Researchers have argued that grouping heterogeneous linguistic profiles under a dichotomous condition might mask the cognitive effects of bilingualism. The current study used two different analysis approaches (i.e., continuous versus dichotomous) to examine inhibitory control in a sample of 239 young adult bilinguals. Dividing the sample into dichotomous groups based on L2 proficiency (i.e., high-proficient versus low-proficient) and L2 AoA (i.e., early versus late) did not lead to reliable group differences in any of the measurements used. However, the use of a continuous measure revealed that higher L2 proficiency predicted better visual inhibition and earlier L2 AoA was associated with better auditory inhibition. Furthermore, the observed differences were limited to tasks involving stimulus–stimulus competition, but not stimulus–response competition. These findings shed new light on the importance of conceptualising bilingualism as a continuous measure rather than a dichotomous measure and previous research on bilingual performance in different cognitive tasks.

This study examined the influence of letter transpositions on morphological facilitation in L1 English and L1 Chinese-L2 English speakers. Morphological priming effects were investigated by comparing morphologically complex primes that either contained transposed-letters (TL) within the stem or across the morpheme boundary, relative to a substituted-letter (SL) control. Within two masked primed lexical decision experiments, the same stem targets were preceded by morphologically related, TL-within, SL-within, TL-across, SL-across, or unrelated primes. Reaction time analyses with morphologically intact primes revealed facilitation in both L1 and L2 English. In L1, TL-within priming was significant, while the magnitude of TL-across priming varied as a function of positional specific bigram frequency and spelling proficiency. In L2, TL-priming was entirely absent. These findings support models of complex word recognition that accommodate relative flexibility in letter position encoding.