Lexical Acquisition Research Articles

1P1-E14 Saliencyに基づく能動性を利用した語彙獲得

1P1-E14 Saliencyに基づく能動性を利用した語彙獲得

Lexical acquisition in elementary science classes.

The purpose of this study was to further researchers' understanding of lexical acquisition in the beginning primary schoolchild by investigating word learning in small-group elementary science classes. Two experiments were conducted to examine the role of semantic scaffolding (e.g., use of synonymous terms) and physical scaffolding (e.g., pointing to referents) in children's acquisition of novel property terms. Children's lexical knowledge was assessed using multiple tasks (naming, comprehension, and definitional). Children struggled to acquire meanings of adjectives without semantic or physical scaffolding (Experiment 1), but they were successful in acquiring extensive lexical knowledge when offered semantic scaffolding (Experiment 2). Experiment 2 also shows that semantic scaffolding used in combination with physical scaffolding helped children acquire novel adjectives and that children who correctly named pictures of adjectives had acquired definitions.

The Role of Embodied Intention in Early Lexical Acquisition

We examine the influence of inferring interlocutors' referential intentions from their body movements at the early stage of lexical acquisition. By testing human participants and comparing their performances in different learning conditions, we find that those embodied intentions facilitate both word discovery and word-meaning association. In light of empirical findings, the main part of this article presents a computational model that can identify the sound patterns of individual words from continuous speech, using nonlinguistic contextual information, and employ body movements as deictic references to discover word-meaning associations. To our knowledge, this work is the first model of word learning that not only learns lexical items from raw multisensory signals to closely resemble infant language development from natural environments, but also explores the computational role of social cognitive skills in lexical acquisition.

The emergence of links between lexical acquisition and object categorization: a computational study

Language is about symbols, and those symbols must be grounded in the physical world. Children learn to associate language with sensorimotor experiences during their development. In light of this, we first provide a computational account of how words are mapped to their perceptually grounded meanings. Moreover, the main part of this work proposes and implements a computational model of how word learning influences the formation of object categories to which those words refer. This model simulates the bi-directional relationship between word and object category learning: (1) object categorization provides mental representations of meanings that are mapped to words to form lexical items; (2) linguistic labels help object categorization by providing additional teaching signals; and (3) these two learning processes interplay with each other and form a developmental feedback loop. Compared with the method that performs these two tasks separately, our model shows promising improvements in both word-to-world mapping and perceptual categorization, suggesting a unified view of lexical and category learning in an integrative framework. Most importantly, this work provides a cognitively plausible explanation of the mechanistic nature of early word learning and object learning from co-occurring multisensory data.

English-learning Infants' Segmentation of Verbs from Fluent Speech

Two experiments sought to extend the demonstration of English-learning infants' abilities to segment nouns from fluent speech to a new lexical class: verbs. Moreover, we explored whether two factors previously shown to influence noun segmentation, stress pattern (strong-weak or weak-strong) and type of initial phoneme (consonant or vowel), also influence verb segmentation. Our results establish the early emergence of verb segmentation in English: by 13.5 months for strong-weak consonant- or vowel-initial verbs and for weak-strong consonant-initial verbs; and by 16.5 months for weak-strong verbs beginning with a vowel. This generalizes previous reports of early segmentation to a new lexical class, thereby providing additional evidence that segmentation is likely to contribute to lexical acquisition. The effects of stress pattern and onset type found are similar to those previously obtained for nouns, in that verbs with a weak-strong stress pattern and verbs beginning with a vowel appear to be at a disadvantage in segmentation. Finally, we present prosodic analyses that suggest a possible effect of prosodic boundary and pitch accent distribution on segmentation. These prosodic differences potentially explain a developmental lag in verb segmentation observed in the present study compared to earlier findings for noun segmentation.

What's in a diary? Di-EL first words

Children with hearing loss and their families are now presenting for early intervention support and guidance at increasingly younger ages. At present there is a paucity of research that informs teachers about early language development in the child with hearing loss. Di-EL First Words (Di-EL) is a diary technique through which parents record their child's first 100 single words, in collaboration with teachers. This paper demonstrates, through case studies, how data from a child's diary can be used to monitor and investigate rate of lexical acquisition, lexical content and the emergence of word combinations in three children with profound hearing loss. This information is important if teachers are to know if, when, and how to promote early language development in children with hearing loss.

Language learning

Language learning

Deep lexical acquisition of verb–particle constructions

This paper proposes a range of techniques for extracting English verb-particle constructions from raw text corpora, complete with valence information. We propose four basic methods, based on the output of a POS tagger, chunker, chunk grammar and dependency parser, respectively. We then present a combined classifier which we show to consolidate the strengths of the component methods.

