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Linguistic Resilience in CODAs:�Heritage Sign Language Acquisition & the Third Factor in Bimodal Bilingualism�

Stéphanie Papin, Assistant Professor at Universidad Rey Juan Carlos in the Deaf Community and Sign Language Degree.

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Introduction

CODAs: Children of Deaf Adults, often bilingual (spoken + sign)

Key Issue: How do CODAs acquire and blend two languages across different modalities?

Theoretical Anchor: Chomsky’s “Third Factor” in language acquisition

In this presentation, we explore how Children of Deaf Adults (CODAs), who grow up bilingual in sign and spoken languages, acquire language. We frame this within Chomsky’s "Third Factor"—general cognitive and biological principles that influence how language is acquired.

While Noam Chomsky's concept of the "third factor" in language design—referring to general principles and natural laws influencing language development—has been extensively discussed, direct applications of this concept to sign languages are limited in his own writings. Chomsky's seminal paper, "Three Factors in Language Design," outlines the interplay between genetic endowment, experience, and these general principles but does not specifically address sign languages.

However, the principles underlying the third factor have been influential in the study of sign languages. For instance, research by Edward S. Klima and Ursula Bellugi has demonstrated that sign languages possess complex grammatical structures akin to spoken languages, suggesting that universal cognitive principles shape language, irrespective of modality.

Additionally, the modality independence of language—the idea that linguistic capacity is not tied to a specific sensory modality—supports the notion that general cognitive principles (the third factor) play a significant role in language development. This is evident in how sign languages are fully capable of expressing the same range of complex ideas as spoken languages, adhering to universal grammatical principles.

This study exemplify how Chomsky's third factor can be applied to understand the structure and acquisition of sign languages: CODAs

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Chomsky’s Three Factors

Genetic Endowment – Universal Grammar
Linguistic Experience – Environmental Input
Third Factor – General cognitive and biological principles

We discuss Chomsky's three key components: genetic endowment (Universal Grammar), linguistic experience (input), and the Third Factor—broad cognitive principles that shape language learning across modalities, including sign languages.

In the case of sign languages, the Third Factor can be applied in several ways:

1. Neurological Constraints: Research shows that sign languages activate the same brain regions as spoken languages, suggesting that the human brain is naturally wired for linguistic structure, regardless of modality.

2. Efficiency in Language Design: Chomsky suggests that language is shaped by principles of computational efficiency. Sign languages, like spoken languages, exhibit structural economy, such as hierarchical organization and recursion, which are general cognitive principles.

3. Sensorimotor Adaptations: The modality of sign languages (visual-spatial) influences linguistic structure in ways that align with general cognitive and perceptual constraints, such as iconicity and gestural economy, rather than being dictated purely by genetic or environmental factors.

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Applying the Third Factor to Sign Language

Sign languages use visual-spatial modality but share structural features with spoken languages
Neurological and cognitive overlap with spoken language acquisition
Resilience of language even without formal input (homesigners)

Evidence from signers also calls into question the idea that language and other cognitive domains are completely distinct modules. This evidence comes from observations of negative cognitive effects associated with delayed linguistic access.

Connections between early language deprivation and cognitive consequences can be observed in several ways. For example, adult homesigners in Nicaragua do not perform in adult-like ways on tests of Theory of Mind (Pyers and Senghas 2009) or number cognition (Spaepen et al. 2011). Children who have experienced delayed language access may show negative consequences in Theory of Mind (Gale et al. 1996), Executive Function (M. L. Hall et al. 2018), numeracy (Contreras et al. 2018), and other cognitive domains

Goldin-Meadow herself has refrained from making the claim that the results of her research provide support for innate, language-specific knowledge of the type that Chomsky proposes, preferring to characterize the linguistic characteristics she observes as ‘resilient’ properties.

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Linguistic Resilience

Homesigners develop structured language despite minimal input
Key observations:

• Gesture-internal structure

• Sign order

• Recursion (Goldin-Meadow, 2003)

Linguistic resilience is evident in homesigners who develop language-like structures without full exposure. Their ability to produce sign order and recursive structures illustrates innate linguistic capabilities in action. Homesign systems (signs specific to the home), developed in families with deaf and hearing individuals, reveal innate grammatical structures, aligning with UG’s predictions regarding the spontaneous emergence of linguistic organization in the absence of structured input.

