We investigated cross-modal influences between speech and sign in hearing bimodal bilinguals, proficient in a spoken and a sign language, and its consequences on visual attention during message preparation using eye-tracking. We focused on spatial expressions in which sign languages, unlike spoken languages, have a modality-driven preference to mention grounds (big objects) prior to figures (smaller objects). We compared hearing bimodal bilinguals’ spatial expressions and visual attention in Dutch and Dutch Sign Language (N = 18) to those of their hearing non-signing (N = 20) and deaf signing peers (N = 18). In speech, hearing bimodal bilinguals expressed more ground-first descriptions and fixated grounds more than hearing non-signers, showing influence from sign. In sign, they used as many ground-first descriptions as deaf signers and fixated grounds equally often, demonstrating no influence from speech. Cross-linguistic influence of word order preference and visual attention in hearing bimodal bilinguals appears to be one-directional modulated by modality-driven differences.

This special issue began as a conference on Bilingual and Multilingual Interaction at Bangor University in 2012. The papers collected here all have novel elements, either because of their innovative methods, their unusual data, or their unexpected findings. They present findings from studies of bilinguals speaking six different pairs of languages, and use a range of methods including experiments, naturalistic observation and auditory judgment data. Despite the differences in subject matter and methodological approaches, all the papers demonstrate that bilinguals draw on resources which are different from those of monolinguals. They show that the two languages spoken by bilinguals have clearly discernible effects on one another, and that these effects can potentially be enhancing. Future research will no doubt build on the studies presented here and extend our understanding of cross-language effects in bilingual production and comprehension.

Spoken language (unimodal) interpreters often prefer to interpret from their non-dominant language (L2) into their native language (L1). Anecdotally, signed language (bimodal) interpreters express the opposite bias, preferring to interpret from L1 (spoken language) into L2 (signed language). We conducted a large survey study (N = 1,359) of both unimodal and bimodal interpreters that confirmed these preferences. The L1 to L2 direction preference was stronger for novice than expert bimodal interpreters, while novice and expert unimodal interpreters did not differ from each other. The results indicated that the different direction preferences for bimodal and unimodal interpreters cannot be explained by language production–comprehension asymmetries or by work or training experiences. We suggest that modality and language-specific features of signed languages drive the directionality preferences of bimodal interpreters. Specifically, we propose that fingerspelling, transcoding (literal word-for-word translation), self-monitoring, and consumers’ linguistic variation influence the preference of bimodal interpreters for working into their L2.