From a neurophysiological point of view, learning a language is made possible by a highly developed central nervous system, by specialized brain mechanisms . 2 Animals have no such mechanisms. They can communicate in an elementary fashion via certain sounds and cries. They can, for example, communicate the idea of danger with cries of alarm, but they do not have the necessary mechanism in their cerebral cortex to speak. Nor is their brain sufficiently developed to master ideational speech.
Although young children's ability to learn language apparently decreases as they grow older, they are born with the potential "speech mechanisms" that make it possible for them to learn and to use language. Given the appropriate surroundings in which they hear a language, they will learn that language. The questions of concern are "How does the child acquire language?" and "What role do the brain mechanisms play in the language-learning process?"
The first step the child takes is to learn the concept. Penfield uses the example of a mother taking the child outside. As she does so she says, "Bye-bye." Gradually, the child acquires the idea of what bye-bye means. Once the child has the concept, it is stored in the memory as a "concept unit."
The next step is to learn the sound or sounds that signify the concept. Knowing the concept is not enough if speech is to be acquired. The child must learn the word that designates the learned concept. This "word-sound unit" is then stored at a different location in the brain. Next the child must establish an automatic reflex connection between the "word-sound unit" and its correlated "concept unit."
Up to this point in language learning the child has little advantage over the family dog. The dog, too, can learn the concept of going outside and the word that stands for that concept. Its reactions when someone mentions bye-bye
54 Part One: Theory
indicate that it knows a treat is in store. But beyond this point the dog cannot go. Only the children can take the next step. Only they have been born with a sufficiently elaborate and complex set of neuronal connections that allow them to speak. In order to communicate, children must activate a "verbal unit." This mechanism activates the muscles that are used to pronounce the words representing the concept.
When children begin to connect words in order to express themselves, an additional process becomes involved. They must select the words that they plan to use. Penfield stresses that the connection between thought and expression is not automatic. Humans make a conscious selection of the words and forms they need to communicate. This selectivity is made possible by the "centrencephalic system," which is "the system of central organizing connections that makes available to conscious thinking the many different neuronal mechanisms within the brain."
This, in a very simplified sense, is the pattern for learning a language. During the acquisition process, there is a time lapse of two to seven months from the time a concept is first heard until it is used meaningfully by the child. As children grow, they add "reading units" and "writing units." At first these units are selected consciously, but with practice they can become automatic. A person writing, for example, does not always have to pay conscious attention to his writing. The connections become so well established that thinking the thought is sufficient to have it appear on the written page.
Implications of the neurophysiological interpretation for second-language learning The preceding description of the neurophysiological processes developed in first-language learning contain the following implications for second-language learning:
1. Mental processes are basic to language learning. The teacher should concentrate on understanding and acquisition of concepts prior to practice.
2. Once the concepts have been learned, the students need practice in activating the "verbal units," the "writing units," and the "reading units" in order to increase their fluency in using the language.
3. Since school-aged children already have hundreds of concepts stored as "concept units," might it not be possible, and preferable, to help them learn vocabulary in the second language by associating new words with the known concepts? This approach would be a variation from the audio-lingual approach, which attempts to establish a "coordinate" set of concepts. It would also differ from the grammar-translation approach, which attempts to form associations between the "word-sound units" of the two languages, i.e., to teach vocabulary without taking advantage of known concepts or to connect words in the native language with words in the second language.
First-Language Learning