Optimal Contrast: Competition Between Two Referents Improves Word Learning

Assessing the language of 2 year-olds: From theory to practice

Early screening for language problems is a priority given the importance of language for success in school and interpersonal relationships. The paucity of reliable behavioral instruments for this age group prompted the development of a new touchscreen language screener for 2-year-olds that relies on language comprehension. Developmental literature guided selection of age-appropriate markers of language disorder risk that are culturally and dialectally neutral and could be reliably assessed. Items extend beyond products of linguistic knowledge (vocabulary and syntax) and tap the process by which children learn language, also known as fast mapping. After piloting an extensive set of items (139), two phases of testing with over 500 children aged 2; 0-2; 11 were conducted to choose the final 40-item set. Rasch analysis was used to select the best fitting and least redundant items. Norms were created based on 270 children. Sufficient test-retest reliability, Cronbach's alpha, and convergent validity with the MB-CDI and PPVT are reported. This quick behavioral measure of language capabilities could support research studies and facilitate the early detection of language problems.

Investigating the contributions of active, playful learning to student interest and educational outcomes

A growing body of evidence from the science of learning demonstrates the educational effectiveness of active, playful learning. Connections are emerging between this pedagogy and the broad set of skills that it promotes in learners, but potential mechanisms behind these relations remain unexplored. This paper offers a commentary based on the science of learning and interest development literature, suggesting that interest may mediate the relation between active, playful learning and student outcomes. This theory is established by identifying principles of active, playful learning that predict interest development and associations between learner interest and key skills for success in the classroom and beyond. Future research should investigate the dynamic relation between active, playful learning, interest, and student achievement over time and across phases of interest while taking a broader set of student outcomes into account.

Background context affects word-object mapping

Children encounter new words across variable and noisy contexts. This variability may affect word learning, but the literature includes discrepant findings. The current experiment investigated one source of these discrepant findings: whether contexts with familiar, nameable objects are associated with less robust label learning. Two year olds were exposed to word-object pairings on variable contexts that either included nameable objects or did not. Target selection was more robust when exposure occurred without other nameable objects. The difference was present immediately, but not after a delay. This study provides the evidence that context effects are context-bound.

Pragmatics aid referent disambiguation and word learning in young children and adults

How do children succeed in learning a word? Research has shown robustly that, in ambiguous labeling situations, young children assume novel labels to refer to unfamiliar rather than familiar objects. However, ongoing debates center on the underlying mechanism: Is this behavior based on lexical constraints, guided by pragmatic reasoning, or simply driven by children's attraction to novelty? Additionally, recent research has questioned whether children's disambiguation leads to long-term learning or rather indicates an attentional shift in the moment of the conversation. Thus, we conducted a pre-registered online study with 2- and 3-year-olds and adults. Participants were presented with unknown objects as potential referents for a novel word. Across conditions, we manipulated whether the only difference between both objects was their relative novelty to the participant or whether, in addition, participants were provided with pragmatic information that indicated which object the speaker referred to. We tested participants' immediate referent selection and their retention after 5 min. Results revealed that when given common ground information both age groups inferred the correct referent with high success and enhanced behavioral certainty. Without this information, object novelty alone did not guide their selection. After 5 min, adults remembered their previous selections above chance in both conditions, while children only showed reliable learning in the pragmatic condition. The pattern of results indicates how pragmatics may aid referent disambiguation and learning in both adults and young children. From early ontogeny on, children's social-cognitive understanding may guide their communicative interactions and support their language acquisition. RESEARCH HIGHLIGHTS: We tested how 2-3-year-olds and adults resolve referential ambiguity without any lexical cues. In the pragmatic context both age groups disambiguated novel word-object-mappings, while object novelty alone did not guide their referent selection. In the pragmatic context, children also showed increased certainty in disambiguation and retained new word-object-mappings over time. These findings contribute to the ongoing debate on whether children learn words on the basis of domain-specific constraints, lower-level associative mechanisms, or pragmatic inferences.

