Linguists Case

The Age Effect

Several linguists, with Eric Lenneberg leading the way, have claimed that if a child is not exposed to language from early on, this child will never be able to fully ac-quire language, even if it should receive language input later (Lenneberg, 1967). The so-called critical age hypothesis is underpinned by cases in history, where children lived isolated for a longer time and were then not able to acquire language in the course of their lives. One of the most famous cases, where a child was not exposed to language during its childhood, is the case of Genie. She spent the first 13 years of her life in isolation, her parents neglected and abused her, and she never received any language input other than barking or grunting. After she was discovered in 1970 she was taken care of by therapists, teachers and linguists. But even after years of intensive training and support her "language contained many of the features of abnormal language development" (Lightbown & Spada, 2003, p. 20), such as slow production of speech, inefficient comprehension and false use of grammatical rules. It is understandable to assume, that Genie's incomplete language acquisition may be a result of her abusive and isolated upbringing, and of course the environment influences language acquisition. But there are other cases in which children grow up in a loving and caring family, and still do not receive the language input necessary to properly acquire language. This can happen when hearing parents have a deaf child. Since deafness of babies is often diagnosed rather late sign language input sets in later and so the child can end up having trouble learning the language (Lightbown & Spada, 2003, p. 20-21). Eric Lenneberg provides a neurological explanation for his thesis. He invokes a process occurring in the course of the development of the brain called lateralisation. Lateralisation describes the procedure when the two parts of the brain take over their specific tasks, meaning it leads to the specialisation of the two hemispheres (Edmondson, 1999, p. 126). Usually the left hemisphere holds the parts responsible for language. Neurologists assume that the lateralisation ends with puberty, probably between the ages of 9 and 13, before that "the brain's workings are apparently much more flexible and defuse" (Edmondson, 1999, p. 126), and thus providing best premises for language acquisition.

At first glance this conclusion seems coherent, and when regarding second lan-guage learning it appears even more logical. Who has not heard of the immigrant families, in which the children have next to native-like knowledge of the new lan-guage, whereas the older family members struggle with the simplest utterances? If it is not motivation or attitude, which keeps people from learning a language, age is easily made the scapegoat.

The most common explanation for these observations is that there is a 'critical period', during which the brain is flexible and language learning can occur naturally and easily. Since this period ends around puberty, adolescents and adults can no longer call longer call upon these natural learning capacities (Littlewood, 1987, p. 65).

In recent years, however, the belief in a "sharp cut- off point" (Myers-Scotton, 2005, p. 345), from which on language learning is near to impossible, has been criticised, and a lot research has been carried out to prove the questionability of the critical age hypothesis. Even so, it has to be pointed out, that the theory of a critical period is not wrong per se, only the strictness with which Eric Lenneberg approaches language learning is doubtful. Proposing that learning a language after the age of 13 is pointless because it will not lead to any success, only due to the structure of the brain, is a bit simple. Nevertheless it can be generally agreed on that in early childhood language learning seems effortless and appears to always result in fluency, whereas an adult learners' level of proficiency can stagnate. Also studies conducted by linguists, such as Robert DeKeyser