White Paper on Heritage Languages

This paper presents an overview of the linguistic system characteristic of heritage speakers and discusses several competing factors that shape this system in adulthood.

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A main focus of linguistics is to discover how grammatical knowledge is manifested in the brain, and which components may be universal. Many linguists believe in the universality of grammar, arguing that children receive too little input to develop language’s full complexity without some inherent structuring in the brain. (This is sometimes called the “poverty of stimulus” problem.) Language acquisition becomes even more complex when one considers the various degrees of fluency that are achieved. How much language exposure is needed to become a “native” speaker? And what about the role of age? Second-language learners who acquired the language after puberty, regardless of their level, persist in making mistakes that even the youngest of native speakers do not.

In Benmamoun, Montrul, and Polinsky (2010), referred to as BMP below, the focus is on heritage speakers – speakers of a language who interrupted or otherwise incompletely acquired their first language (or one of their first languages, in the case of children exposed to multiple languages from birth). For these speakers, one of the languages eventually becomes the primary language and the other weakens; this finding is at odds with the linguistic assumption that first languages are stable in adult speakers. Usually, the majority language of the country/region becomes the primary language, and the minority (incompletely acquired) language becomes the secondary. Depending on the situation, the heritage speaker might not receive formal education in the heritage language, which then remains rooted in a specific context such as the home and/or immediate community. Despite the fact that heritage speakers are given the same early linguistic exposure as native speakers, the interruption of their acquisition limits their grammatical competence, and this problem worsens by attrition as time passes. This group lies between L1 and L2 learners, making them an extremely useful source of linguistic information about acquisition and native competence.

Heritage speakers in the United States are usually immigrants or children of immigrants.  They are a diverse group, and using them in linguistic analysis is complicated. For example, incorrect self-reporting of language level may occur because they lack metalinguistic awareness, which further complicates the use of grammaticality judgment tests. Typically, we must deploy multiple linguistic diagnostics -- cloze tests and new tests of speech rate and lexical proficiency -- to study these speakers.

Despite these challenges, the study of heritage language learners offers many benefits. It lends insight into the cues that lead people to categorize a speaker as native or non-native. It also reveals much about the process of acquisition generally. For example, studies show that mere exposure to a language during the critical period is not enough to acquire native competence; the quality and quantity of exposure matter as well. (Being bilingual from birth sometimes actually results in a lower ability in the heritage language than being monolingual with a second language added later.)

 BMP analyze in detail six ways in which heritage speakers diverge from native speakers: phonology, lexical knowledge, morphology, syntax, case marking, and code-switching.

  • Phonology is generally an area in which heritage speakers excel, but a “heritage accent” may develop due to incomplete acquisition and attrition. This area has been understudied thus far. The authors suggest several fruitful directions for research. 
  • Lexical knowledge among heritage speakers is often much weaker than among native speakers; research on which basic lexical categories are most difficult for heritage speakers may help clear up the controversy over whether a noun-verb distinction is a component of Universal Grammar. (Studies so far seem to support the distinction even in these incomplete grammars.)
  • orphology, particularly inflectional morphology, is an area in which heritage speakers often have the most trouble. Preliminary research suggests some generalizations: They appear to struggle more with nominal morphology than verbal morphology (although there are differences as well within verbal morphology); agreement, aspect, and mood are much weaker areas in heritage speakers than is tense.
  • Syntax is more likely to be completely acquired, but some areas are problematic. Notably, complex syntax such as recursion and higher CP projections tends to be worse in heritage speakers. In languages with pro-drop, heritage speakers often lose that feature, possibly due to the difficulty of establishing syntactic dependencies. This also leads to issues with binding that may be manifested in problems with anaphors. Heritage speakers may also have difficulties with word order, passive constructions, and comprehension of relative clauses. (Some of these may originate from a neglect of the relevant morphology.)
  • Case marking is a common problem for heritage speakers. Inherent case may be highly affected, revealing that semantics does not escape weakness. Additionally, fine-grained semantics contrasts (such as definiteness, quantification, and genericity) are difficult for some heritage speakers. (We must note that these generalizations could stem from the influence of English, such that heritage speakers in countries with a different dominant language may exhibit different patterns. Further research in other contexts is required.)
  • Code-switching among heritage speakers occurs when two languages (or language varieties) are present in the same discourse segment. Code-switching involves embedding one language within the syntax of another; because it requires knowledge of many syntactic properties, code switching can be used as a tool for gauging heritage speakers’ knowledge of their languages.

Although they acknowledge that the data is far from comprehensive, BMP highlight three factors that help shape heritage grammars: incomplete acquisition, attrition, and transfer from the dominant language.

Incomplete acquisition (due to insufficient language input during childhood) often produces adult heritage speakers who pattern like child learners with regards to certain language features. Attrition is a much more controversial factor in heritage languages, partly because it is unclear at what point acquisition stops, but also because there is so much variation in heritage language. (For example, are there degrees of attrition in which features are present to lesser degrees than in full language?) BMP suggest that attrition may be present when a heritage speaker demonstrates difficulty with a language property that should have been fully acquired by age 4-5 (e.g., relative clauses). Finally, BMP highlight language transfer, which occurs when there is interference between the first language and the primary language. This is well documented in second language research, but should also be considered in the analysis of heritage languages.

BMP discuss four ways in which heritage language research can benefit the linguistic community.

First, heritage speakers allow us to investigate the phenomena that researchers have traditionally studied in children’s language use, but with test subjects that are more sophisticated and manageable. We can also test more complex theoretical issues, such as the relationship between agreement and case. (For example, should we classify the ergative as an inherent or as a structural case? Preliminary research suggests that structural case is more vulnerable than subject-verb agreement and inherent case, but agreement and structural case do not pattern together and may be disassociated – heritage language research could provide insights into the encoding of temporality and ergativity patterns.)

Second, heritage language studies that compare the grammatical competence of heritage speakers and L2 learners may have significant benefits. Heritage speakers have a distinct advantage when it comes to phonological competence, but no clear advantage in morphosyntactic competence. L2 learners make fewer mistakes in written language than heritage speakers, and tend to perform better in tasks that require metalingistic knowledge of the language.

Besides its value to theoretical linguists, heritage language research can benefit the field of education. Notably, because many heritage speakers sign up for second language classes in their heritage language, educators need to understand how to serve this large group of students. When special heritage tracks are created, they would benefit from materials that are “purpose-built” to address the strengths and weaknesses of heritage learners.

Finally, there are social benefits. On one hand, these accrue to the heritage language communities that wish to teach and maintain their languages and cultures. On the other, heritage speakers can be a resource of communication skills that benefit the nation in our increasingly globalized world.