The 10 observations made by Goldin-Meadow and by others that homesigners produce structures that display characteristics including gesture-internal structure (Brentari et al. 2012), specific patterns of sign order (Goldin-Meadow and Mylander 1998), and recursion (Goldin-Meadow 1982), among many others, indicates that language learners develop not only based on external forces of input, but they also bring to bear powerful language-learning mechanisms that permit them to make use of complex structures found in all natural languages.

First is the observation of ‘resilience’, or the appearance of many language-like characteristics and properties in the absence of experience. Under a Chomskian view, these can be considered manifestations of the language acquisition device.

Second, without input from a community that shares a language, learners can only go so far on their own in developing their own language-like system.

A Chomskian interpretation of these findings would emphasize that core linguistic characteristics following from universal grammar require triggering, but not multiple generations of community interactions to slowly develop.

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Cognitive & Educational Implications

Early deprivation impacts:

• Theory of Mind

• Executive Function

• Numeracy

Bimodal bilingualism = cognitive advantage when nurtured

Acquisition is not instantaneous, and children (hearing or deaf) require input and a community sharing an accessible language. Children who cannot access spoken language and are not exposed to a natural sign language are surely in conditions of stimulus poverty. What is remarkable is that some properties of language nevertheless emerge, due to the intense drive to acquire a language. But despite the possibility for developing aspects of a language-like communicative system without accessible input, this kind of stimulus poverty leads to long-lasting negative effects on language and cognitive development. Importantly, whatever theories say about children’s linguistic resilience, language deprivation does hurt and must be avoided (W. Hall 2017; M. L. Hall, Hall, and Caselli 2019).

Early language deprivation can impair cognitive development, affecting Theory of Mind, numeracy, and executive function. Supporting early bilingualism in Deaf children can counteract these risks and enhance cognitive outcomes.

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95% of deaf people were born into non-signing hearing families.

90% of children of deaf parents are hearing.

What transmission of sign language?

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Deaf Parents:

Hearing children:

Oralised

No knowledge of SL

Do not consider themselves part of the deaf culture.

No acquisition

Have acquired SL at an adult age

They have varied SL competence and fluency.

Incomplete acquisition

No vertical transmission of SL

Horizontal process of inculturation in the deaf community

No exposure to SL

Partial exposure to SL

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Bimodal Bilingualism

Definition: Use of both a spoken and a signed language:

- Separate articulators (hands vs. mouth)

Code blending: Simultaneous sign and speech
Evidence of simultaneous processing and production

Bimodal bilinguals use both a sign and a spoken language, each involving separate articulators. Bilinguals use both languages to compose sentences (code switching), and in the case of bimodal bilinguals, the distinct articulatory modalities of their languages allow them to produce speech and signs simultaneously (code blending). Code blending is current between deaf parents and their hearing child. This dual modality allows for code-blending, providing evidence of simultaneous linguistic processing and neural integration.

Several different types of code-blending are discussed in connection to the predictions of the Synthesis model. Language Synthesis to capture bilingual phenomena including code-switching and 'transfer' as automatic consequences of the addition of a second language, using basic concepts of Minimalism and Distributed Morphology.

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Code-Blending in CODAs

SYSTEMATIC, NOT RANDOM

• FULL BIMODAL (SPEECH + SIGN)

• SPEECH-BASED OR SIGN-BASED

• COMPLEMENTARY (EACH LANGUAGE CONTRIBUTES DIFFERENTLY)

Code-blending among CODAs is systematic, not chaotic. It reflects an intuitive grasp of both languages' structures, supporting the view that bilinguals actively and fluently coordinate two grammars. Bimodal bilingualism provides further evidence for the cognitive flexibility of linguistic processing, as studies show that they engage in code-blending, simultaneously producing speech and signs, without conflict (Lillo-Martin et al., 2016). Thus, the main purpose of code blending is not to communicate separate pieces of information in two languages but to create a unified message by integrating content from both modalities.

