Publications

Abstract

Emergentist approaches to language acquisition identify a core role for language-specific experience and give primacy to other factors like function and domain-general learning mechanisms in syntactic development. This directly contrasts with a nativist structurally oriented approach, which predicts that grammatical development is guided by Universal Grammar and that structural factors constrain acquisition. Cantonese relative clauses (RCs) offer a good opportunity to test these perspectives because its typologically rare properties decouple the roles of frequency and complexity in subject- and object-RCs in a way not possible in European languages. Specifically, Cantonese object RCs of the classifier type are frequently attested in children’s linguistic experience and are isomorphic to frequent and early-acquired simple SVO transitive clauses, but according to formal grammatical analyses Cantonese subject RCs are computationally less demanding to process. Thus, the two opposing theories make different predictions: the emergentist approach predicts a specific preference for object RCs of the classifier type, whereas the structurally oriented approach predicts a subject advantage. In the current study we revisited this issue. Eighty-seven monolingual Cantonese children aged between 3;2 and 3;11 (Mage: 3;6) participated in an elicited production task designed to elicit production of subject- and object- RCs. The children were very young and most of them produced only noun phrases when RCs were elicited. Those (nine children) who did produce RCs produced overwhelmingly more object RCs than subject RCs, even when animacy cues were controlled. The majority of object RCs produced were the frequent classifier-type RCs. The findings concur with our hypothesis from the emergentist perspectives that input frequency and formal and functional similarity to known structures guide acquisition.

Abstract

In this study we test the hypothesis that symbolic play represents a fertile context for language acquisition because its inherent ambiguity elicits communicative behaviours that positively influence development. Infant-caregiver dyads (N = 54) participated in two 20-minute play sessions six months apart (Time 1 = 18 months, Time 2 = 24 months). During each session the dyads played with two sets of toys that elicited either symbolic or functional play. The sessions were transcribed and coded for several features of dyadic interaction and speech; infants’ linguistic proficiency was measured via parental report. The two play contexts resulted in different communicative and linguistic behaviour. Notably, the symbolic play condition resulted in significantly greater conversational turn-taking than functional play, and also resulted in the greater use of questions and mimetics in infant-directed speech (IDS). In contrast, caregivers used more imperative clauses in functional play. Regression analyses showed that unique properties of symbolic play (i.e., turn-taking, yes-no questions, mimetics) positively predicted children’s language proficiency, whereas unique features of functional play (i.e., imperatives in IDS) negatively predicted proficiency. The results provide evidence in support of the hypothesis that symbolic play is a fertile context for language development, driven by the need to negotiate meaning.

Abstract

There is consensus that the adult lexicon exhibits lexical competition. In particular, substantial evidence demonstrates that words with more phonologically similar neighbors are recognized less efficiently than words with fewer neighbors. How and when these effects emerge in the child's lexicon is less clear. In the current paper, we build on previous research by testing whether phonological onset density slows lexical access in a large sample of 100 English-acquiring 30-month-olds. The children participated in a visual world looking-while-listening task, in which their attention was directed to one of two objects on a computer screen while their eye movements were recorded. We found moderate evidence of inhibitory effects of onset neighborhood density on lexical access and clear evidence for an interaction between onset neighborhood density and vocabulary, with larger effects of onset neighborhood density for children with larger vocabularies. Results suggest the lexicons of 30-month-olds exhibit lexical-level competition, with competition increasing with vocabulary size.

Abstract

How children learn grammar is one of the most fundamental questions in cognitive science. Two theoretical accounts, namely, the Early Abstraction and Usage-Based accounts, propose competing answers to this question. To compare the predictions of these accounts, we tested the comprehension of 92 24-month old children of transitive sentences with novel verbs (e.g., “The boy is gorping the girl!”) with the Intermodal Preferential Looking (IMPL) task. We found very little evidence that children looked to the target video at above-chance levels. Using mixed and mixture models, we tested the predictions the two accounts make about: (i) the structure of individual differences in the IMPL task and (ii) the relationship between vocabulary knowledge, lexical processing, and performance in the IMPL task. However, the results did not strongly support either of the two accounts. The implications for theories on language acquisition and for tasks developed for examining individual differences are discussed.

