Modelling bottom-up and top-down linguistic knowledge across different contexts of bilingual development

点击翻译按钮获取中文摘要

Although there are far more people in the world capable of using more than one language than there are monolinguals, idealized monolingual speakers remain the main source of evidence for our understanding of language knowledge, use, processing and acquisition. This project assumes that the ability to acquire, maintain and use more than one language is a key component of the human language faculty. We move bilingualism into the centre of linguistic inquiry and propose that this is the only approach capable of fully understanding the architecture of the human language learning capacity. By assessing the roles of frequency of the input and age of acquisition in lexical and grammatical development across different populations of bilinguals, we try to come to an integrated understanding of how language learning is similar to and how it is different from the learning of any other abstract skill.Using the acquisition and maintenance of grammatical gender in bilingual children and adults as a lens into the lexicon and the grammar, we compare how input frequency and age of second-language (L2) acquisition affect item-specific and rule-based aspects of lexical and grammatical development. We study interactions of frequency and age effects on rule application in an in-depth examination of lexical gender assignment and syntactic agreement among (i) simultaneous bilinguals (ii) early (child) L2 learners (iii) late (adult) L2 learners as well as (iv) child immigrants (early attriters) and (v) adult immigrants (late attriters). We focus on German as the target language among speakers with French or English as the other language, collecting data from a total of 480 participants. In a range of production and comprehension experiments, we test for differences in how these groups of bilinguals rely on phonological rules versus item frequency in identifying the lexical gender of words and how they recruit grammatical rules versus non-grammatical cues in the construction of syntactic gender agreement. In line with current approaches, we hypothesize that early L1 and L2 learners demonstrate rule-sensitivity with additive effects of input frequency, while late L2 acquisition is characterised by rule-sensitivity and input effects in the lexicon, yet underreliance on grammatical information in syntactic agreement. The analyses use mixed-effects regression models as well as structural equation modelling to model the contributions and interactions of frequency, age and background variables in lexical and grammatical acquisition and attrition. This project will yield a better understanding of how the language development interacts with factors such as the frequency of exposure and age of acquisition at different stages throughout the human lifespan, and provides novel insights into the question of whether language is learned by means of domain-general or domain-specific skills.