Raising and Educating a Deaf Child

International experts answer your questions about the choices, controversies, and decisions faced by the parents and educators of deaf and hard-of-hearing children.

Question from Ruth M. Denver, Colorado

There are various theories about a “window of opportunity for language learning” for children with hearing loss. What proof do we have that this window exists? If it does exist, does a window for the deaf child using a spoken language methodology have the same parameters as a deaf child using a sign language methodology? Can significant language learning occur after the typical window of opportunity has closed (i.e. after 5 years of age)?

Question from Ruth M. Denver, Colorado. Posted June 29, 2009.
Response from Rachel Mayberry - UCSD

In the Philadelphia airport, an English-speaking passenger told me that she gave up hope of teaching her six year old Spanish because someone had told her it was too late after 24 months.  What exactly was too late?  Learning to pronounce Spanish sounds like a native? Learning any Spanish at all?  Language is a highly complex and multi-faceted system, and there are many languages in the world.  When researchers ask if there is a particular age by which language can be learned or not, they typically measure one aspect of one language and then make generalizations.  Although hearing children learn much language by age 5, they learn the bulk of their adult vocabulary at older ages in school and do not master some complex grammatical structures until after the age of five.

Linguistically, we can describe language as being made up of a vast vocabulary, syntactic and morphological rules, and a phonological, or sub-lexical unit, system.  Communicatively, we express language through multiple modes: face-to-face comprehension and self-expression, accompanying gesture, and reading and writing.  It is important to consider this complexity because there are several hypotheses as to what specific aspect of language may be sensitive age of learning.  For example, the ability to pronounce a foreign or second language without an accent appears to depend on the age of language learning, although there are exceptions.  However, the adult ability to use and comprehend a second language depends more on the linguistic overlap between of the first and the second languages and how many years of education are done in the second language than age of learning alone.

What about learning a first language?  From retrospective studies where we measure the language skills of adults in relation to their early linguistic experiences, we know that children need to learn language in early life, any language, regardless of whether it is signed or spoken.  Adults who learned little spoken language during early childhood and then learned sign language at older ages show long-lasting deficits in their ability to comprehend any language, which is linked to lower reading levels and associated with specific cognitive deficits.  Moreover, not learning language in early childhood affects how the brain processes language in adulthood.

There seems to be a gradual decline in the ability to learn language efficiently, rather than an abrupt cutoff, for spoken and signed languages. How much language can be learned after early childhood appears to depend upon how much language was successfully learned in early childhood, regardless of whether it was signed or spoken.  In other words, language learning is cumulative and reciprocal across the languages that a person knows.  The more language a child knows, the easier and quicker he or she can learn additional language and skills, and other languages as well.

Learning a language at an early age is important, but it needs to be functional.  A child with hearing loss may be able to pronounce many speech sounds beautifully but still be in linguistic jeopardy.  Likewise, a child may produce signs in rapid succession but be at risk for comprehension problems.  The question is whether the child understands what is said or signed to him or her at an age appropriate level.  Can the child make himself specifically understood?  All children learn language, signed or spoken, by having lots of daily conversations with other children and adults.  So a child may begin to learn spoken or signed language at an early age, but if the child is not making real progress, this means that the child is not receiving enough linguistic input for language learning.  Children who do not make progress learning a spoken language nearly always learn to sign later.  Although they can produce sign, they often have marked comprehension problems.  How severe these comprehension problems are depends upon how much or little language they acquired at a young age (Mayberry, in press). For more information, see Mayberry, R. I. (in press). Early language acquisition and adult language ability:  What sign language reveals about the critical period for language. In M. Marschark & P. Spencer (Eds.), Oxford handbook of deaf studies, language, and education (Vol. 2). New York: Oxford University Press. and  Mayberry, R. I., Lock, E., & Kazmi, H. (2002). Linguistic ability and early language exposure. Nature, 417, 38.