Greater inhibitory capacity relates to reduced within- and cross-language lexical competition during spoken word recognition: Evidence from eye movements using the visual world paradigm

Mercier, J. ^{1, 2} , Pivneva, I. ^{1, 2} & Titone, D. ^{1, 2}

1 Department of Psychology, McGill University, Montreal, Canada
2 Centre for Research on Language, Mind, & Brain, Montreal, Canada

Spoken language processing requires that individuals map a temporally unfolding and noisy acoustic signal onto stored knowledge about words in memory. In bilinguals, this task is presumably more challenging because words from both the target and non-target language are activated and must be suppressed. We investigated whether individual differences in inhibitory capacity affect spoken word processing in a second language (L2) context, and whether this relationship is modulated by L2 skills. We used the visual world paradigm, previously used to examine within- and cross-language lexical competition in bilinguals (Marian & Spivey, 2003), and a battery of inhibitory tasks.
Forty-eight French-dominant French-English bilinguals listened to English spoken target words (field) and looked at displays including the target, a word-onset within- (feet) or cross-language (fille) competitor, and unrelated pictures, while eye movements were monitored. We correlated composite scores of inhibitory function and estimates of within- and cross-language competition, time-locked to the target/competitor acoustic divergence point. In within-language competitor displays, greater inhibitory function correlated with increased fixations on the target (relative to the competitor) picture and decreased fixations on the competitor (relative to distracters). In cross-language competitor displays, greater inhibitory function correlated with increased fixations on the target (relative to the competitor) picture, and the correlation between greater inhibitory function and decreased fixations on the competitor (relative to distracters) was marginally significant. While increased L2 proficiency was associated with reduced within- and cross-competitor effects generally, the pattern of correlations with inhibitory capacity was not substantially different as a function of L2 proficiency.
These results suggest that individual differences in inhibitory function relate to both within- and cross-language competition during L2 spoken word processing. Moreover, while L2 proficiency is also associated with reduced within- and cross-language competition, it does not negate the relationship between inhibition and competition effects.