Whether or not we agree philosophically with the concept of a “national language,” English is clearly the dominant language in the United States. As such, knowledge of English is an important component to success in this country. The percent of people in the U.S. from non-English speaking nations is growing, which has fostered the search among grade schools, universities, and adult education programs, for the best methods to teach English to non-native speakers.
Research with songbirds and sophisticated brain imaging technologies provide some intriguing insights into how to best accomplish the goals of teaching (and learning) a second language.
“In humans as in songbirds, the sounds produced by the individuals themselves are essential for normal vocal development.”
Whistling Finches and Listening Children
Studies of song development in certain species of songbirds suggest that auditory feedback may be a crucial step in learning language.
Allison Doupe, a professor at the University of California, San Francisco, and postdoctoral fellow Michael Brainard study the way zebra finches develop their characteristic songs. Young male zebra finches learn a single tune early in life from their fathers. Doupe and Brainard have found that this learning process depends on the young finch being able to hear not only its father’s songs, but also its own attempts to vocalize the tune.
This requirement of auditory feedback in songbirds corroborates what has been seen in humans. Researchers came to understand this when, in the early 1970’s, they learned of a child named Genie who had been confined and raised without human contact or stimulation from the age of 20 months to 13 years. As a result, she displayed very abnormal vocalizations, particularly with syntax. Genie was almost completely unable to master things like verb tense, word order, prepositions or pronouns.
It is also known that older children who lose their hearing gradually lose their ability to form words properly. As Doupe and Brainard write in the October 2000 issue of the journal Nature Neuroscience: “These findings provide evidence that, in humans as in songbirds, the sounds produced by the individuals themselves are essential for normal vocal development.”
If auditory feedback is so important in the initial development of language, it stands to reason that it may also be required to learn a second language. Indeed, studies have shown that successful second language learners tend to enhance their communication skills by listening to the radio in the second language or by talking with native speakers. Thus, it appears that the combination of auditory input from the second language and the student’s own work to vocalize that language is key to learning.
Old Dogs Hear New Tricks
Anyone who has tried knows that as we enter adulthood, it is increasingly difficult to learn a second language. A study conducted by researchers at the Center for the Neural Basis of Cognition in Pittsburgh has shown that targeted auditory input can successfully help adults learn a second language.
Native Japanese speakers normally cannot distinguish between the English “r” and “l” sounds. Sound units of words are called “phonemes,” and studies suggest that as the language centers of our brain mature, certain phonemes are “wired” into those brain centers. , Phonemes that are not essential to the native language are not incorporated, implying that adult brains are simply less receptive to foreign phonemes.
Since the Japanese language does not distinguish between r and l, a single phoneme represents both sounds. When presented with English words containing either of these sounds, brain imaging studies show that only a single region of a Japanese speaker’s brain is activated, whereas native English speakers show different areas of activation for each sound. Learning to distinguish the phonemes might then actually require a “rewiring” of certain elements of the brain’s circuitry.
Jay McClelland, a co-director of the Pittsburgh study, has shown that some kind of plasticity remains even in adult brains. At the annual meeting of the Cognitive Neuroscience Society in 1999, he reported that adult Japanese speakers could learn to hear the difference in “r” and “l” if they were trained with the help of a computer that exaggerated each phoneme’s particular frequency or format. When the phonemes were modified and extended by the computer, the study volunteers were able to hear the difference between the sounds. With an hour’s worth of training, the volunteers could eventually hear the difference between the sounds, even when the phonemes were presented at the speed of normal speech.
The results from the Pittsburgh study suggest that although it may be more difficult to learn a second language as an adult, the same tools we used to initially learn our native languages also help us in acquiring a second language. This research shows that adult English language learners may be more successful if auditory sessions in which phonemes that seem particularly difficult for non-English speakers are extended and exaggerated until they are able to learn them at a normal speed.
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.