Selective,but Only if It Is Free: Children Trust Inaccurate Individuals More when Alternative Sources Are Costly

The present research examines the effect of the costliness of an information source on children's selective learning. In three experiments (total N = 112), 4‐ to 7‐year‐olds were given the opportunity to acquire and endorse information from one of two sources. One source, a computer, was described as always accurate; the other source, a puppet, had a history of either accuracy or inaccuracy. For some children, learning from the computer required giving away stickers. The costliness of the computer clue reduced children's use of this source across all experiments, but its effect on children's use of the puppet varied based on the puppet's accuracy and the type of information learned. Children's trust in the puppet was above chance regardless of the cost of the computer when they were learning generalizable semantic information and the puppet had a history of accuracy. When the puppet was inaccurate or when children learned episodic information, the costliness of the computer significantly increased children's trust in the puppet. Hence, attaching a cost to a preferred knowledge source reduces children's selectivity and increases their trust in sources that they would not otherwise see as desirable. Copyright © 2013 John Wiley & Sons, Ltd.     

Lexical competition in young children's word learning

In two experiments, 1.5-year-olds were taught novel words whose sound patterns were phonologically similar to familiar words (novel neighbors) or were not (novel nonneighbors). Learning was tested using a picture-fixation task. In both experiments, children learned the novel nonneighbors but not the novel neighbors. In addition, exposure to the novel neighbors impaired recognition performance on familiar neighbors. Finally, children did not spontaneously use phonological differences to infer that a novel word referred to a novel object. Thus, lexical competition--inhibitory interaction among words in speech comprehension--can prevent children from using their full phonological sensitivity in judging words as novel. These results suggest that word learning in young children, as in adults, relies not only on the discrimination and identification of phonetic categories, but also on evaluating the likelihood that an utterance conveys a new word.     

Not all is forgotten: Children's associative matrices for features of a word learning episode

Word learning studies traditionally examine the narrow link between words and objects, indifferent to the rich contextual information surrounding objects. This research examined whether children attend to this contextual information and construct an associative matrix of the words, objects, people, and environmental context during word learning. In Experiment 1, preschool-aged children (age: 3;2–5;11 years) were presented with novel words and objects in an animated storybook. Results revealed that children constructed associations beyond words and objects. Specifically, children attended to and had the strongest associations for features of the environmental context but failed to learn word-object associations. Experiment 2 demonstrated that children (age: 3;0–5;8 years) leveraged strong associations for the person and environmental context to support word-object mapping. This work demonstrates that children are especially sensitive to the word learning context and use associative matrices to support word mapping. Indeed, this research suggests associative matrices of the environment may be foundational for children's vocabulary development.     

That's More Like It: Multiple Exemplars Facilitate Word Learning

Previous research indicates learning words facilitates categorisation. The current study explores how categorisation affects word learning. In the current study, we investigated whether learning about a category facilitates retention of newly learned words by presenting 2‐year‐old children with multiple referent selection trials to the same object category. In Experiment 1, children either encountered the same exemplar repeatedly or encountered multiple exemplars across trials. All children did very well on the initial task; however, only children who encountered multiple exemplars retained these mappings after a short delay. Experiment 2 replicated and extended this finding by exploring the effect of within‐category variability on children's word retention. Children encountered either narrow or broad exemplars across trials. Again, all children did very well on the initial task; however, only children who encountered narrow exemplars retained mappings after a short delay. Overall, these data offer strong evidence that providing children with the opportunity to compare across exemplars during fast mapping facilitates retention. Copyright © 2013 John Wiley & Sons, Ltd.     

Illusions of Learning: Irrelevant Emotions Inflate Judgments of Learning

People use assessments of how much they have learned to choose and recommend instructors, seminars, and weekend trips. How do people assess how much they have learned? Recent theorizing has depicted emotion as a cue for learning, and so people may be misled by recent emotional states to infer that they have learned more than they actually have. Four studies showed that people associated emotion with learning and believed, often falsely, that they learned more when in an emotional than unemotional state. Factual lessons were coupled with manipulations of arbitrary, irrelevant emotional states. Participants rated that they learned more after an emotion had been induced than in emotionally neutral control conditions. These differences remained significant after controlling for actual learning as measured by objective tests, which was unaffected by emotion. This illusion of learning caused by emotion was robust with respect to changes of procedure and sample, including whether the emotion came before or after the information to be learned. Alternative explanations were ruled out, including that emotion would intensify ratings generally, that emotion would make incoming information seem particularly personally relevant, that emotion increased engagement in the research, and that illusory learning would depend on retrospective exaggeration of one's prior ignorance. Because irrelevant emotions can increase people's judgments that they have learned something, incidental emotional experiences could increase a person's likelihood of deciding to take another class with a particular instructor, to sign up for another leadership seminar, or to engage in a risky (but emotion‐filled) excursion. Copyright © 2014 John Wiley & Sons, Ltd.     