The Relationship between Negotiated Interaction, Learner Uptake, and Lexical Acquisition in Task-Based Computer-Mediated Communication

The present study builds on recent uptake research (Ellis, Basturkmen, & Loewen, 2001a, 2001b; Lyster & Ranta, 1997) by exploring the relationship between negotiated interaction, a type of focus on form episode, and learner uptake. The study explores whether a negotiation routine's complexity affects learner uptake and if this uptake affects lexical acquisition in a synchronous computer-mediated environment. The data are chatscripts of task-based computer-mediated communication (CMC) interaction among intermediate-level learners of English (n = 24). Results suggest that the complexity of negotiation routines does not influence learner uptake. Findings also suggest that there is no relationship between degree of uptake (none, unsuccessful, and successful) and the acquisition of target lexical items. These results suggest a possible diminished role for uptake in SLA in a CMC environment. The pedagogical application of these findings includes a word of caution to classroom teachers to adjust their expectations about the relationship between learner uptake and acquisition. In attempting to explain the acquisition of target vocabulary items during task-based CMC interaction, teachers should focus on the nuances of negotiated interaction as well as more subtle indications of acquisition rather than learner uptake per se.

Conceptual Information Permeates Word Learning in Infancy.

Three experiments document that conceptual knowledge influences lexical acquisition in infancy. A novel target object was initially labeled with a novel word. In both yes-no (Experiment 1) and forced-choice (Experiment 2) tasks, 2-year-olds' subsequent extensions were mediated by the conceptual description of the targets. When targets were described as artifacts, infants extended on the basis of shape. When targets were described as animates, infants extended on the basis of both shape and texture. Experiment 3 revealed similar results for 1.5-year-olds. These results challenge the notion that expectations in word learning (e.g., the "shape bias") (a) emerge late and (b) rest entirely on correlations between perceptual object features and words. Instead, the results indicate that both perceptual and conceptual information permeate word learning in infancy.

The Emerging Lexicon of Children With Phonological Delays

The effects of phonotactic constraints (i.e., the status of a sound as correctly or incorrectly articulated) and phonotactic probability (i.e., the likelihood of a sound sequence) on lexical acquisition have been investigated independently. This study investigated the interactive influence of phonotactic constraints and phonotactic probability on lexical acquisition in 3 groups of children: children with functional phonological delays (PD), phonology-matched, younger, typically developing children (PM), and age-/vocabulary-matched typically developing peers (AVM). Sixty-eight children participated in a multitrial word-learning task involving nonwords varying in phonotactic constraints (IN vs. OUT) and phonotactic probability (common vs. rare). Correct and error responses were analyzed. Results indicated that OUT sound sequences were learned more rapidly than IN sound sequences. This suggests that OUT sounds may be salient because they represent only a small subset of the child's sound system. The effect of phonotactic probability varied across groups: Children with PD showed a common sound sequence disadvantage, younger PM children showed a common sound sequence advantage, and AVM children showed no effect. Moreover, error analyses indicated that children with PD had particular difficulty creating lexical representations and associations between lexical and semantic representations when learning common sound sequences. Children with PD may rely more heavily on lexical representations to learn new words or may have difficulty learning common sound sequences because of the high degree of similarity between these sequences and other known words. Finally, the effect of phonotactic probability was consistent across IN and OUT sound sequences, suggesting that the lexical representation of both correctly articulated and misarticulated words is based on the adult-target pronunciation.

Effects of sentence writing in second language lexical acquisition

This study compared the effects of writing new words in sentences with word picture repetition learning alone. Second language (L2) Spanish learners attempted to learn 24 new Spanish words in one of two conditions while viewing word picture pairs. In Experiment 1, in the no sentence writing condition, the participants viewed 4 repetitions of each word for 6 seconds each. In the sentence writing condition, they viewed 1 repetition of each word for 48 seconds and were asked to write the word in a Spanish sentence. In Experiment 2, the participants were shown one repetition of each word for 24 seconds in both the sentence writing and no sentence writing conditions. Immediate and delayed posttests on productive vocabulary knowledge were administered in both experiments. Scores were submitted to analyses of variance. Condition and time were independent variables. Target word production was scored based on syllables and whole words produced. Results of both experiments indicated strong negative effects for the sentence writing conditions, suggesting that sentence writing can inhibit word form learning during the initial stages of L2 lexical acquisition.

Language learning

Language learning

Early lexical development in a self-organizing neural network

In this paper we present a self-organizing neural network model of early lexical development called DevLex. The network consists of two self-organizing maps (a growing semantic map and a growing phonological map) that are connected via associative links trained by Hebbian learning. The model captures a number of important phenomena that occur in early lexical acquisition by children, as it allows for the representation of a dynamically changing linguistic environment in language learning. In our simulations, DevLex develops topographically organized representations for linguistic categories over time, models lexical confusion as a function of word density and semantic similarity, and shows age-of-acquisition effects in the course of learning a growing lexicon. These results match up with patterns from empirical research on lexical development, and have significant implications for models of language acquisition based on self-organizing neural networks.

