Signed languages – Unique and ordinary: A commentary on Kidd and Garcia (2022)

We fully endorse the main point of Kidd and Garcia’s (2022) article, and stress that much additional research on the acquisition of non-WEIRD (Western, Educated, Industrialized, Rich, Democratic) and other under-represented languages is sorely needed. The article helpfully illustrates the current status of research (as published in four ‘main’ language acquisition journals), provides supporting reasons for wanting to change the status quo, and suggests a few means for remediation. While the data presented in the article are very helpful, we stress that in many cases, acquisition research is published in outlets other than the four journals surveyed, and this might be especially true for research on languages other than English, or research conducted by residents of non-English-speaking countries. While Kidd and Garcia note this limitation of their study, we think it is important for research published in multiple outlets, including ones not written in English, to be included in the canon. So, we would call for researchers to gain more familiarity with research published in other journals, since some researchers may (for multiple reasons) prefer not to publish their work in major English-language journals. For those who do so wish, we join Kidd and Garcia’s call for a greater diversity of languages and researchers represented, which may require editors and reviewers to adopt a broader mindset about the work to be published in their journals.

Research on natural signed languages is an important component of the goal of broadening the database of knowledge about how languages are acquired. According to Kidd and Garcia’s analysis, 5 of the 103 languages represented in the journal publications are natural signed languages, which were discussed in 24 articles, or fewer than 1% of the total. We know of research on the acquisition of perhaps another half-dozen signed languages published in other outlets, but even so, it is clear that much more research is needed. It is important for researchers to know about the nature and acquisition of signed languages. Natural signed languages (such as American Sign Language [ASL], British Sign Language [BSL], and Turkish Sign Language [TİD], among the languages listed in Kidd and Garcia’s Table A1) have many of the same characteristics that spoken languages have (Jepsen et al., 2015; Pfau et al., 2012; Sandler & Lillo-Martin, 2006), and under the right circumstances are acquired in much the same way that spoken languages are acquired (Chen Pichler et al., 2018). ¹ When signed languages are excluded from theories of language, we fail to understand how resilient the faculty of language is, and how remarkable are the similarities of language acquisition in contexts with adequate sustained input, despite the obvious differences associated with the modality of language.

Nevertheless, the visual/gestural modality through which signed languages are conveyed does contribute to some differences. For example, signed languages tend to employ multi-morphemic mono-syllabic grammatical structures, made possible by the use of multiple large visible articulators that can condense different sources of information (Brentari, 1998). Also, the visual/gestural modality can more readily iconically convey visual characteristics of referents, and this iconicity plays a role in signed language acquisition (Caselli & Pyers, 2020).

While effects of the modality and other (possibly typological) differences in the structure and acquisition of signed languages as opposed to spoken languages provide strong motivation for including them in any theory or characterization of how language develops, we caution that emphasizing differences between signed and spoken languages can lead to unwanted consequences. The fact that signed languages and spoken languages have so many similarities despite the differences is striking. Signed languages serve the same functions as spoken languages and rely on largely the same cognitive resources, so major similarities can be expected. Signed language researchers over the past decades have emphasized the similarities between languages in different modalities in part because this framing has been needed for recognition of the status and appropriateness of signed languages in the lives of deaf communities (Jokinen, 2000). While the World Federation of the Deaf has issued a Charter proclaiming the rights of deaf children to access natural signed languages (World Federation of the Deaf, 2019), this access is unfortunately often still restricted. We are concerned that the focus on spoken languages in linguistic research, and the emphasis on differences between signed and spoken languages, may give the false impression to physicians, early intervention providers, teachers, and parents that signed languages are too different – too difficult for parents to learn, too easy for children to learn later, too awkward for use in public, too limited in expressive ability – and therefore an approach using spoken language only should be the first choice for parents of deaf and hard-of-hearing children (for discussion, see Humphries et al., 2017). If the similarities between signed and spoken languages were more widely known, such detrimental attitudes might be reduced.

This is not to say that everything one would want to know about signed languages and their acquisition is already known! Indeed, there are many, many open questions about the acquisition of signed languages, including ASL, BSL, and other more widely studied signed languages, not to mention under-represented signed languages. Research on signed language acquisition is often published in outlets other than the four journals used for this study, but even so, the call for study of a much wider range of languages applies to signed languages just as to spoken languages.

What steps can be taken to expand research on the acquisition of signed languages? Kidd and Garcia suggest that technology might help language acquisition researchers, and recommend this specifically for the production of signed language corpora. We have been engaged in developing a corpus of signed language acquisition data, the SLAAASH corpus (Lillo-Martin & Chen Pichler, 2008) as well as technical tools to support signed language annotation, such as the ASL Signbank (Hochgesang et al., 2021). Advances in technology have indeed been important over the decades since the original acquisition data were recorded on Beta and VHS (Video Home System) tape. As described in Hochgesang (2022), however, the process of making video data searchable and usable for acquisition research is extremely time-consuming and requires expert contributions from members of signing communities, as well as more resources than have been available. Furthermore, well-designed platforms for appropriately sharing curated materials are needed. As Kidd and Garcia suggest, it is crucial that work in this area be more solidly supported by grants, publications, recognitions of corpus-building activities, and other means (see also Berez-Kroeker et al., 2018). And, of course, such efforts are needed around the world, particularly in areas other than North America and Europe, which have seen the bulk of signed language research, and must be led by the local communities of signers with appropriate and lasting investment in stable infrastructure that are led and maintained by members of the signing communities themselves.

We also call for removing existing barriers to training and education for would-be researchers, especially those interested in working on signed languages. Frequently, educational gaps for deaf students in the formative years lead to significant obstacles in access to education which is offered exclusively in a community’s dominant spoken/written language. This preference for education in a language other than the signed languages which are more accessible often leads to such systemic inequalities. We applaud the approach taken in Brazil (Quadros & Stumpf, 2019), where Bachelor’s programs were developed to be conducted entirely in Libras (the natural sign language of Brazil), leading to degrees for hundreds of deaf students and higher degrees (MA and PhD) for many in just a few years.

More research on a broader number of signed languages is clearly needed. We advocate for the recognition of signed languages, for signed language research, and for the empowerment of community members to lead this research, as in the example of the Inclusion in Sign Language Linguistics project led by Dr. Lina Hou (https://sites.google.com/view/inclusion-sign-language/home). It is also important for researchers who do not work on signed languages to understand important findings about signed language acquisition, and to include natural signed languages in their teaching. Only with such efforts will signed languages, their acquisition, and research with them be recognized as truly special and also completely normal.