Beyond fast mapping: young children's extensions of novel words and novel facts

L. Markson and P. Bloom (1997) concluded that there was evidence against a dedicated system for word learning on the basis of their finding that children remembered a novel word and a novel fact equally well. However, a word-learning system involves more than recognition memory; it must also provide a means to guide the extension of words to additional exemplars, and words and facts may differ with regard to extendibility. Two studies are reported in which 2-4-year-old children learned novel words and novel facts for unfamiliar objects and then were asked to extend the words and facts to additional exemplars of the training objects. In both studies, children extended the novel word to significantly more category members than they extended the novel fact. The results show that by 2 years of age, children honor the necessary extendibility of novel count nouns but are uncertain about the extendibility of arbitrary facts.     

Is It a Name or a Fact? Disambiguation of Reference Via Exclusivity and Pragmatic Reasoning

Adults reason by exclusivity to identify the meanings of novel words. However, it is debated whether, like children, they extend this strategy to disambiguate other referential expressions (e.g., facts about objects). To further inform this debate, this study tested 41 adults on four conditions of a disambiguation task: label/label, fact/fact, label/fact, and fact/label (Scofield & Behrend, 2007 ). Participants also provided a verbal explanation for their referent selections to tease apart the underlying processes. Results indicated that adults successfully discerned the target object in the label/label and label/fact condition, yet not the remaining two conditions. Verbal reports indicated that the strategy utilized to disambiguate differed depending upon communicative context. These findings confirm that the tendency to reason by exclusivity becomes restricted to word‐learning situations with growing linguistic and communicative experience.     

Familiar words can serve as a semantic seed for syntactic bootstrapping

Young children can exploit the syntactic context of a novel word to narrow down its probable meaning. But how do they learn which contexts are linked to which semantic features in the first place? We investigate if 3‐ to 4‐year‐old children (n = 60) can learn about a syntactic context from tracking its use with only a few familiar words. After watching a 5‐min training video in which a novel function word (i.e., ‘ko’) replaced either personal pronouns or articles, children were able to infer semantic properties for novel words co‐occurring with the newly learned function word (i.e., objects vs. actions). These findings implicate a mechanism by which a distributional analysis, associated with a small vocabulary of known words, could be sufficient to identify some properties associated with specific syntactic contexts.     

The evocative power of words: activation of concepts by verbal and nonverbal means

A major part of learning a language is learning to map spoken words onto objects in the environment. An open question is what are the consequences of this learning for cognition and perception? Here, we present a series of experiments that examine effects of verbal labels on the activation of conceptual information as measured through picture verification tasks. We find that verbal cues, such as the word "cat," lead to faster and more accurate verification of congruent objects and rejection of incongruent objects than do either nonverbal cues, such as the sound of a cat meowing, or words that do not directly refer to the object, such as the word "meowing." This label advantage does not arise from verbal labels being more familiar or easier to process than other cues, and it does extends to newly learned labels and sounds. Despite having equivalent facility in learning associations between novel objects and labels or sounds, conceptual information is activated more effectively through verbal means than through nonverbal means. Thus, rather than simply accessing nonverbal concepts, language activates aspects of a conceptual representation in a particularly effective way. We offer preliminary support that representations activated via verbal means are more categorical and show greater consistency between subjects. These results inform the understanding of how human cognition is shaped by language and hint at effects that different patterns of naming can have on conceptual structure.     

Children learn words easier when they are interested in the category to which the word belongs

The overall pattern of vocabulary development is relatively similar across children learning different languages. However, there are considerable differences in the words known to individual children. Historically, this variability has been explained in terms of differences in the input. Here, we examine the alternate possibility that children's individual interest in specific natural categories shapes the words they are likely to learn – a child who is more interested in animals will learn a new animal name easier relative to a new vehicle name. Two‐year‐old German‐learning children (N = 39) were exposed to four novel word–object associations for objects from four different categories. Prior to the word learning task, we measured their interest in the categories that the objects belonged to. Our measure was pupillary change following exposure to familiar objects from these four categories, with increased pupillary change interpreted as increased interest in that category. Children showed more robust learning of word–object associations from categories they were more interested in relative to categories they were less interested in. We further found that interest in the novel objects themselves influenced learning, with distinct influences of both category interest and object interest on learning. These results suggest that children's interest in different natural categories shapes their word learning. This provides evidence for the strikingly intuitive possibility that a child who is more interested in animals will learn novel animal names easier than a child who is more interested in vehicles.     