Consolidation of novel word learning in native English-speaking adults

Sleep has been shown to improve the retention of newly learned words. However, most methodologies have used artificial or foreign language stimuli, with learning limited to word/novel word or word/image pairs. Such stimuli differ from many word-learning scenarios in which definition strings are learned with novel words. Thus, we examined sleep's benefit on learning new words within a native language by using very low-frequency words. Participants learned 45 low-frequency English words and, at subsequent recall, attempted to recall the words when given the corresponding definitions. Participants either learned in the morning with recall in the evening (wake group), or learned in the evening with recall the following morning (sleep group). Performance change across the delay was significantly better in the sleep than the wake group. Additionally, the Levenshtein distance, a measure of correctness of the typed word compared with the target word, became significantly worse following wake, whereas sleep protected correctness of recall. Polysomnographic data from a subsample of participants suggested that rapid eye movement (REM) sleep may be particularly important for this benefit. These results lend further support for sleep's function on semantic learning even for word/definition pairs within a native language.     

Children extend both words and non‐verbal actions to novel exemplars

Markson and Bloom (1997) found that some learning processes involved in children's acquisition of a new word are also involved in their acquisition of a new fact. They argued that these findings provided evidence against a domain‐specific system for word learning. However, Waxman and Booth (2000) found that whereas children quite readily extend newly learned words to novel exemplars within a category, they do not do this with newly learned facts. They therefore argued that because children did not extend some facts in a principled way, word learning and fact learning may result from different domain‐specific processes. In the current study, we argue that facts are a poor comparison in this argument since facts vary in whether they are tied to particular individuals. A more appropriate comparison is a conventional non‐verbal action on an object –‘what we do with things like this’– since they are routinely generalized categorically to new objects. Our study shows that 2¹/₂‐year‐old children extend novel non‐verbal actions to new objects in the same way that they extend novel words to new objects. The findings provide support for the view that word learning represents a unique configuration of more general learning processes.     

Learning new vocabulary during childhood: Effects of semantic training on lexical consolidation and integration

Research suggests that word learning is an extended process, with offline consolidation crucial for the strengthening of new lexical representations and their integration with existing lexical knowledge (as measured by engagement in lexical competition). This supports a dual memory systems account, in which new information is initially sparsely encoded separately from existing knowledge and integrated with long-term memory over time. However, previous studies of this type exploited unnatural learning contexts, involving fictitious words in the absence of word meaning. In this study, 5- to 9-year-old children learned real science words (e.g., hippocampus) with or without semantic information. Children in both groups were slower to detect pauses in familiar competitor words (e.g., hippopotamus) relative to control words 24 h after training but not immediately, confirming that offline consolidation is required before new words are integrated with the lexicon and engage in lexical competition. Children recalled more new words 24 h after training than immediately (with similar improvements shown for the recall and recognition of new word meanings); however, children who were exposed to the meanings during training showed further improvements in recall after 1 week and outperformed children who were not exposed to meanings. These findings support the dual memory systems account of vocabulary acquisition and suggest that the association of a new phonological form with semantic information is critical for the development of stable lexical representations.     

Emotional expression and vocabulary learning in adults and children

A great deal of what we know about the world has not been learned via first-hand observation but thanks to others' testimony. A crucial issue is to know which kind of cues people use to evaluate information provided by others. In this context, recent studies in adults and children underline that informants' facial expressions could play an essential role. To test the importance of the other's emotions in vocabulary learning, we used two avatars expressing happiness, anger or neutral emotions when proposing different verbal labels for an unknown object. Experiment 1 revealed that adult participants were significantly more likely than chance to choose the label suggested by the avatar displaying a happy face over the label suggested by the avatar displaying an angry face. Experiment 2 extended these results by showing that both adults and children as young as 3 years old showed this effect. These data suggest that decision making concerning newly acquired information depends on informant's expressions of emotions, a finding that is consistent with the idea that behavioural intents have facial signatures that can be used to detect another's intention to cooperate.     

