I’ve been meaning to post on a new(ish) paper we recently published in JSLHR on semantic deficits in bilingual children with language impairment. I will write about that, but what’s been on my mind is the issue of understanding children’s performance relative to their language experiences. In making diagnostic decisions about bilingual children who may have language impairment, we need to filter or interpret language performance through what it is we know about their age and experiences. For monolinguals age alone is usually a good index for linguistic experience. We expect that at certain ages, children will have had similar linguistic experiences. Thus, we can make predictions about what kinds of words, relationships among words, and number of words children should know by certain ages. For bilinguals, it’s not nearly as straightforward.We wrote about some of what to consider in making diagnostic decisions in a school context in a recent issue of AccELLerate, published by the National Clearinghouse for English Language Acquisition.
So, in addition to age, what do we need to know about?
Age of initial exposure to the L2. A number of researchers suggest that the age at which children first start learning a second language tells us something about what we should expect. Logically, the amount of experience children have with a language should help us judge whether or not their language performance is consistent with their level of cumulative exposure. It’s a complex relationship though because while it does take some time for children to learn a second language, children who have a good handle on their first language use this to quickly learn some aspects of their second language. In vocabulary, children seem to catch up relatively quickly. But this may not be true for all domains.
Current use and exposure to L1 and L2. In our research, we use a questionnaire developed for our test development project. We’ve gotten very good associations between exposure and use with children’s performance. We have also found that use is more tightly associated with grammatical performance but that exposure is more aligned with semantics.
In the new study on semantics in bilinguals with and without language impairment. We used both of these factors in addition to the usual suspects in matching our two groups of children. Basically, we matched on sex, age, year of first exposure to English, and percent input/output in Spanish and English. We felt that for bilinguals, we needed to go beyond just sex and age for matching so that we could better account for children’s linguistic experiences in Spanish and English as well as the length of time they had speaking each of their two languages. Matching each child with language impairment to one without LI, but who had similar language experiences in each of their languages helps us to understand the patterns associated with LI vs. those associated with second language learning or first language loss.