Abstract

Children acquire language embedded within the rich social context of interaction. This paper reports on a longitudinal study investigating the developmental relationship between conversational turn‐taking and vocabulary growth in English‐acquiring children (N = 122) followed between 9 and 24 months. Daylong audio recordings obtained every 3 months provided several indices of the language environment, including the number of adult words children heard in their environment and their number of conversational turns. Vocabulary was measured independently via parental report. Growth curve analyses revealed a bidirectional relationship between conversational turns and vocabulary growth, controlling for the amount of words in children’s environments. The results are consistent with theoretical approaches that identify social interaction as a core component of early language acquisition.

Abstract

Children must necessarily process their input in order to learn it, yet the architecture of the developing parsing system and how it interfaces with acquisition is unclear. In the current paper we report experimental and corpus data investigating adult and children's use of morphosyntactic cues for making incremental online predictions of thematic roles in Tagalog, a verb-initial symmetrical voice language of the Philippines. In Study 1, Tagalog-speaking adults completed a visual world eye-tracking experiment in which they viewed pictures of causative actions that were described by transitive sentences manipulated for voice and word order. The pattern of results showed that adults process agent and patient voice differently, predicting the upcoming noun in the patient voice but not in the agent voice, consistent with the observation of a patient voice preference in adult sentence production. In Study 2, our analysis of a corpus of child-directed speech showed that children heard more patient voice- than agent voice-marked verbs. In Study 3, 5-, 7-, and 9-year-old children completed a similar eye-tracking task as used in Study 1. The overall pattern of results suggested that, like the adults in Study 1, children process agent and patient voice differently in a manner that reflects the input distributions, with children developing towards the adult state across early childhood. The results are most consistent with theoretical accounts that identify a key role for input distributions in acquisition and language processing

Abstract

This paper reports on an on-going project designed to collect comparable corpus data on child language and child-directed language in under-researched languages. Despite a long history of cross-linguistic research, there is a severe empirical bias within language acquisition research: Data is available for less than 2% of the world's languages, heavily skewed towards the larger and better-described languages. As a result, theories of language development tend to be grounded in a non-representative sample, and we know little about the acquisition of typologically-diverse languages from different families, regions, or sociocultural contexts. It is very likely that the reasons are to be found in the forbidding methodological challenges of constructing child language corpora under fieldwork conditions with their strict requirements on participant selection, sampling intervals, and amounts of data. There is thus an urgent need for proposals that facilitate and encourage language acquisition research across a wide variety of languages. Adopting a language documentation perspective, we illustrate an approach that combines the construction of manageable corpora of natural interaction with and between children with a sketch description of the corpus data – resulting in a set of comparable corpora and comparable sketches that form the basis for cross-linguistic comparisons.

Abstract

In numerous comprehension studies, across different languages, children have performed worse on object relatives (e.g., the dog that the cat chased) than on subject relatives (e.g., the dog that chased the cat). One possible reason for this is that the test sentences did not exactly match the kinds of object relatives that children typically experience. Adults and children usually hear and produce object relatives with inanimate heads and pronominal subjects (e.g., the car that we bought last year) (cf. Kidd et al., Language and Cognitive Processes 22: 860–897, 2007). We tested young 3-year old German- and English-speaking children with a referential selection task. Children from both language groups performed best in the condition where the experimenter described inanimate referents with object relatives that contained pronominal subjects (e.g., Can you give me the sweater that he bought?). Importantly, when the object relatives met the constraints identified in spoken discourse, children understood them as well as subject relatives, or even better. These results speak against a purely structural explanation for children's difficulty with object relatives as observed in previous studies, but rather support the usage-based account, according to which discourse function and experience with language shape the representation of linguistic structures.