Direct Instruction Improves Word Learning for Children With Developmental Language Disorder

PURPOSE

The current study compared the effects of direct instruction versus indirect exposure on multiple aspects of novel word learning for children with developmental language disorder (DLD) and children with typical language development (TLD).

METHOD

Participants included 36 children with DLD and 45 children with TLD. All children were in the first grade and 6-8 years of age (Mdn = 7 years; 2 months). Using a between-subjects design, children were randomly assigned to be exposed to novel words and their unfamiliar referents via either direct instruction (each referent presented in isolation with an explicit goal of learning) or indirect exposure (multiple referents presented with the goal of answering yes/no questions).

RESULTS

In alternative forced-choice measures of recognition, children with DLD were less accurate than their TLD peers in linking words to referents, encoding semantic categories for words, and encoding detailed representations of word forms. These differences in word learning were accounted for by a constellation of cognitive measures, including receptive vocabulary, phonological memory, visuospatial memory, and sustained attention. All children were similarly accurate in retaining word forms over a 24- to 48-hr delay. Children with TLD were more accurate in all aspects of word learning following direct instruction compared to indirect exposure. Benefits from direct instruction were observed for children with DLD in link and semantic, but not word form, learning.

CONCLUSIONS

These results suggest that vocabulary interventions with direct instruction can help children with DLD learn some, but not all, aspects of novel words. Additional support is necessary to help children with DLD encode rich phonological representations.

Prior Exposure and Toddlers' Sleep-Related Memory for Novel Words

Children can easily link a novel word to a novel, unnamed object—something referred to as fast mapping. Despite the ease and speed with which children do this, their memories for novel fast-mapped words can be poor unless they receive memory supports such as further exposure to the words or sleep. Axelsson, Swinton, Winiger, and Horst (2018) found that 2.5-year-old children who napped after fast mapping had better retention of novel words than children who did not nap. Retention declined for those who did not nap. The children received no memory supports and determined the word-object mappings independently. Previous studies report enhanced memories after sleeping in children and adults, but the napping children’s retention in the Axelsson et al. study remained steady across time. We report a follow-up investigation where memory supports are provided after fast mapping to test whether memories would be enhanced following napping. Children’s retention of novel words improved and remained greater than chance; however, there was no nap effect with no significant difference between the children who napped and those who did not. These findings suggest that when memory supports are provided, retention improves, and the word–object mappings remain stable over time. When memory traces are weak and labile, such as after fast mapping, without further memory supports, sleeping soon after helps stabilise and prevent decay of word–object mappings.

Patterns of mutual exclusivity and retention: A study of monolingual and bilingual 2-year-olds

When children learn their native language, they tend to treat objects as if they only have one label-a principle known as mutual exclusivity. However, bilingual children are faced with a different cognitive challenge-they need to learn to associate two labels with one object. In the present study, we compared bilingual and monolingual 24-month-olds' performance on a challenging and semi-naturalistic forced-choice referent selection task and retention test. Overall, both language groups performed similarly on referent selection but differed on retention. Specifically, while monolingual infants showed some retention, bilingual infants performed at chance and significantly worse than their monolingual peers.

Processes and pathways in development via digital media: Examples from word learning

Word learning unfolds over multiple, cascading pathways which support in-the-moment processing and learning. The process is refined with each exposure to a word, and exposures to new words occur across a variety of forms and contexts. However, as children are exposed to more and more digital media, the ways in which children encounter, learn, and build on their vocabulary is also shifting. These shifts represent changes in context, content, and at the level of the child that can lead to negative outcomes. Less work, however, has discussed what these differences mean for how things change in the underlying developmental cascade and learning processes. Here, we suggest that the increasing presence of digital media may shift the developmental pathways for learning (the chain of events that support future learning) but not necessarily the developmental processes (the mechanisms underlying learning). Moreover, the interaction of the two may lead to different behavior and outcomes for learning in a digital era. We argue it is imperative for researchers to not only study how digital media differs from everyday learning, but directly measure if the well-worn pathways, processes, and variables found with decades of research with real items translate to a digital media era.