Bridging ears and eyes when learning spoken words: On the effects of bilingual experience at 30 months

From the very first moments of their lives, infants selectively attend to the visible orofacial movements of their social partners and apply their exquisite speech perception skills to the service of lexical learning. Here we explore how early bilingual experience modulates children's ability to use visible speech as they form new lexical representations. Using a cross‐modal word‐learning task, bilingual children aged 30 months were tested on their ability to learn new lexical mappings in either the auditory or the visual modality. Lexical recognition was assessed either in the same modality as the one used at learning (‘same modality’ condition: auditory test after auditory learning, visual test after visual learning) or in the other modality (‘cross‐modality’ condition: visual test after auditory learning, auditory test after visual learning). The results revealed that like their monolingual peers, bilingual children successfully learn new words in either the auditory or the visual modality and show cross‐modal recognition of words following auditory learning. Interestingly, as opposed to monolinguals, they also demonstrate cross‐modal recognition of words upon visual learning. Collectively, these findings indicate a bilingual edge in visual word learning, expressed in the capacity to form a recoverable cross‐modal representation of visually learned words.     

Attention to Explicit and Implicit Contrast in Verb Learning

Contrast information could be useful for verb learning, but few studies have examined children's ability to use this type of information. Contrast may be useful when children are told explicitly that different verbs apply, or when they hear two different verbs in a single context. Three studies examine children's attention to different types of contrast as they learn new verbs. Study 1 shows that 3.5-year-olds can use both implicit contrast (“I'm meeking it. I'm koobing it.”) and explicit contrast (“I'm meeking it. I'm not meeking it.”) when learning a new verb, while a control group's responses did not differ from chance. Study 2 shows that even though children at this age who hear explicit contrast statements differ from a control group, they do not reliably extend a newly learned verb to events with new objects. In Study 3, children in three age groups were given both comparison and contrast information, not in blocks of trials as in past studies, but in a procedure that interleaved both cues. Results show that while 2.5-year-olds were unable to use these cues when asked to compare and contrast, by 3.5 years old, children are beginning to be able to process these cues and use them to influence their verb extensions, and by 4.5 years, children are proficient at integrating multiple cues when learning and extending new verbs. Together these studies examine children's use of contrast in verb learning, a potentially important source of information that has been rarely studied.     

Cross‐Situational Learning: An Experimental Study of Word‐Learning Mechanisms

Cross‐situational learning is a mechanism for learning the meaning of words across multiple exposures, despite exposure‐by‐exposure uncertainty as to the word's true meaning. We present experimental evidence showing that humans learn words effectively using cross‐situational learning, even at high levels of referential uncertainty. Both overall success rates and the time taken to learn words are affected by the degree of referential uncertainty, with greater referential uncertainty leading to less reliable, slower learning. Words are also learned less successfully and more slowly if they are presented interleaved with occurrences of other words, although this effect is relatively weak. We present additional analyses of participants’ trial‐by‐trial behavior showing that participants make use of various cross‐situational learning strategies, depending on the difficulty of the word‐learning task. When referential uncertainty is low, participants generally apply a rigorous eliminative approach to cross‐situational learning. When referential uncertainty is high, or exposures to different words are interleaved, participants apply a frequentist approximation to this eliminative approach. We further suggest that these two ways of exploiting cross‐situational information reside on a continuum of learning strategies, underpinned by a single simple associative learning mechanism.     

The relationships among verbal short-term memory, phonological awareness, and new word learning: evidence from typical development and Down syndrome

This study examined the correlates of new word learning in a sample of 64 typically developing children between 5 and 8 years of age and a group of 22 teenagers and young adults with Down syndrome. Verbal short-term memory and phonological awareness skills were assessed to determine whether learning new words involved accurately representing phonological information in memory. Results showed a relationship between verbal short-term memory measures and typically developing individuals’ ability to learn the phonological form of novel words but not their ability to learn the physical referent of new words. Similarly, individuals with Down syndrome showed impaired verbal short-term memory and impaired form but not referent learning. Together, these findings specify the circumstances in which an accurate phonological representation within short-term memory is required for new word learning.     

