Recent findings on the mechanisms of lexical access suggest that bilinguals are sensitive to the orthographic structure of their languages. Several studies have demonstrated that if presented with language-specific sub-lexical information, bilingual adults use this information to speed up word recognition, which provides evidence for language-selective lexical access. In the present study, we investigated the presence of such an early language detection mechanism in children.

Forty-six balanced bilingual third-graders performed two seemingly monolingual lexical decision tasks, one in English and one in German, including nonwords with different degrees of word-likeness in each language.

Accuracy scores and reaction times were analyzed for nonwords using mixed-effects models with the statistical software R.

Results show no impact of language-specific sub-lexical information on children’s performance in either task. We argue that bilingual lexical access is initially language-nonselective, and that sensitivity to language-specific orthographic structures first emerges over time. In contrast to bilingual adults, language detection in bilingual children is exclusively based on lexical information.

The present study provides first data on the detection mechanism for language membership at the early stages of bilingual reading development. We are the first to demonstrate an important difference in the architecture of the bilingual lexicon between children and adults.

Findings contribute to knowledge on the development of lexical access in bilinguals and pose limitations to the generalizability of the Bilingual Interactive Activation Plus (BIA+) extended model.