Language deprivation

Abstract: Children acquire language without instruction as long as they are regularly and meaningfully engaged with an accessible human language. Today, 80% of children born deaf in the developed world are implanted with cochlear devices that allow some of them access to sound in their early years, which helps them to develop speech. However, because of brain plasticity changes during early childhood, children who have not acquired a first language in the early years might never be completely fluent in any language. If they miss this critical period for exposure to a natural language, their subsequent development of the cognitive activities that rely on a solid first language might be underdeveloped, such as literacy, memory organization, and number manipulation. An alternative to speech-exclusive approaches to language acquisition exists in the use of sign languages such as American Sign Language (ASL), where acquiring a sign language is subject to the same time constraints of spoken language development. Unfortunately, so far, these alternatives are caught up in an "either - or" dilemma, leading to a highly polarized conflict about which system families should choose for their children, with little tolerance for alternatives by either side of the debate and widespread misinformation about the evidence and implications for or against either approach. The success rate with cochlear implants is highly variable. This issue is still debated, and as far as we know, there are no reliable predictors for success with implants. Yet families are often advised not to expose their child to sign language. Here absolute positions based on ideology create pressures for parents that might jeopardize the real developmental needs of deaf children. What we do know is that cochlear implants do not offer accessible language to many deaf children. By the time it is clear that the deaf child is not acquiring spoken language with cochlear devices, it might already be past the critical period, and the child runs the risk of becoming linguistically deprived. Linguistic deprivation constitutes multiple personal harms as well as harms to society (in terms of costs to our medical systems and in loss of potential productive societal participation).

Abstract: Bilingualism is common throughout the world, and bilingual children regularly develop into fluently bilingual adults. In contrast, children with cochlear implants (CIs) are frequently encouraged to focus on a spoken language to the exclusion of sign language. Here, we investigate the spoken English language skills of 5 children with CIs who also have deaf signing parents, and so receive exposure to a full natural sign language (American Sign Language, ASL) from birth, in addition to spoken English after implantation. We compare their language skills with hearing ASL/English bilingual children of deaf parents. Our results show comparable English scores for the CI and hearing groups on a variety of standardized language measures, exceeding previously reported scores for children with CIs with the same age of implantation and years of CI use. We conclude that natural sign language input does no harm and may mitigate negative effects of early auditory deprivation for spoken language development.

Abstract: A long-standing belief is that sign language interferes with spoken language development in deaf children, despite a chronic lack of evidence supporting this belief. This deserves discussion as poor life outcomes continue to be seen in the deaf population. This commentary synthesizes research outcomes with signing and non-signing children and highlights fully accessible language as a protective factor for healthy development. Brain changes associated with language deprivation may be misrepresented as sign language interfering with spoken language outcomes of cochlear implants. This may lead to professionals and organizations advocating for preventing sign language exposure before implantation and spreading misinformation. The existence of one—time-sensitive—language acquisition window means a strong possibility of permanent brain changes when spoken language is not fully accessible to the deaf child and sign language exposure is delayed, as is often standard practice. There is no empirical evidence for the harm of sign language exposure but there is some evidence for its benefits, and there is growing evidence that lack of language access has negative implications. This includes cognitive delays, mental health difficulties, lower quality of life, higher trauma, and limited health literacy. Claims of cochlear implant- and spoken language-only approaches being more effective than sign language-inclusive approaches are not empirically supported. Cochlear implants are an unreliable standalone first-language intervention for deaf children. Priorities of deaf child development should focus on healthy growth of all developmental domains through a fully-accessible first language foundation such as sign language, rather than auditory deprivation and speech skills.