Within and Across Language Predictors of Word Learning Processes in Dual Language Learners

This study investigated the relation between Dual Language Learners' (N = 90) vocabulary and grammar comprehension and word learning processes in preschool (aged 3-through-5 years). Of interest was whether: (a) performance in Spanish correlated with performance in English within each domain; and (b) comprehension predicted novel word learning within and across languages. Dual-language experience was evaluated as a potential moderator. Hierarchical linear modeling revealed stronger predictive associations within each language than across languages. Across languages, results varied by experience and domain. Structural sensitivity theory suggests exposure to two languages heightens awareness of parameters along which languages vary and provides a framework for interpreting complex associations within and across languages. Knowledge from one language may influence learning in both.

24-Month-olds and over remember novel object names after a single learning event

In the context of word learning, it is commonly assumed that repetition is required for young children to form and maintain in memory an association between a novel word and its corresponding object. For instance, at 2 years of age, children are able to disambiguate word-related situations in one shot but are not able to further retain this newly acquired knowledge. It has been proposed that multiple fast-mapping experiences would be required to promote word retention or that the inferential reasoning needs to be accompanied by explicit labeling of the target. We hypothesized that when 2-year-olds simply encounter an unambiguous learning context, word learning may be fast and maintained in time. We also assumed that, under this condition, even a single exposure to an object would be sufficient to form a memory trace of its name that would survive a delay. To test these hypotheses, 2- and 4-year-olds were ostensively taught three arbitrary word-object pairs using a 15-s video sequence during which each object was manually displayed and labeled three times in a row. Retention was measured after a 30-min distractive period using a forced-choice procedure. Our results provide evidence that declarative memory does not need repetition to be formed and maintained, for at least a 30-min period, by children as young as 2 years. This finding suggests that the mechanisms required for extremely rapid and robust word acquisition not only are present in preschoolers with developed language and cognitive skills but also are already operative at a younger age.

Comparing cross-situational word learning, retention, and generalisation in children with autism and typical development

Word learning is complicated by referential ambiguity - there are often multiple potential targets for a newly-heard word. While typically developing (TD) children can accurately infer word meanings from cross-situational statistics, specific difficulties tracking word-object co-occurrences may contribute to language impairments in autism spectrum disorder (ASD). Here, we investigate cross-situational word learning as an integrated system including mapping, retention, and generalisation in both typical development and autism. In Study 1, children with ASD were as accurate at disambiguating the meanings of novel words from statistical correspondences as TD controls matched on receptive vocabulary. In Study 2, both populations spontaneously utilised social and non-social attentional cues to facilitate and accelerate their mapping of word-referent relationships. Across Studies 1 and 2, both groups retrieved and generalised word-referent representations with impressive and comparable accuracy. Although children with ASD performed very similarly to TD children on measures of learning accuracy, they were significantly slower to identify correct referents under both cued and non-cued learning conditions. These findings indicate that mechanisms supporting cross-situational word learning, and the relationships between them, are not qualitatively atypical in language-delayed children with ASD. However, the increased time required to generate correct responses suggests that these mechanisms may be less efficient, potentially impacting learning in natural environments where visual and auditory stimuli are presented rapidly. Our data support claims that word learning in the longer term is driven by the gradual accumulation of word-object associations over multiple learning instances and could potentially inform the development of interventions designed to scaffold word learning.

Sometimes it is better to know less: How known words influence referent selection and retention in 18- to 24-month-old children

Young children are surprisingly good word learners. Despite their relative lack of world knowledge and limited vocabularies, they consistently map novel words to novel referents and, at later ages, show retention of these new word-referent pairs. Prior work has implicated the use of mutual exclusivity constraints and novelty biases, which require that children use knowledge of well-known words to disambiguate uncertain naming situations. The current study, however, presents evidence that weaker vocabulary knowledge during the initial exposure to a new word may be better for retention of new mappings. Children aged 18-24 months selected referents for novel words in the context of foil stimuli that varied in their lexical strength and novelty: well-known items (e.g., shoe), just-learned weakly known items (e.g., wif), and completely novel items. Referent selection performance was significantly reduced on trials with weakly known foil items. Surprisingly, however, children subsequently showed above-chance retention for novel words mapped in the context of weakly known competitors compared with those mapped with strongly known competitors or with completely novel competitors. We discuss implications for our understanding of word learning constraints and how children use known words and novelty during word learning.

