My question is, Did Eric Lenneberg specify the "first language," excluding subsequent languages?
http://www.antimoon.com/other/myths-child.htm
"This is a more general version of the "foreign accent" myth described in the previous article in the series. It has its roots in the Critical Period Hypothesis proposed by Eric Lenneberg in 1967.
Lenneberg suggested that one's first language must be acquired before puberty (about 12 years of age). After puberty, he claimed, neurological changes in the brain make it impossible to fully learn a language. To support his hypothesis, Lenneberg pointed to examples of children who were kept in isolation from others and had no contact with their first language until after puberty. Such children kept making basic grammar mistakes, no matter how long they tried to learn the language.
The Critical Period Hypothesis has been generalized to refer to second/foreign language acquisition, leading to statements such as: "If you don't acquire a second/foreign language before puberty, you will always have problems with some parts of grammar" This causes language learners to interpret their flaws as a neurological necessity and discourages them from trying to improve. "
http://www.antimoon.com/other/myths-child.htm
"This is a more general version of the "foreign accent" myth described in the previous article in the series. It has its roots in the Critical Period Hypothesis proposed by Eric Lenneberg in 1967.
Lenneberg suggested that one's first language must be acquired before puberty (about 12 years of age). After puberty, he claimed, neurological changes in the brain make it impossible to fully learn a language. To support his hypothesis, Lenneberg pointed to examples of children who were kept in isolation from others and had no contact with their first language until after puberty. Such children kept making basic grammar mistakes, no matter how long they tried to learn the language.
The Critical Period Hypothesis has been generalized to refer to second/foreign language acquisition, leading to statements such as: "If you don't acquire a second/foreign language before puberty, you will always have problems with some parts of grammar" This causes language learners to interpret their flaws as a neurological necessity and discourages them from trying to improve. "