Abstract

Background: Previous research has found that newborn infants can match phonetic information in the lips and voice from as young as ten weeks old. There is evidence that access to visual speech is necessary for normal speech development. Although we have an understanding of this early sensitivity, very little research has investigated older children's ability to speechread whole words. Aims: The aim of this study was to identify aspects of preschool children's linguistic knowledge and processing ability that may contribute to speechreading ability. We predicted a significant correlation between receptive vocabulary and speechreading, as well as phonological working memory to be a predictor of speechreading performance. Methods & Procedures: Seventy-six children (n = 76) aged between 2;10 and 4;11 years participated. Children were given three pictures and were asked to point to the picture that they thought that the experimenter had silently mouthed (ten trials). Receptive vocabulary and phonological working memory were also assessed. The results were analysed using Pearson correlations and multiple regressions. Outcomes & Results: The results demonstrated that the children could speechread at a rate greater than chance. Pearson correlations revealed significant, positive correlations between receptive vocabulary and speechreading score, phonological error rate and age. Further correlations revealed significant, positive relationships between The Children's Test of Non-Word Repetition (CNRep) and speechreading score, phonological error rate and age. Multiple regression analyses showed that receptive vocabulary best predicts speechreading ability over and above phonological working memory. Conclusions & Implications: The results suggest that preschool children are capable of speechreading, and that this ability is related to vocabulary size. This suggests that children aged between 2;10 and 4;11 are sensitive to visual information in the form of audio-visual mappings. We suggest that current and future therapies are correct to include visual feedback as a therapeutic tool; however, future research needs to be conducted in order to elucidate further the role of speechreading in development.

Abstract

Two word-by-word, self-paced reading experiments investigated the speed with which readers were sensitive to discourse-level anomalies. An account arguing for delayed sensitivity (Guzman & Klin, 2000 Guzman, A. E. and Klin, C. M. 2000. Maintaining global coherence in reading: The role of sentence boundaries.. Memory & Cognition, 28: 722–730. [PubMed], [Web of Science ®], [Google Scholar]) was contrasted with one allowing for rapid sensitivity (Myers & O'Brien, 1998 Myers, J. L. and O'Brien, E. J. 1998. Accessing the discourse representation during reading.. Discourse Processes, 26: 131–157. [Taylor & Francis Online], [Web of Science ®], [Google Scholar]). Anomalies related to spatial information (Experiment 1) and character-attribute information (Experiment 2) were examined. Both experiments found that readers displayed rapid sensitivity to the anomalous information. A reading time penalty was observed for the region of text containing the anomalous information. This finding is most compatible with an account of text processing whereby incoming words are rapidly evaluated with respect to prior context. They are not consistent with an account that argues for delayed integration. Results are discussed in light of their implications for competing models of text processing.

Abstract

The ability to represent conditional information is central to human cognition. In two self-paced reading experiments we investigated how readers process counterfactual conditionals (e.g., If Darren had been athletic, he could probably have played on the rugby team ) and indicative conditionals (e.g., If Darren is athletic, he probably plays on the rugby team ). In Experiment 1 we focused on how readers process counterfactual conditional sentences. We found that processing of the antecedent of counterfactual conditionals was rapidly constrained by prior context (i.e., knowing whether Darren was or was not athletic). A reading-time penalty was observed for the critical region of text comprising the last word of the antecedent and the first word of the consequent when the information in the antecedent did not fit with prior context. In Experiment 2 we contrasted counterfactual conditionals with indicative conditionals. For counterfactual conditionals we found the same effect on the critical region as we found in Experiment 1. In contrast, however, we found no evidence that processing of the antecedent of indicative conditionals was constrained by prior context. For indicative conditionals (but not for counterfactual conditionals), the results we report are consistent with the suppositional account of conditionals. We propose that current theories of conditionals need to be able to account for online processing differences between indicative and counterfactual conditionals