During auditory word recognition, lexical representations that match the input as the word unfolds are activated and compete for selection. The strength of a lexical competitor during this process depends on many factors, such a frequency of occurrence. These lexical characteristics affect competition within individuals who speak primarily one language, monolinguals (e.g., Marslen-Wilson, 1987). Within those who speak two or more languages, bilinguals, the same variables induce even stronger consequences (e.g., Bradlow & Pisoni, 1999).

In both speaker types, successfully managing lexical competition requires inhibiting lexical competitors according to some theories (e.g., McClelland & Elman, 1986; Norris, 1994). In bilinguals, lexical inhibition may be related to domain-general inhibition (e.g., Blumenfeld & Marian, 2011). This link is posited to underlie the bilingual advantage, which predicts that bilinguals are more efficient at managing lexical competition due to additional native and nonnative lexical competitors. This account contrasts with the entrenchment hypothesis (Diependaele et al., 2013), which states that individuals with more entrenched lexicons (i.e., monolinguals) more efficiently manage lexical competition. Both theories anticipate that domain-general inhibitory control may be a resource to manage lexical competitors. The current study seeks to answer questions relating to how different speaker groups manage lexical competition and if other cognitive resources come into play.

Participants completed a visual-world task, which assessed the degree of competitor influence during target access when targets and competitors phonologically overlapped (e.g., butter-bubble) and the competitor was present. A phonological priming task investigated processing of a previously inhibited target in prime-target pairs with phonological overlap. Competitor strength was operationalized by frequency in both tasks, with higher-frequency cohort competitors predicted to be stronger lexical competitors. Participants also completed tasks measuring domain-general inhibitory control.

Lexical competition was more evident in the visual-world than in the phonological priming task, and bilinguals were generally more susceptible to frequency effects in their second language, as predicted by the entrenchment hypothesis. Higher second language proficiency, a proxy for degree of lexical entrenchment, led to less competitor influence in bilinguals. Monolinguals outperformed bilinguals in domain-general inhibitory control, which did not exhibit any impact on the lexical competition process.