It is important to note, however, that the physical ability to produce both languages simultaneously does not necessarily imply the capacity to consistently generate fully grammatical messages in both a signed and a spoken language (SpL) at the same time (Pizer, 2013).

Quadros notes in her participants’ code-blended output that one language can usually be identified as the primary language because it contributes most of the grammatical structure to the utterance, while the other language is relegated to secondary status. Primary and secondary languages generally align with the bilingual’s language dominance or preference, but bilinguals can also switch between primary languages from utterance to utterance, often for sociolinguistic motivations.

In language acquisition studies of hearing children with bilingual input it has been found that if the parent(s) mix their languages, children are influenced by this mixed input. The children in these deaf families are therefore exposed to a variable input, and, as research with hearing children has indicated, input determines the amount and type of code mixing that children produce (Nicoladis & Secco 2000).

In language contact situations it has been claimed that a third system can emerge as a language variant (Romaine 1995). She describes this third system as follows: In situations of intense language contact it is possible for a third language system to emerge which shows properties not found in either of the input language. Thus, through the merger or convergence of two systems, a new one can be created. (Romaine 1995:4)

Mallory, Zingle & Schein (1993) investigated from a socio-linguistic perspective the language use in several deaf families and found considerable variation and considerable mixing.

According to previous research, children prefer to use their dominant language and code-mixing more often when speaking their nondominant language and using words for which they do not have a translation equivalent (Genesee et al., 1995; Nicoladis & Secco, 2000). The concept of DOMINANT LANGUAGE usually refers to the language the child is more fluent in, producing longer utterances and more different word types (Genesee, Paradis & Crago, 2008, p. 80).

The GAP-FILLING HYPOTHESIS refers to the phenomenon where a child usually code-mixes to compensate for gaps, e.g., in lexicon or grammar in one language by inserting structures or words from another language (Genesee, Boivin & Nicoladis, 1996; Montanari, 2009; Nicoladis & Secco, 2000; Pearson, Fernández, Lewedeg & Oller, 1997).

However, Baker and Van den Bogaerde concluded (2008) that children can use code-mixing in their utterances only when they have enough proficiency and fluency in both of their languages. Children may sometimes use code-mixing also for PRAGMATIC REASONS. In these cases one of the languages has more affective weight than the other or the child is able to express something in one of the languages in a way that is not possible for him/her with the other language, e.g., when emphasising important things or narrating events (see, e.g., Lanvers, 2001).

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Language Synthesis Model

No special bilingual mechanism needed
One language often provides grammatical frame (matrix language)
Sentence structure may reflect elements from both languages

The Language Synthesis Model posits that bilinguals use one language for grammatical structure while inserting elements from another. This model assumes a universal computational system, not a specialized bilingual mechanism, the computational system is assumed to be universal. As González-Vilbazo and López put it, “what is distinctive of bilingual speakers is that they have functional and lexical items belonging to two different lexica.”

Bimodal bilinguals, fluent in a signed and a spoken language, exhibit a unique form of bilingualism because their two languages access distinct sensory-motor systems for comprehension and production. Differences between unimodal and bimodal bilinguals have implications for how the brain is organized to control, process, and represent two languages. Evidence from code-blending indicates that the production system can access two lexical representations without cost, and the comprehension system must be able to simultaneously integrate lexical information from two languages. Further, evidence of cross-language activation in bimodal bilinguals indicates the necessity of links between languages at the lexical or semantic level. Finally, the bimodal bilingual brain differs from the unimodal bilingual brain with respect to the degree and extent of neural overlap for the two languages, with less overlap for bimodal bilinguals.

Under these circumstances, inhibition of one language is cognitively more costly (effortful) that code blending. Emmorey, Borinstein et al. (2008) and Casey and Emmorey (2009) noted that the primary function of code blending is not to convey distinc information in two languages, but rather to construct a single message (proposition) from content in two modalities. The choice of a matrix language is likely made at relatively early stages in production because one language must provide the syntactic frame.

