Discourse fluency modulates spoken word recognition in monolingual and L2 speakers

We investigated whether fluent language production is associated with greater skill in resolving lexical competition during spoken word recognition and ignoring irrelevant information in non-linguistic tasks. Native English monolinguals and native English L2 learners, who varied on measures of discourse/verbal fluency and cognitive control, identified spoken English words from dense (e.g., BAG) and sparse (e.g., BALL) phonological neighborhoods in moderate noise. Participants were slower in recognizing spoken words from denser neighborhoods. The inhibitory effect of phonological neighborhood density was smaller for English monolinguals and L2 learners with higher speech production fluency, but was unrelated to cognitive control as indexed by performance on the Simon task. Converging evidence from within-language effects in monolinguals and cross-language effects in L2 learners suggests that fluent language production involves a competitive selection process that may not engage all domain-general control mechanisms. Results suggest that language experience may capture individual variation in lexical competition resolution.