Effects of contextual diversity on semantic decision and reading aloud: evidence from a word learning study in English as a second language / Efectos de la diversidad contextual en la decisión semántica y la lectura en voz alta: evidencia de un estudio de aprendizaje de palabras en inglés como segundo idioma

This experiment investigated contextual diversity effects on novel word learning in English as a second language (L2). A group of advanced English speakers, whose native language was Spanish, participated in the study. Participants learned the meaning of real but obscure words that were embedded in either two or 12 different sentences and learned over two days (frequency of exposure was kept constant). On day three, participants were tested using reading aloud and semantic decision tasks. The results showed that participants learned the meaning of words in both conditions fairly well as revealed by their accuracy in the semantic decision task. However, words experienced in 12 different contexts generated more accurate and faster reaction times (RTs), suggesting the acquisition of more robust semantic representations. Strikingly, reading latencies were also faster for the 12-sentence condition, which might imply that semantics has an effect on reading newly learned words in English as a second language. These results are discussed and accommodated in view of the DRC and the PDP models of single-word reading.     

Changing Structures in Midstream: Learning Along the Statistical Garden Path

Previous studies of auditory statistical learning have typically presented learners with sequential structural information that is uniformly distributed across the entire exposure corpus. Here we present learners with nonuniform distributions of structural information by altering the organization of trisyllabic nonsense words at midstream. When this structural change was unmarked by low-level acoustic cues, or even when cued by a pitch change, only the first of the two structures was learned. However, both structures were learned when there was an explicit cue to the midstream change or when exposure to the second structure was tripled in duration. These results demonstrate that successful extraction of the structure in an auditory statistical learning task reduces the ability to learn subsequent structures, unless the presence of two structures is marked explicitly or the exposure to the second is quite lengthy. The mechanisms by which learners detect and use changes in distributional information to maintain sensitivity to multiple structures are discussed from both behavioral and computational perspectives.     

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.     

What Is the Buzz About Iconicity? How Iconicity in Caregiver Speech Supports Children's Word Learning

One cue that may facilitate children's word learning is iconicity, or the correspondence between a word's form and meaning. Some have even proposed that iconicity in the early lexicon may serve to help children learn how to learn words, supporting the acquisition of even noniconic, or arbitrary, word–referent associations. However, this proposal remains untested. Here, we investigate the iconicity of caregivers’ speech to young children during a naturalistic free-play session with novel stimuli and ask whether the iconicity of caregivers’ speech facilitates children's learning of the noniconic novel names of those stimuli. Thirty-four 1.5-2-year-olds (19 girls; half monolingual English learners and half bilingual English-Spanish learners) participated in a naturalistic free-play task with their caregivers followed by a test of word-referent retention. We found that caregivers’ use of iconicity, particularly in utterances in which they named the novel stimuli, was associated with the likelihood that children learned that novel name. This result held even when controlling for other factors associated with word learning, such as the concreteness and frequency of words in caregiver speech. Together, the results demonstrate that iconicity not only can serve to help children identify the referent of novel words (as in previous research) but can also support their ability to retain even noniconic word-referent mappings.     

Children’s Judgments of Cultural Expertise: The Influence of Cultural Status and Learning Method

The authors investigated children’s use of cultural status (i.e., foreign vs. American) and learning method to evaluate informants’ expertise in novel cultural practices. Ninety-six 6- to 9-year-olds heard about a foreign informant (i.e., member of an unfamiliar out-group) and an American informant (i.e., member of the participant’s in-group) who each learned about a novel cultural practice differently (i.e., from a person vs. from a book). Participants decided which informant executed the cultural practice better, which informant they would prefer to learn from, and which learning method they would want to use themselves (i.e., learning method preference). Overall, participants endorsed foreign informants over American informants and foreign informants who learned from a person were generally viewed as the preferred option for imparting information in this context. These findings suggest that during the transition to middle childhood, learning context is an important influence on children’s evaluations of cultural identity and learning methods.     

注意和记忆对孤独症儿童词汇发展滞后的影响

孤独症语言障碍的表现之一是词汇发展滞后, 可能与其注意和记忆损伤有关。当前研究结果表明, 孤独症儿童在学习词汇时难以利用社会注意提供的有效信息, 且其注意易受到无关刺激干扰, 这可能导致其形成的物体-词汇的联结不稳定, 影响其进一步将这种联结整合到心理词典并保存在记忆中。未来研究应探究联合注意影响孤独症儿童词汇学习的发展轨迹和机制, 儿童的词汇知识对其词汇记忆的影响, 并关注自然场景中孤独症儿童的词汇学习过程和个体差异。     

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.