Code-switching across brainstorming sessions: implications for the revised hierarchical model of bilingual language processing.

The revised hierarchical model (RHM) of bilingual language processing posits independent word form representations for the dominant language (L1) and the nondominant language (L2), facilitated translation from L2 words to L1 words, access to common concepts for L1 and L2, and stronger activation of concepts for L1 than for L2. Spanish-English and English-Spanish bilinguals brainstormed for two sessions; half switched languages (L1-L2 or L2-L1) and half stayed in the same language (L1-L1 or L2-L2) across sessions. In both sessions, L1 brainstorming resulted in more efficient idea productivity than L2 brainstorming, supporting stronger concept activation for L1, consistent with the RHM. Switching languages from L2 to L1 resulted in the most efficient idea productivity in Session 2, suggesting that switching to L1 not only permits strong concept activation, but also the activation of concepts that are relatively different than those activated by L2, inconsistent with the RHM. Switching languages increased the proportion of Session 1 ideas repeated during Session 2, despite instructions not to repeat. This finding suggests that there is activation of concepts as well as word forms in same language brainstorming and that this dual activation aids in following instructions not to repeat, consistent with the RHM. It is suggested that the RHM be re-specified to accommodate the notion that L1 and L2 access relatively different concepts.