The human brain is a powerful control centre. It is responsible for everything from our ability to breathe to our ability to be empathic. It is responsible for all skills and abilities, and language is no exception. Language is an exceptionally complicated, yet highly coordinated task. It is a cognitive skill that is both unique to humans and universal to all human cultures. Different brain structures are responsible for all parts of language production – including hearing spoken words, making sense of those words, producing a response, and executing that response.
So how does the brain do this? Many researchers have asked themselves the same question, and some of them have attempted to find the answer. Most research uses fMRI (functional magnetic resonance imaging) so that the areas of the brain that are working harder during different situations can be viewed. More specifically, some research has examined the brains of interpreters to better understand the skills involved in understanding and producing speech. Two well-studied areas that play a very significant role in language are two areas known as Wernicke’s and Broca’s.
Wernicke’s area, located in the temporal lobe of the left hemisphere, usually, plays a large role in understanding the incoming language information. It is here that the original language goes in and where you make sense of the meaning of the words and sentences. Whether translating or interpreting written or audible language, Wernicke’s area is responsible for transforming words into their meaning. Not only is this area responsible for language comprehension, but it is where we plan the what we want to say back. For interpreters, an extra step is involved during which language is switched, and the speed of which this happens is extremely fast. If this area is damaged, speech is created without content or meaning.
The next large brain area involved in language is called Broca’s area. Although the research is less clear on the role of Broca‘s area, it has been hypothesized that Broca’s area also is involved in language production and comprehension, including verbal working memory, syntax, grammar, and the motor movements responsible for speech. It is also associated with functions outside of language, including motor-related activities associated with hand movements, and sensorimotor learning and integration. Damage to the Broca’s area can disrupt language production, but nobody is quite sure exactly what specific language-related function is lost to cause that disruption. Thus, the Broca’s area plays a large part in interpretation.
To get more specific, researchers have looked at brain scans of interpreters in three different situations: listening to a sentence in one language, listening to and repeating a sentence in one language, and listening to a sentence in one of their languages and interpreting it into another of their languages. Broca’s area was lit up during all of these tasks. Interestingly, the caudate nucleus, an area of the brain responsible for learning and decision making, was the most engaged part of the brain during the latter task. This makes sense, because the caudate nucleus uses information learned from previous experiences and to make future decisions, and so it coordinates different parts of the brain to do this. These researchers hypothesize that interpretation requires various regions of the brain, not only the language centres, to be coordinated during the difficult task of interpretation. The caudate nucleus becomes more engaged during such a task because it has a huge role in facilitating this highly coordinated function.
In general, language is a multi-faceted cognitive skill that engages many areas of the brain, but most prominently Broca’s area and Wernicke’s areas. For those who work in interpretation, it has been found that many more areas of the brain are also engaged, because the ability to switch languages requires more coordination and abilities. This coordination is likely to be controlled by the caudate nucleus. It is safe to say, however, that much more research is required to be able to answer exactly what happens in our brain when language is interpreted.