Lay Publications

The influence of bilingualism on speech production: A systematic review

The influence of bilingualism on speech production: A Systematic Review
There is an increase in the number of children who speak more than one language (bilingual) entering the school system in English-speaking countries. This has implications for speech and language therapists as we know that children who are bilingual, and have a speech sound disorder, are less likely to be referred to speech and language therapy.  It can be difficult for speech and language therapists to know whether a child has a speech sound disorder or whether they are slow to learn English because they speak other languages at home.
The review identified all the previous studies that have investigated the development of language in English speaking bilingual infants and children. The article comments on how exposure to more than one language can impact a child’s ability to speak English. It also investigates research in to how these bilingual children with a speech sound disorder are identified and treated.
Findings from the review reported no clear evidence for ‘typically developing’ bilingual children learning speech at a slower or faster rate than their peers, but it is clear that bilingual children learn speech differently from their peers who speak a single language.  Bilingual children can produce atypical sounds in one or both languages, they show delayed acquisition of some sounds and accelerated acquisition of others, depending on interactions between languages spoken, and there is greater variation in rates of speech acquisition compared to monolingual children.  Even though more research is needed for conclusive evidence into the subject, findings from the review emphasise the importance for speech and language therapists to take a careful case history and assess speech sound production in both languages of a bilingual child.