Is there a relation between onset age of bilingualism and enhancement of cognitive control

TLDR: Early bilinguals and monolinguals demonstrated similar levels of English proficiency, and both groups were more proficient in English than late bilinguals as discussed by the authors, suggesting a gradient in which more experience in being actively bilingual is associated with greater advantages in cognitive control and higher language proficiency.

Abstract: Young English-speaking monolingual and bilingual adults were examined for English proficiency, language use history, and performance on a flanker task. The bilinguals, who were about twenty years old, were divided into two groups (early bilinguals and late bilinguals) according to whether they became actively bilingual before or after the age of ten years. Early bilinguals and monolinguals demonstrated similar levels of English proficiency, and both groups were more proficient in English than late bilinguals. In contrast, early bilinguals produced the smallest response time cost for incongruent trials (flanker effect) with no difference between monolinguals and late bilinguals. Moreover, across the whole sample of bilinguals, onset age of active bilingualism was negatively correlated with English proficiency and positively correlated with the flanker effect. These results suggest a gradient in which more experience in being actively bilingual is associated with greater advantages in cognitive control and higher language proficiency.

Figures

Figure 1. Sample stimuli in the flanker task.

Table 3. Mean response times and standard deviations for correct trials in the three conditions of the flanker task.

Figure 3. Overlayed scatterplots of correlations between onset age of active bilingualism and PPVT–III standard scores and flanker effect.

Figure 2. Mean RT costs for congruent and incongruent trials in conflict block relative to control trials and the flanker effect (Incongruent–Congruent) by language group.

Table 1. Summary of studies reporting a bilingual advantage in cognitive tasks indicating age of participants, age of onset of bilingualism (L2A), and length of bilingual experience.

Table 2. Means and standard deviations for background measures by group.