A computational analysis of semantic structure in bilingual verbal fluency performance

Groups of English monolingual and English-French bilingual participants completed letter and category fluency tasks, either only in English (monolinguals) or in English, French, free-switch and forced-switch conditions (bilinguals). Response patterns were modeled using a semantic space approach that estimates the weight of frequency and semantic similarity information in determining output patterns. Overall, semantic similarity had a stronger influence on output patterns than did frequency. In the forced English-French switching condition, the weight of similarity information was reduced and the weight of frequency information was increased, suggesting that the increased executive demands related to language switching result in alterations in the semantic structure of fluency output. Moreover, the frequency and similarity model parameters were negatively correlated in all tasks, indicating that they may be in competition during verbal fluency tasks.