LAD).Before we can examine the Language Acquisition Device, it's important to first understand the background of this idea.

The Nativist Theory

The concept of the LAD falls into a linguistic theory known as the nativist theory, or nativism. In terms of language acquisition, nativists believe that children are born with an innate ability to organise and comprehend the fundamental laws and structures of a language. Nativists believe this is why children can learn a native language so quickly.

Whereas behaviourist theorists (such as B. F Skinner) argue that children are born with minds that are 'blank slates' and learn a language by imitating their caregivers, nativist theorists argue that children are born with an inbuilt ability to learn a language.

In the nature vs nurture debate, which has been ongoing since 1869, nativist theorists are typically team nature.

For many years, behaviourist theorists were winning the language acquisition debate, mainly due to a lack of scientific evidence behind the nativist theory. However, all that changed with the arrival of Noam Chomsky. Chomsky is perhaps the most influential nativist theorist and helped revolutionise the field of linguistics in the 1950s and 60s by treating language as a uniquely human, biologically based, cognitive ability.

Noam Chomsky

Noam Chomsky (1928-present), an American linguist and cognitive scientist, is considered the pioneer of the nativist theory. In the 1950s, Chomsky rejected the behaviourist theory (which states that children learn a language by imitating adults) and, instead, suggested that children are 'hard-wired' to learn a language from birth. He came to this conclusion after he noticed that children were able to form syntactically correct sentences (e.g. subject + verb + object) despite receiving impoverished language input (baby talk), and not being taught how to do so.

In the 1960s, Chomsky went on to propose the concept of the language acquisition device (LAD for short), a hypothetical 'tool' that helps children learn a language. Chomsky suggested that the LAD gives children an innate ability to understand the fundamental rules of language.

What is the Language Acquisition Device?

Chomsky proposed the concept of the LAD to help explain how children are able to use the basic structures of language, even though they rarely receive instruction on how to speak their native language. He originally suggested that the LAD contained specific knowledge that is key to understanding the rules of language; however, he went on to adapt his theory and now suggests the LAD works more like a decoding mechanism.

Chomsky stated that the LAD is a uniquely human trait and cannot be found in animals, which helps explain why it is only humans that can communicate through language. Although some apes can communicate via signs and images, they are unable to grasp the complexities of grammar and syntax.

It's important to remember that the LAD is a hypothetical tool, and there is no physical language device in our brains!

How does the Language Acquisition Device work?

Chomsky proposed that the Language Acquisition Device is a biologically based hypothetical mechanism, which helps children decode and implement the general principles of universal grammar. As previously mentioned, the LAD isn't language specific. Once the child hears an adult speaking a language, the LAD is triggered, and it will help the child acquire that specific language.

Universal Grammar

Chomsky does not believe that a child from England is born with the innate ability to learn English, or that a child from Japan has a LAD containing Japanese vocabulary. Instead, he suggests that all human languages share many of the same common grammar principles.

For example, most languages:

• Differentiate between verbs and nouns

• Have a way of talking about the past and present tense

• Have a way of asking questions

• Have a counting system

According to Universal Grammar theory, the basic grammatical structures of language are already encoded in the human brain at birth. It is a child’s environment that will determine which language they will learn.

So, let's break down how the LAD supposedly works:

Virtuous errors

When children are first learning a language, they will, of course, make mistakes. These mistakes can be very informative as to how children learn. For example, children have an unconscious ability to recognise the past tense and will begin to associate words ending with a /d/ /t/ or /id/ sound with the past. Chomsky suggests this is why children make ‘virtuous errors’ such as, ‘I goed’ rather than ‘I went’ when first learning a language. Nobody taught them to say ‘I goed’; they figured that out for themselves. To Chomsky, these virtuous errors suggest that children are born with the subconscious ability to work out the grammatical rules of language.

The Poverty of Stimulus

In the 1960s, Chomsky rejected the behaviourist theory because children receive ‘impoverished language input’ (baby talk) when growing up. He questioned how children could demonstrate signs of learning grammar before being exposed to sufficient linguistic input from their caregivers.

The poverty of stimulus argument states that children are not exposed to enough linguistic data in their environment to learn every feature of the language. Chomsky suggested that the human brain must have evolved to contain certain linguistic information from birth, which helps children figure out the basic structures of language.

Critiques of the LAD

It is important to understand that other linguists hold opposing views of the LAD. Criticism of LAD mainly come from linguists who believe in the behaviourist theory, in particular these days from a branch of linguistics called 'connectionism'. Behaviourist theories are unlike nativist theories, as they argue that children learn language through imitating the adults around them. This theory supports nurture over nature.

Behaviourists argue that there is not enough scientific evidence to support the existence of a language acquisition device. For example, we do not know where the LAD is located in the brain. For this reason, many linguists reject this theory.