Offline consolidation supersedes prior knowledge benefits in children's (but not adults’) word learning

Prior linguistic knowledge is proposed to support the acquisition and consolidation of new words. Adults typically have larger vocabularies to support word learning than children, but the developing brain shows enhanced neural processes that are associated with offline memory consolidation. This study investigated contributions of prior knowledge to initial word acquisition and consolidation at different points in development, by teaching children and adults novel words (e.g., ballow) that varied in the number of English word‐form “neighbours” (e.g., wallow, bellow). Memory for the novel word‐forms was tested immediately after training, the next day and 1 week later, to assess the time‐course of prior knowledge contributions. Children aged 7–9 years (Experiments 1, 3) and adults (Experiment 2) recalled words with neighbours better than words without neighbours when tested immediately after training. However, a period of offline consolidation improved overall recall and reduced the influence of word‐form neighbours on longer term memory. These offline consolidation benefits were larger in children than adults, supporting theories that children have a greater propensity for consolidating phonologically distinctive language information. Local knowledge of just a single word‐form neighbour was enough to enhance learning, and this led to the individual differences in word recall that were related to adults’ global vocabulary ability. The results support the proposal that the relative contributions of different learning mechanisms change across the lifespan, and highlight the importance of testing theoretical models of word learning in the context of development.     

Children acquire the later‐greater principle after the cardinal principle

Many have proposed that the acquisition of the cardinal principle (CP) is a result of the discovery of the numerical significance of the order of the number words in the count list. However, this need not be the case. Indeed, the CP does not state anything about the numerical significance of the order of the number words. It only states that the last word of a correct count denotes the numerosity of the counted set. Here, we test whether the acquisition of the CP involves the discovery of the later‐greater principle – that is, that the order of the number words corresponds to the relative size of the numerosities they denote. Specifically, we tested knowledge of verbal numerical comparisons (e.g., Is ‘ten’ more than ‘six’?) in children who had recently learned the CP. We find that these children can compare number words between ‘six’ and ‘ten’ only if they have mapped them onto non‐verbal representations of numerosity. We suggest that this means that the acquisition of the CP does not involve the discovery of the correspondence between the order of the number words and the relative size of the numerosities they denote.     

Lexical‐processing efficiency leverages novel word learning in infants and toddlers

Children who rapidly recognize and interpret familiar words typically have accelerated lexical growth, providing indirect evidence that lexical processing efficiency (LPE) is related to word‐learning ability. Here we directly tested whether children with better LPE are better able to learn novel words. In Experiment 1, 17‐ and 30‐month‐olds were tested on an LPE task and on a simple word‐learning task. The 17‐month‐olds’ LPE scores predicted word learning in a regression model, and only those with relatively good LPE showed evidence of learning. The 30‐month‐olds learned novel words quite well regardless of LPE, but in a more difficult word‐learning task (Experiment 2), their LPE predicted word‐learning ability. These findings suggest that LPE supports word‐learning processes, especially when learning is difficult.     

New Word Acquisition in Children: Examining the Contribution of Verbal Short‐term Memory to Lexical and Semantic Levels of Learning

A variety of evidence suggests that human vocabulary acquisition and verbal short‐term ability are related. The aim of this study was to investigate the learning of new lexical and semantic representation in 7 to 12 years old children selected on the basis of their poor working memory capacity. A deep characterization of the short‐term memory (STM) capacities has been carried out through a series of tasks derived from recent STM models tapping STM, language and attentional processes. Participants experienced a three conditions word learning task designed to reflect lexical learning, semantic learning and lexical–semantic learning capacities. Other aspects of the learning such as the learning rate and the word length effect were evaluated. The experimental participants scored more poorly than controls on lexical learning, and this deficit was associated with the serial order STM and the attentional capacities. The current study also highlighted that neither the experimental group nor the control group took advantage in lexical learning of semantic information supplement. Our results suggest that children with verbal STM problems learn a smaller number of new words but present a similar way of learning than children without verbal STM problems. Copyright © 2013 John Wiley & Sons, Ltd.     

The intersensory origins of word‐comprehension: an ecological–dynamic systems view

How do infants begin to understand spoken words? Recent research suggests that word comprehension develops from the early detection of intersensory relations between conventionally paired auditory speech patterns (words) and visible objects or actions. More importantly, in keeping with dynamic systems principles, the findings suggest that word comprehension develops from a dynamic and complementary relationship between the organism (the infant) and the environment (language addressed to the infant). In addition, parallel findings from speech and non‐speech studies of intersensory perception provide evidence for domain general processes in the development of word comprehension. These research findings contrast with the view that a lexical acquisition device with specific lexical principles and innate constraints is required for early word comprehension. Furthermore, they suggest that learning of word–object relations is not merely an associative process. The data support an alternative view of the developmental process that emphasizes the dynamic and reciprocal interactions between general intersensory perception, selective attention and learning in infants, and the specific characteristics of maternal communication.     

