Post 130: Case Study for Critical Period Hypothesis

Post 130: Case Study for Critical Period Hypothesis

The critical period hypothesis is the subject of a long-standing debate in linguistics and language acquisition over the extent to which the ability to acquire language is biologically linked to age. The hypothesis claims that there is an ideal time window to acquire language in a linguistically rich environment, after which further language acquisition becomes much more difficult and effortful.  that language acquisition occurs primarily, possibly exclusively, during childhood as the brain loses plasticity after a certain age. It then becomes rigid and fixed, and loses the ability for adaptation and reorganisation, rendering language (re-)learning difficult. Penfield and Roberts (1959) claim children under nine can learn up to three languages: early exposure to different languages activates a reflex in the brain allowing them to switch between languages without confusion or translation into L1 (Penfield, 1964). Lenneberg (1967) asserts that if no language is learned by puberty, it cannot be learned in a normal, functional sense.

For the most part, I agree with the Critical Period Hypothesis popularized by Stephen Krashen that there is a critical period of time for the brain to learn languages and attain a perfect native like accent. After the brain lateralizes, that is develops the ability to put logical information into the left hemisphere and artistic/sentimental information into the right hemisphere, then the child loses the ability to attain a perfect accent since the person starts to analyze each new language he learns to his L1. This occurs around the age of 11 or at puberty as the brain matures and loses certain neurological functions for perfect speech.

When I was a toddler, I was exposed to only Chinese. Chinese has three tones that most Americans find hard to emulate at a later age. Each Chinese word will have a different meaning based on these 3 tones. If you use the wrong tone, you have a totally different meaning for the word. Ma in first tone means 'mother'. Ma in second tone means horse. Ma in third tone means angry. If you want to greet your mother in law, if you use the wrong tone, you may end up calling your mother in law a horse. Up to a certain age, a child can pick up these perfect tones for Chinese pronunciation without problem. But after puberty, then the language learner will have a hard time with the tonality of Chinese typical of American adult Chinese learners.  Since I was exposed to Chinese as a toddler, I speak Chinese with a native-like accent.

I also learned French when I was in 4th grade, so I am told that I speak French with a native-like Parisian accent, although I do make some mistakes with a very slight American accent especially if I am out of practice. Once I am in France for a few months, my native-like accent that I acquired in elementary school when I learned French comes right back.  I learned French before the puberty cut off when the brain starts to become rigid and fixed and starts to compare all new languages to L1.

However, I learned Spanish at the old age of 27. As a result, out of my three languages, my Spanish is the worst. I can understand what Spanish speakers say, but when I try to speak Spanish, I have a heavy American accent and I lack vocabulary as well in Spanish. However, through charades a native Spanish speaker can understand what I want. I can tell a Spanish speaker if I want something fixed in my apartment in Spanish, but very rudimentary Spanish since I learned this language very late. For me, the later I learned the language, the worse I speak it.

When my grandmother tried to learn English in her 60's and 70's, she never got beyond first grade English in her reading and writing. I remember when she used to write me Xmas cards in English, I thought her handwriting looked just like mine. (I was in first and second grade at the time). I remember thinking, "How can an adult write just like me a child?" especially after my 1st grade teacher had just scolded me on writing 'childishly' and that adults have much more elegant 'adult' handwriting because of years of practice. I thought Grandma did not practice her handwriting enough and that's why she had such 'childish' handwriting. Of course, the real reason why Grandma wrote that way was because she was trying to learn English at a very late age. Today, I admire Grandma for trying to learn English at such a late age and later I admire Grandma even more when she got her American citizenship at the age of 80.

The Critical Period Hypothesis postulates that the later you learn a L2, the harder it becomes and the thicker your accent becomes. It also becomes harder to read and write in the L2, not just speak in the L2 if you learn the L2 at a later age due to interlanguage fossilization.  It is too bad humans cannot retain that childlike ability to learn languages all their lives!