The Role of Grammar in Second Language Lexical Processing

The role of grammatical knowledge in second language (L2) lexical processing is far from clear. Providing evidence from a recent introspective study, this paper seeks to demonstrate the significant contribution that such knowledge can make to inferring the meanings of unfamiliar words while reading, and to possible consequent acquisition of L2 vocabulary. The findings of the study point to the importance of learners’ knowledge of grammar in L2 lexical processing and L2 vocabulary acquisition process, and lends support to the intrinsic value of grammar instruction.

Do children acquire dense neighborhoods? An investigation of similarity neighborhoods in lexical acquisition

This study tests the claim that children acquire collections of phonologically similar word forms, namely, dense neighborhoods. Age of acquisition (AoA) norms were obtained from two databases: parent report of infant and toddler production and adult self-ratings of AoA. Neighborhood density, word frequency, word length, Density×Frequency and Density×Length were analyzed as potential predictors of AoA using linear regression. Early acquired words were higher in density, higher in word frequency, and shorter in length than late acquired words. Significant interactions provided evidence that the lexical factors predicting AoA varied, depending on the type of word being learned. The implication of these findings for lexical acquisition and language learning are discussed.

Lexical Development of Thai Children at 0;9-2;0: A Cross-Sectional Study

This study investigates lexical development of Thai children at 0;9-2;0. Based on the MacArthur Communicative Development Inventories: Words and Gestures, 1989 (CDI), a Thai version of the CDI word checklist was developed. Following a cross-sectional research design, parents of 180 children were asked to report their children's lexical development. Four main aspects of lexical development were investigated: the onset of development, cumulative vocabularies, lexical categories of words acquired, and the relationship between comprehension and production in lexical acquisition. It was found that individual variation plays an important role in children's lexical development. Instead of pinpointing the exact age of the onset of development, a tentative range of onset is reported about 0;9-1;3. Although children's vocabulary items increase over time, it was found that there were two distinct types of increase: gradual and rapid. The gradual increase was found from 0;9-1;6, and 1;9-2;0. The rapid increase, at about 1;6, represents a period of vocabulary explosion. It was found that Thai children's lexicon is "noun" dominant. From an examination of the relationship between word comprehension and production, it was found that comprehension precedes production at the onset of lexical development. However, data from this study also demonstrate that at about the period of vocabulary explosion, some words are comprehended only after they have been produced. It is also suggested that lexical development should also be investigated using a longitudinal research design, because data from a longitudinal study can indicate the development of individual children and might demonstrate more clearly development in terms of individual variation.

Is age at implant the only factor that counts? The influence of working memory on lexical and grammatical development in children with cochlear implants

In this study, we explored the influence of time factors (age at implant, time with cochlear implant and age), complex working memory and phonological short-term memory on lexical and grammatical development in congenitally deaf children with cochlear implants. Fifteen children (aged 5 years 4 months to 11 years 5 months) were examined with the use of several linguistic and cognitive measures after a minimum of 18 months of implant use. Phonological short-term memory was assessed with non-word repetition, where the percentage of correctly repeated consonants and vowels was counted. For the assessment of lexical acquisition, a novel word learning task was administered. Receptive and expressive grammar was tested. Our results corroborate earlier findings on the influence of phonological short-term memory on novel word learning. The percentage of vowels correctly produced in non-word repetition was more important in this group than age at implant, not only for novel word learning, but also for receptive and expressive grammar.

Assessment of Language Skills in Young Children with Profound Hearing Loss under Two Years of Age.

This article presents an initial evaluation of a technique known as the Diary of Early Language (Di-EL), designed to obtain data about early lexical development in young children with profound hearing loss using cochlear implants, hearing aids, or both. The validity of the Di-EL, a parent report technique, was examined through comparisons with other measures of language development. Lexical data reported by parents using the Di-EL was found to agree with that reported by the same parents for the same children using the MacArthur Communicative Development Inventories (CDI), although some differences in the lexical items were noted. Rate of lexical acquisition on the Di-EL was found to correlate highly with that measured by the CDI and with expressive language skills as measured by the Rossetti Infant Toddler Language Scale, suggesting that the Di-EL is a valid measure of early lexical progress. These results are discussed with reference to other diary studies, along with research and clinical applications of the Di-EL.

Learning new objects with new names: Cognitive and neural correlates of lexical acquisition

Learning new objects with new names: Cognitive and neural correlates of lexical acquisition