This shows that language synthesis occurs, even when a language is inactive, but language synthesis happens because languages are active, even when one of the languages is preferred or used more. There is a strong tendency to choose one language to drive the derivation, but both languages are in the syntactic computation game. Bilinguals use both languages to compose the sentence. In the case of bimodal bilinguals, as the languages present different articulators, they can be produced simultaneously.

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Implications for Heritage Sign Language Acquisition

• Language dominance shifts

• Parental input variations

• Code blending

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Results

Home Signs and Compensation

Cross-Modal Synthesis

Role of SL Education

Standardization Challenges

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Home Signs and Lexical Compensation

Use of improvised gestures in families

Developed due to limited SL exposure

Functioned as private codes

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Home Signs and Lexical Compensation

“There are concepts that we would make up a sign and then keep using it.”

“It was unstructured communication… I communicated in a very rudimentary way, inventing signs.”

“Communication was fluid… there was quite a lot of home signs of their own.”

“With my parents we use a private LS… our own oral and signs because they don't speak SL.”

“We had our own codes… but since everything was visuogestual, we understood each other perfectly.”

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Cross-Modal Synthesis and Identity

Code-blending common

Adaptation to interlocutors

Use of facial grammar, iconicity

Identity signaling through modality

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Cross-Modal Synthesis in spoken language

“I've been told that I talk with my hands a lot… it has this influence on me even when I am not actually signing…”

“What I see in others physically has a lot of influence… the vision I have of the bodily expression ”

“I realized that I really need to see my partner when he talks to me from the other room, I always get angry if I don't see you, I don't understand you. Everything goes through the eyes, of course.”

“The facial expression, I didn't know that it was so linked to SL. It just come naturally to me, I guess that after being all my life talking to deaf people and seeing that they made different gestures on their faces, I kind of absorbed that way of speaking”

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Impact of Formal SL Education

Revealed unconscious language patterns

Led to 'unlearning' informal syntax

Increased metalinguistic awareness

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Retaining and reactivating core grammatical structures

“Complex concepts that I had seen but not understood at all until taking SL classes: the role of facial expression and use of space. It made me aware that all of this already existed in my body,”

“There were many things I did not know in depth. For example, the origin of the signs, for me it was also an enrichment because I was not always aware of it.”

“In spite of doing bimodal, I had previous knowledge, the teachers told me that I had good expressions and resources. Not that I had a very high level, but a good base.”

“I was told that I made mistakes in the signs and bimodal but my understanding was organic.

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Challenges in Standardization

Conflict with teachers over 'correct' signs

Emotional reactions: pride vs. frustration

Tension between intuitive use and academic expectations

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Perceptions of CODA Varieties in the Classroom

“The teacher told me it was confusing… a lot of old signs and roles, mimics, a lot of body and very little vocabulary.”

“I lack technique compared to them, and they lack Deaf culture compared to me.”

“Others look at me perplexed if I use voice or mime… but these are things that Deaf people do.”

“It was difficult for me to know which was the formal register… the class contents were very linear.”

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Summary and Implications

CODAs show linguistic resilience

Bimodal input shapes dynamic repertoires

Need for tailored pedagogies

CODAs often experience uneven input or artificial sign systems, yet they demonstrate competence.

This highlights the resilience of language acquisition under constrained conditions.

They can retain core grammatical structures and can refine their linguistic skills, indicating the robustness of UG In preserving linguistic competence despite variable input conditions.

CODAs show that both spoken and signed languages follow shared cognitive principles. Their bilingualism is a creative, resilient, and cognitively rich form of language use, bridging Chomsky’s theoretical framework with real-world language development.

They still develop linguistic competence through synthesis and resilience.

The results call for educational practices that recognize the unique linguistic profiles of CODAs and support them through personalized and culturally sensitive instruction.

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Further investigation

Syntactic and grammatical structures and other common skills in heritage signers, including iconicity, and pragmatic resources of cohesion in discourse, such as roles and non-manual components.
Variations specific to language contact and resulting from linguistic deprivation, such as the use of homemade signs.

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References

Emmorey et al. (2008)
Goldin-Meadow (2003)
Chomsky (1969)
Pyers & Senghas (2009)
Lillo-Martin et al. (2016)

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stephanie.papin@urjc.es

@stefpapin

@gradoLSE_URJC