Adult Fast-Mapping Memory Research Is Based on a Misinterpretation of Developmental-Word-Learning Data

Fast mapping is often used to refer to children’s remarkable ability to learn the meanings of new words with minimal exposure and in ambiguous contexts. It is one thing to claim that children are capable of learning words this way; it is another to claim that this ability relies on a specific fast-mapping neurocognitive mechanism that is critical for early word learning. Yet that claim has recently been made in adult memory research and used as a theoretical justification for research into an adult fast-mapping mechanism. In this review, we explain why the existence of such a mechanism in children is not supported by developmental research and explore the implications for adult fast-mapping data and research.

Insights From Crossing Research Silos on Visual and Auditory Attention

Many learning tasks that children encounter necessitate the ability to direct and sustain attention to key aspects of the environment while simultaneously tuning out irrelevant features. This is challenging for at least two reasons: (a) The ability to regulate and sustain attention follows a protracted developmental time course, and (b) children spend much of their time in environments not optimized for learning-homes and schools are often chaotic, cluttered, and noisy. Research on these issues is often siloed; that is, researchers tend to examine the relationship among attention, distraction, and learning in only the auditory or the visual domain, but not both together. We provide examples in which auditory and visual aspects of learning each have strong implications for the other. Research examining how visual information and auditory information are distracting can benefit from cross-fertilization. Integrating across research silos informs our understanding of attention and learning, yielding more efficacious guidance for caregivers, educators, developers, and policymakers.

Taking their eye off the ball: How shyness affects children's attention during word learning

The current study tests the hypothesis that shy children's reduced word learning is partly due to an effect of shyness on attention during object labeling. A sample of 20- and 26-month-old children (N = 32) took part in a looking-while-listening task in which they saw sets of familiar and novel objects while hearing familiar or novel labels. Overall, children increased attention to familiar objects when hearing their labels, and they divided their attention equally between the target and competitors when hearing novel labels. Critically, shyness reduced attention to the target object regardless of whether the heard label was novel or familiar. When children's retention of the novel word-object mappings was tested after a delay, it was found that children who showed increased attention to novel objects during labeling showed better retention. Taken together, these findings suggest that shyer children perform less well than their less shy peers on measures of word learning because their attention to the target object is dampened. Thus, this work presents evidence that shyness modulates the low-level processes of visual attention that unfold during word learning.

Why would a special FM process exist in adults, when it does not appear to exist in children?

Cooper Greve, and Henson (this issue)  caution restraint before accepting that a fast mapping (FM) process exists in adults. We welcome this, but would also add that the original rationale for studying FM in adults is not currently supported by developmental research. Despite the claims of several adult FM researchers, there is little evidence from developmental word learning research for a special hippocampus-independent FM process critical for children's word learning.

Let's Chat: On-Screen Social Responsiveness Is Not Sufficient to Support Toddlers' Word Learning From Video

Joint engagement with a speaker is one cue children may use to establish that an interaction is relevant to them and worthy of attention. People on pre-recorded video cannot engage contingently with a viewer in shared experiences, possibly leading to deficits in learning from video relative to learning from responsive face-to-face encounters. One hundred and thirty two toddlers (24 and 30 months old) were offered referential social cues disambiguating a novel word's meaning in one of four conditions: responsive live (a speaker was present and engaged with children); unresponsive video (a speaker on video looked at the camera and smiled at scripted times); unresponsive live (although present, the speaker behaved as she did on the unresponsive video), and responsive video (a speaker on closed-circuit video engaged with children, as in video chat). Children of both ages reliably learned the word in the responsive live condition, and older children (30 months) learned in the unresponsive live condition. Neither group learned in the responsive or unresponsive video conditions. The results show that the addition of communicative social cues to the video presentation via video chat was not sufficient to support learning in this case. Rather, toddlers' transfer and generalization of words presented on video chat may depend on other contextual factors, such as co-viewers who scaffold their learning. Live, responsive video as implemented in this and prior studies is compared, with implications for the use of video chat via the Internet with young children.

