How the Brain Makes Way for a Second Language
"Studies involving sophisticated brain imaging technologies called functional magnetic resonance imaging, fMRI, have also revealed some intriguing patterns in the way our brains process first and second languages.
Joy Hirsch and her colleagues at Cornell University used fMRI to determine how multiple languages are represented in the human brain. They found that native and second languages are spatially separated in Broca's area, which is a region in the frontal lobe of the brain that is responsible for the motor parts of language-movement of the mouth, tongue, and palate. In contrast, the two languages show very little separation in the activation of Wernicke's area, an area of the brain in the posterior part of the temporal lobe, which is responsible for comprehension of language.
The fMRI studies suggest that the difficulty adult learners of a second language may have is not with understanding the words of the second language, but with the motor skills of forming the words with the mouth and tongue. This may explain why learners of a second language can oftentimes comprehend a question asked in the new language, but are not always able to form a quick response.
Thus, for adult English language learners, techniques that emphasize speaking may be more successful than methods that focus more on reading and listening. For example, rather than lecturing to a class about vocabulary and grammar, an instructor perhaps should encourage her adult students to have conversations in English, or to act out short skits incorporating the day's lesson, which would more closely link the students' abilities to understand and speak the new language. Speaking would thus equal understanding.
The Cornell researchers also studied the brains of people who were bilingual from a very early age. Presumably, this group of people is able to speak the two languages as easily as they can comprehend both languages spoken to them. The researchers found that these subjects showed no spatial separation in either Broca's or Wernicke's areas for the two languages, indicating that in terms of brain activation at least, the same regions of the brain controlled their ability to process both languages.
The idea that second languages learned early in childhood are not separately processed in the brain is supported by fMRI studies of brain development in children. Researchers at UCLA report that the language areas of the brain seem to go through the most dynamic period of growth between the ages of 6 and 13. In contrast to the "first three years" idea of child development that has received so much press in the past few years, the UCLA study instead suggests that the elementary and middle school years are the biologically most advantageous times for acquisition of a second language.
These various neuroscience studies tell us that the brain is a remarkably plastic entity. A combination of listening and vocalization seems to be the most biologically advantageous method of acquiring a second language for both adults and children. Incorporating what we know about the way the brain processes language into the way languages are taught will benefit not only students who want to learn English, but also all those who wish to extend their linguistic range."