Context of the project:
My current work focuses on the synergies between lexical and syntactic acquisition. Several studies have shown that children can learn the meaning of new words (word semantics) by relying on the other words in the sentence (the syntactic context), a mechanism called syntactic bootstrapping (e.g. Gleitman, 1990). For instance, when hearing “It’s a pratch!” 18-month-olds can infer that pratch refers to an object, while upon hearing “It’s pratching!,” they can infer that it refers to an action. The question of how infants learn which syntactic contexts correspond to which semantic features is still unresolved (e.g. verb = action). Surely, infants’ ability to track statistical regularities must play some role. After all, syntactic categories are essentially distributional categories that are formed based on the occurrence of a set of words in the same context. Previous attempts to model distributional learning of categories have proven this to be feasible (e.g. Mintz, 2003). Preverbal infants possess another powerful tool for the initiation of syntactic categories: they have under their belt a handful of known words. Early understanding of the meaning of frequent concrete words starts around 6 months of age (e.g. “mommy”, “hand”), while the formation of semantic classes is thought to happen before the age of one (e.g. “ball” as object vs “eat” as action). Based on the semantic seed hypothesis (Christophe, Dautriche, Carvalho, & Brusini, 2016), infants could exploit this handful of known words as a seed for creating syntactic categories: they would track the syntactic contexts in which known words occur (e.g. objects such as ‘ball’ and ‘car’ appear after “This is a”), then infer that a novel word appearing in the same context is likely to share some semantic properties with the seed (e.g. “This is a” + “dax” -> dax = object).
The SASC project investigates the impact of a small developing lexicon on syntactic acquisition, as well as the strengths and the limits of the learning mechanism behind it. At this moment, there is a gap in the experimental literature, where theoretical frameworks based on computational models need to be tested in order to integrate new insights and to gain a complete picture of the mechanism that enables the acquisition of word meaning and the creation of syntactic categories. These insights will not only be used to interpret experimental data and to make new predictions for future studies, but also to understand morphosyntactic patterns in world’s languages. Inspection of cross-linguistic universals reveals that across the world’s languages, certain conceptual categories are often marked in morphosyntax (eg. object/action, animate/inanimate), while others are not. Hence, the SASC project also aims at giving us insight on the cause of the cross-linguistic regularity, which might be that since morphosyntax helps infants to learn word meanings, only those morphosyntactic regularities that mark conceptual distinctions that are noticeable by young infants would be selected for human languages. This project is building a bridge between researchers studying language acquisition, conceptual development, and language evolution.
Overall objectives:
Line 1 explores infants’ early sensitivity to the syntactic contexts of common words (nouns, verbs). Line 2 tests young children’s ability to use known and newly learned function words (i.e. pronouns, articles) to interpret the meaning of co-occurring novel words as either objects (nouns) or actions (verbs). Line 3 investigates young children’s ability to predict word semantics from new function words. This is done by introducing a new distinction that is found in natural languages, but absent from their own language (i.e. syntactic cues for animacy). Future ongoing work aims at testing the limits of this syntax-based inference to see whether languages’ morphosyntax is biased by «core cognition » distinctions.