Accessing the Inaccessible: Redefining Play as a Spectrum

Defining play has plagued researchers and philosophers for years. From describing play as an inaccessible concept due to its complexity, to providing checklists of features, the field has struggled with how to conceptualize and operationalize “play.” This theoretical piece reviews the literature about both play and learning and suggests that by viewing play as a spectrum – that ranges from free play (no guidance or support) to guided play and games (including purposeful adult support while maintaining playful elements), we better capture the true essence of play and explain its relationship to learning. Insights from the Science of Learning allow us to better understand why play supports learning across social and academic domains. By changing the lens through which we conceptualize play, we account for previous findings in a cohesive way while also proposing new avenues of exploration for the field to study the role of learning through play across age and context.

The effect of shyness on children's formation and retention of novel word-object mappings

This study set out to examine whether shyness, an aversion to novelty and unfamiliar social situations, can affect the processes that underlie early word learning. Twenty-four-month-old children (n =32) were presented with sets of one novel and two familiar objects, and it was found that shyer children were less likely to select a novel object as the referent of a novel label. Furthermore, not-shy children then showed evidence of retaining these novel mappings, but shy children did not. These findings suggest that shy children's aversion to novelty and to the unfamiliar context can impact on their word learning.

All Tapped Out: Touchscreen Interactivity and Young Children's Word Learning

Touchscreen devices differ from passive screen media in promoting physical interaction with events on the screen. Two studies examined how young children's screen-directed actions related to self-regulation (Study 1) and word learning (Study 2). In Study 1, 30 2-year-old children's tapping behaviors during game play were related to their self-regulation, measured using Carlson's snack task: girls and children with high self-regulation tapped significantly less during instruction portions of an app (including object labeling events) than did boys and children with low self-regulation. Older preschoolers (N = 47, aged 4-6 years) tapped significantly less during instruction than 2-year-olds did. Study 2 explored whether the particular way in which 170 children (2-4 years of age) interacted with a touchscreen app affected their learning of novel object labels. Conditions in which children tapped or dragged a named object to move it across the screen required different amounts of effort and focus, compared to a non-interactive (watching) condition. Age by sex interactions revealed a particular benefit of dragging (a motorically challenging behavior) for preschool girls' learning compared to that of boys, especially for girls older than age 2. Boys benefited more from watching than dragging. Children from low socioeconomic status families learned more object names when dragging objects versus tapping them, possibly because tapping is a prepotent response that does not require thoughtful attention. Parents and industry experts should consider age, sex, self-regulation, and the physical requirements of children's engagement with touchscreens when designing and using educational content.

Moving Word Learning to a Novel Space: A Dynamic Systems View of Referent Selection and Retention

Theories of cognitive development must address both the issue of how children bring their knowledge to bear on behavior in-the-moment, and how knowledge changes over time. We argue that seeking answers to these questions requires an appreciation of the dynamic nature of the developing system in its full, reciprocal complexity. We illustrate this dynamic complexity with results from two lines of research on early word learning. The first demonstrates how the child's active engagement with objects and people supports referent selection via memories for what objects were previously seen in a cued location. The second set of results highlights changes in the role of novelty and attentional processes in referent selection and retention as children's knowledge of words and objects grows. Together this work suggests that understanding systems for perception, action, attention, and memory, and their complex interaction, is critical to understand word learning. We review recent literature that highlights the complex interactions between these processes in cognitive development and point to critical issues for future work.