Sensitivity to sampling in Bayesian word learning

We report a new study testing our proposal that word learning may be best explained as an approximate form of Bayesian inference (Xu & Tenenbaum, in press). Children are capable of learning word meanings across a wide range of communicative contexts. In different contexts, learners may encounter different sampling processes generating the examples of word-object pairings they observe. An ideal Bayesian word learner could take into account these differences in the sampling process and adjust his/her inferences about word meaning accordingly. We tested how children and adults learned words for novel object kinds in two sampling contexts, in which the objects to be labeled were sampled either by a knowledgeable teacher or by the learners themselves. Both adults and children generalized more conservatively in the former context; that is, they restricted the label to just those objects most similar to the labeled examples when the exemplars were chosen by a knowledgeable teacher, but not when chosen by the learners themselves. We discuss how this result follows naturally from a Bayesian analysis, but not from other statistical approaches such as associative word-learning models.     

The Effect of Retrieval Practice in Primary School Vocabulary Learning

The testing effect refers to the finding that retrieval practice leads to better long‐term retention than additional study of course material. In the present study, we examined whether this finding generalizes to primary school vocabulary learning. We also manipulated the word learning context. Children were introduced to 20 words by listening to a story in which novel words were embedded (story condition) or by listening to isolated words (word pairs condition). The children practised the meaning of 10 words by retrieval practice and 10 words by restudy. After 1 week, they completed a cued recall test and a multiple choice test. Words learned by retrieval practice were recalled better than words learned by additional study, but there was no difference in recognition. Furthermore, the children in the word pairs condition outperformed the children in the story condition. These results show that retrieval practice may improve vocabulary learning in children. Copyright © 2013 John Wiley & Sons, Ltd.     

The origins of word learning: Brain responses of 3‐month‐olds indicate their rapid association of objects and words

The present study explored the origins of word learning in early infancy. Using event‐related potentials (ERP) we monitored the brain activity of 3‐month‐old infants when they were repeatedly exposed to several initially novel words paired consistently with each the same initially novel objects or inconsistently with different objects. Our results provide strong evidence that these young infants extract statistic regularities in the distribution of the co‐occurrences of objects and words extremely quickly. The data suggest that this ability is based on the rapid formation of associations between the neural representations of objects and words, but that the new associations are not retained in long‐term memory until the next day. The type of brain response moreover indicates that, unlike in older infants, in 3‐month‐olds a semantic processing stage is not involved. Their ability to combine words with meaningful information is caused by a primary learning mechanism that enables the formation of proto‐words and acts as a precursor for the acquisition of genuine words.     

Reverse production effect: children recognize novel words better when they are heard rather than produced

This research investigates the effect of production on 4.5‐ to 6‐year‐old children's recognition of newly learned words. In Experiment 1, children were taught four novel words in a produced or heard training condition during a brief training phase. In Experiment 2, children were taught eight novel words, and this time training condition was in a blocked design. Immediately after training, children were tested on their recognition of the trained novel words using a preferential looking paradigm. In both experiments, children recognized novel words that were produced and heard during training, but demonstrated better recognition for items that were heard. These findings are opposite to previous results reported in the literature with adults and children. Our results show that benefits of speech production for word learning are dependent on factors such as task complexity and the developmental stage of the learner.     

A Computational Model of the Self‐Teaching Hypothesis Based on the Dual‐Route Cascaded Model of Reading

The self‐teaching hypothesis describes how children progress toward skilled sight‐word reading. It proposes that children do this via phonological recoding with assistance from contextual cues, to identify the target pronunciation for a novel letter string, and in so doing create an opportunity to self‐teach new orthographic knowledge. We present a new computational implementation of self‐teaching within the dual‐route cascaded (DRC) model of reading aloud, and we explore how decoding and contextual cues can work together to enable accurate self‐teaching under a variety of circumstances. The new model (ST‐DRC) uses DRC’s sublexical route and the interactivity between the lexical and sublexical routes to simulate phonological recoding. Known spoken words are activated in response to novel printed words, triggering an opportunity for orthographic learning, which is the basis for skilled sight‐word reading. ST‐DRC also includes new computational mechanisms for simulating how contextual information aids word identification, and it demonstrates how partial decoding and ambiguous context interact to achieve irregular‐word learning. Beyond modeling orthographic learning and self‐teaching, ST‐DRC’s performance suggests new avenues for empirical research on how difficult word classes such as homographs and potentiophones are learned.     

