Characterizing language production across modalities.

ABSTRACTThis study investigates factors influencing lexical access in language production across modalities (signed and oral). Data from deaf and hearing signers were reanalyzed (Baus and Costa, 2015, On the temporal dynamics of sign production: An ERP study in Catalan Sign Language (LSC). Brain Research, 1609(1), 40-53. https://doi.org/10.1016/j.brainres.2015.03.013; Gimeno-Martínez and Baus, 2022, Iconicity in sign language production: Task matters. Neuropsychologia, 167, 108166. https://doi.org/10.1016/j.neuropsychologia.2022.108166) testing the influence of psycholinguistic variables and ERP mean amplitudes on signing and naming latencies. Deaf signers' signing latencies were influenced by sign iconicity in the picture signing task, and by spoken psycholinguistic variables in the word-to-sign translation task. Additionally, ERP amplitudes before response influenced signing but not translation latencies. Hearing signers' latencies, both signing and naming, were influenced by sign iconicity and word frequency, with early ERP amplitudes predicting only naming latencies. These findings highlight general and modality-specific determinants of lexical access in language production.

Iconicity in sign language production: Task matters.

The present study explored the influence of iconicity on sign lexical retrieval and whether it is modulated by the task at hand. Lexical frequency was also manipulated to have an index of lexical processing during sign production. Behavioural and electrophysiological measures (ERPs) were collected from 22 Deaf bimodal bilinguals while performing a picture naming task in Catalan Sign Language (Llengua de Signes Catalana, LSC) and a word-to-sign translation task (Spanish written-words to LSC). Iconicity effects were observed in the picture naming task, but not in the word-to-sign translation task, both behaviourally and at the ERP level. In contrast, frequency effects were observed in the two tasks, with ERP effects appearing earlier in the word-to-sign translation than in the picture naming task. These results support the idea that iconicity in sign language is not pervasive but modulated by task demands. As discussed, iconicity effects in sign language would be emphasised when naming pictures because sign lexical representations in this task are retrieved via semantic-to-phonological links. Conversely, attenuated iconicity effects when translating words might result from sign lexical representations being directly accessed from the lexical representations of the word.

Influence of Gesture and Linguistic Experience on Sign Perception.

In the past years, there has been a significant increase in the number of people learning sign languages. For hearing second language (L2) signers, acquiring a sign language involves acquiring a new language in a different modality. Exploring how L2 sign perception is accomplished and how newly learned categories are created is the aim of the present study. In particular, we investigated handshape perception by means of two tasks, identification and discrimination. In two experiments, we compared groups of hearing L2 signers and groups with different knowledge of sign language. Experiment 1 explored three groups of children-hearing L2 signers, deaf signers, and hearing nonsigners. All groups obtained similar results in both identification and discrimination tasks regardless of sign language experience. In Experiment 2, two groups of adults-Catalan sign language learners (LSC) and nonsigners-perceived handshapes that could be permissible (either as a sign or as a gesture) or not. Both groups obtained similar results in both tasks and performed significantly different perceiving handshapes depending on their permissibility. The results obtained here suggest that sign language experience is not a determinant factor in handshape perception and support other hypotheses considering gesture experience.