Reprint of "Young children's referent selection is guided by novelty for both words and actions"

Young children are biased to select novel, name-unknown objects as referents of novel labels and to similarly favor novel, action-unknown objects as referents of novel actions. What process underlies these common behaviors? In the case of word learning, children may be driven by a novelty bias favoring novel objects as referents. Our study investigated this bias further by investigating whether novelty also affects children's selection of novel objects when a new action is given. In a pre-exposure session, 40 3- and 4-year-olds were shown eight novel objects for 1min. In subsequent referent selection trials, children were shown two pre-exposed objects and one super-novel object and either heard a novel name or saw a novel action. The super-novel object was selected significantly more than the pre-exposed objects on both word and action trials. Our data add to the growing literature suggesting that an endogenous attentional bias to novelty plays a role in children's referent selection and demonstrates further parallels between word and action learning.

Near or far: The effect of spatial distance and vocabulary knowledge on word learning

The current study investigated the role of spatial distance in word learning. Two-year-old children saw three novel objects named while the objects were either in close proximity to each other or spatially separated. Children were then tested on their retention for the name-object associations. Keeping the objects spatially separated from each other during naming was associated with increased retention for children with larger vocabularies. Children with a lower vocabulary size demonstrated better retention if they saw objects in close proximity to each other during naming. This demonstrates that keeping a clear view of objects during naming improves word learning for children who have already learned many words, but keeping objects within close proximal range is better for children at earlier stages of vocabulary acquisition. The effect of distance is therefore not equal across varying vocabulary sizes. The influences of visual crowding, cognitive load, and vocabulary size on word learning are discussed.

Putting Education in “Educational” Apps

Children are in the midst of a vast, unplanned experiment, surrounded by digital technologies that were not available but 5 years ago. At the apex of this boom is the introduction of applications (“apps”) for tablets and smartphones. However, there is simply not the time, money, or resources available to evaluate each app as it enters the market. Thus, “educational” apps—the number of which, as of January 2015, stood at 80,000 in Apple’s App Store (Apple, 2015)—are largely unregulated and untested. This article offers a way to define the potential educational impact of current and future apps. We build upon decades of work on the Science of Learning, which has examined how children learn best. From this work, we abstract a set of principles for two ultimate goals. First, we aim to guide researchers, educators, and designers in evidence-based app development. Second, by creating an evidence-based guide, we hope to set a new standard for evaluating and selecting the most effective existing children’s apps. In short, we will show how the design and use of educational apps aligns with known processes of children’s learning and development and offer a framework that can be used by parents and designers alike. Apps designed to promote active, engaged, meaningful, and socially interactive learning—four “pillars” of learning—within the context of a supported learning goal are considered educational.

Contextual repetition facilitates word learning via fast mapping

The current study explores whether contextual repetition during fast mapping facilitates word learning. Three-year-old children completed fast mapping and test trials using a touchscreen computer. For half of the children, the non-targets (competitors) repeated across learning trials and for other children there was no repetition. All children received the same test trials. Children who experienced contextual repetition, that is, children for whom the competitors repeated during the initial fast mapping task, demonstrated word learning. These data demonstrate that children's word learning is facilitated by the presence of extraneous yet predictable information in the initial fast mapping task.

The type, but not the amount, of information available influences toddlers' fast mapping and retention of new words

PURPOSE

The authors of this study examined whether the type and number of word-learning cues affect how children infer and retain word-meaning mappings and whether the use of these cues changes with age.

METHOD

Forty-eight 18- to 36-month-old children with typical language participated in a fast-mapping task in which 6 novel words were presented with 3 types of cues to the words' referents, either singly or in pairs. One day later, children were tested for retention of the novel words.

RESULTS

By 24 months of age, children correctly inferred the referents of the novel words at a significant level. Children retained the meanings of words at a significant rate by 30 months of age. Children retained the first 3 of the 6 word-meaning mappings by 24 months of age. For both fast mapping and retention, the efficacy of different cue types changed with development, but children were equally successful whether the novel words were presented with 1 or 2 cues.

CONCLUSION

The type of information available to children at fast mapping affects their ability to both form and retain word-meaning associations. Providing children with more information in the form of paired cues had no effect on either fast mapping or retention.

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.