Language modality shapes the dynamics of word and sign recognition

Spoken words and signs both consist of structured sub-lexical units. While phonemes unfold in time in the case of the spoken signal, visual sub-lexical units such as location and handshape are produced simultaneously in signs. In the current study we investigate the role of sub-lexical units in lexical access in spoken Spanish and in Spanish Sign Language (LSE) in hearing early bimodal bilinguals and in hearing second language (L2) learners of LSE, both native speakers of Spanish, using the visual world paradigm. Experiment 1 investigated phonological competition in spoken Spanish from words sharing onset or rhyme. Experiment 2 investigated competition in LSE from signs sharing handshape or location. For Spanish, the results confirm previous findings for word recognition: onset competition comes first and is more salient than rhyme competition. For sign recognition, native bimodal bilinguals (native speakers of spoken and signed languages) showed earlier competition from location than handshape, and overall stronger competition from handshape compared to location. Hearing bimodal bilinguals who learned LSE as a second language also experienced competition from both signed parameters. However, they showed later effects for location competitors and weaker effects for handshape competitors than native signers. Our results demonstrate that the temporal dynamics of spoken words and signs impact the time course of lexical co-activation. Furthermore, age of acquisition of the signed language modulates sub-lexical processing of signs, and may reflect enhanced abilities of native signers to use early phonological cues in transition movements to constrain sign recognition.