Testing a word is not a test of word learning

Although vocabulary acquisition requires children learn names for multiple things, many investigations of word learning mechanisms teach children the name for only one of the objects presented. This is problematic because it is unclear whether children's performance reflects recall of the correct name–object association or simply selection of the only object that was singled out by being the only object named. Children introduced to one novel name may perform at ceiling as they are not required to discriminate on the basis of the name per se, and appear to rapidly learn words following minimal exposure to a single word. We introduced children to four novel objects. For half the children, only one of the objects was named and for the other children, all four objects were named. Only children introduced to one word reliably selected the target object at test. This demonstration highlights the over-simplicity of one-word learning paradigms and the need for a shift in word learning paradigms where more than one word is taught to ensure children disambiguate objects on the basis of their names rather than their degree of salience.     

Two‐year‐olds are vigilant of others’ non‐verbal cues to credibility

Data from three experiments provide the first evidence that children, at least as young as age two, are vigilant of others’ non‐verbal cues to credibility, and flexibly use these cues to facilitate learning. Experiment 1 revealed that 2‐ and 3‐year‐olds prefer to learn about objects from someone who appears, through non‐verbal cues, to be confident in performing actions on those objects than from someone who appears uncertain when performing actions on those objects. Experiment 2 revealed that when 2‐year‐olds observe only one model perform a single action, either confidently or unconfidently, they do not use the model’s level of confidence in this single instance to influence their learning. Experiment 3 revealed that 2‐year‐olds will use a single model’s level of confidence to guide their learning if they have observed that the model has a history of being either consistently confident or consistently uncertain. These findings reveal that young children selectively alter their learning based on others’ non‐verbal cues of credibility, and underscore the importance of an early sensitivity to socio‐cognitive cues for human learning and development.     

How parents introduce new words to young children: The influence of development and developmental disorders

This study documents how parents weave new words into on-going interactions with children who are just beginning to speak. Dyads with typically developing toddlers and with young children with autism spectrum disorder and Down syndrome (n = 56, 23, and 29) were observed using a Communication Play Protocol during which parents could use novel words to refer to novel objects. Parents readily introduced both labels and sound words even when their child did not respond expressively or produce the words. Results highlight both how parents act in ways that may facilitate their child's appreciation of the relation between a new word and its referent and how they subtly adjust their actions to suit their child's level of word learning and specific learning challenges.     

发展性阅读障碍儿童阅读中的眼跳定位缺陷：基于新词学习的实验证据

通过与生理年龄匹配儿童比较新词重复学习中眼跳定位模式变化的异同, 探讨发展性阅读障碍儿童在新词学习中的眼跳定位是否存在缺陷。以发展性阅读障碍儿童和生理年龄匹配儿童为被试, 采用重复学习新词范式, 结果发现：(1)与生理年龄匹配组相比, 发展性阅读障碍儿童跳入新词的眼跳距离较短、首次注视落点位置更靠近词首; (2)生理年龄匹配组儿童利用学习次数调节新词眼跳定位模式的能力高于发展性阅读障碍儿童, 即随着新词学习次数的增加, 生理年龄匹配组儿童跳入和跳出新词的眼跳距离随之增长, 首次注视落点位置更靠近词中心; 相比之下, 发展性阅读障碍儿童仅在跳出新词的眼跳距离上有所增长, 但增加幅度也显著小于生理年龄匹配组。结果表明, 发展性阅读障碍儿童在新词学习中的眼跳定位, 及利用学习次数对眼跳定位的调节上均表现出一定缺陷。     

Do ‘literate’ pigeons (<Emphasis Type="Italic">Columba livia</Emphasis>) show mirror-word generalization?

Many children pass through a mirror stage in reading, where they write individual letters or digits in mirror and find it difficult to correctly utilize letters that are mirror images of one another (e.g., b and d). This phenomenon is thought to reflect the fact that the brain does not naturally discriminate left from right. Indeed, it has been argued that reading acquisition involves the inhibition of this default process. In the current study, we tested the ability of literate pigeons, which had learned to discriminate between 30 and 62 words from 7832 nonwords, to discriminate between words and their mirror counterparts. Subjects were sensitive to the left–right orientation of the individual letters, but not the order of letters within a word. This finding may reflect the fact that, in the absence of human-unique top-down processes, the inhibition of mirror generalization may be limited.