Coactivating the difference in the verbal domain of German Sign Language: A developmental perspective at signers processing signing and reading

• Applicants: Professorin Dr. Annika Herrmann; Professorin Dr. Barbara Hänel-Faulhaber
• Subject Area: Applied Linguistics, Computational Linguistics ; Individual Linguistics, Historical Linguistics
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 515745157

This project combines processing studies and the developmental perspective to tackle the question, whether or not plain and agreement verbs in German Sign Language (Deutsche Gebärdensprache: DGS) constitute distinct categories. In contrast to agreement verbs, plain verbs are lexically specified for their internal morpho-phonological structure and cannot be spatially modified. The question arises whether this verb type distinction is reflected in the neural time‐course of first language (L1) morphosyntactic processing during sign language comprehension in deaf adults. To this end, we will use verb agreement violations and restrictions on gapping structures while recording the electroencephalography (EEG). The project will also shed light on how morphosyntactic processing develops in deaf school‐aged children and hearing second language (L2) learners, and thus will assess co-activation effects in bimodal-bilinguals (BiBis) with various language backgrounds. By testing deaf children, we aim to clarify the generalizability of previous findings from studies of spoken language and assess whether the developmental trends observed in hearing children persist in deaf children. In addition, deaf children often experience delayed acquisition of their first language. Therefore, the project examines whether impoverished language input during the first years of life affects the time-course of morphosyntactic processing. As shown in previous research on bilinguals, co-activation processes from the L1 affect language processing in the L2. Thus, the project investigates to what extent morphosyntactic processing of the L1 (DGS) influences processing of the L2 (German) in deaf bimodal-bilingual adults and children and examines whether morphosyntactic co-activation is modulated by age of acquisition and/or language proficiency. Moreover, the development of hearing L2 learners’ sensitivity to DGS verb agreement across different learning stages will be assessed to contrast learning mechanisms of late sign language learning to (native) language acquisition in children. To our knowledge, bimodal-bilingual syntactic co-activation of a spoken and a signed language in general and subject-verb agreement in particular has not been investigated so far. The differences in subject-verb agreement between spoken and signed languages and the unique characteristics of subject-verb agreement in sign languages make this an ideal subject for investigating universal mechanisms of morphosyntactic co-activation. In the long-term view, this proposed research on signed and written language processing in deaf adults and children could provide important impulses to the linguistic diversity debate about appropriate language access for deaf children as well as fundamental insights for the discussion and the pedagogical design of contrastive language teaching in DGS and German.

• DFG Programme: Research Grants