When is a word in good company for learning?

Although identifying the referents of single words is often cited as a key challenge for getting word learning off the ground, it overlooks the fact that young learners consistently encounter words in the context of other words. How does this company help or hinder word learning? Prior investigations into early word learning from children's real-world language input have yielded conflicting results, with some influential findings suggesting an advantage for words that keep a diverse company of other words, and others suggesting the opposite. Here, we sought to triangulate the source of this conflict, comparing different measures of diversity and approaches to controlling for correlated effects of word frequency across multiple languages. The results were striking: while different diversity measures on their own yielded conflicting results, once nonlinear relationships with word frequency were controlled, we found convergent evidence that contextual consistency supports early word learning. RESEARCH HIGHLIGHTS: The words children learn occur in a sea of other words. The company words keep ranges from highly variable to highly consistent and circumscribed. Prior findings conflict over whether variability versus consistency helps early word learning. Accounting for correlated effects of word frequency resolved the conflict across multiple languages. Results reveal convergent evidence that consistency helps early word learning.

To sleep or not to sleep? No effect of sleep on contextual word learning in younger adults.

This study investigated the effect of sleep on novel word learning through reading context. Seventy-four healthy young adults attended two testing sessions, with either overnight sleep (sleep group) or daytime wakefulness (wake group) occurring between the sessions. At the initial learning session, participants identified the hidden meanings of novel words embedded within sentence contexts and were subsequently tested on their recognition of the novel word meanings. A recognition test was also conducted at the delayed session. The analyses revealed comparable recognition of novel word meanings for the sleep and wake group at both the initial and the delayed session, indicating that there was no benefit of sleep compared with wakefulness for novel word learning through context. Overall, this study highlights the critical influence of encoding method on sleep-dependent learning, where not all forms of word learning appear to benefit from sleep for consolidation.

Automatic selection of coordinate systems for learning relative and absolute spatial concepts.

Robots employed in homes and offices need to adaptively learn spatial concepts using user utterances. To learn and represent spatial concepts, the robot must estimate the coordinate system used by humans. For example, to represent spatial concept "left," which is one of the relative spatial concepts (defined as a spatial concept depending on the object's location), humans use a coordinate system based on the direction of a reference object. As another example, to represent spatial concept "living room," which is one of the absolute spatial concepts (defined as a spatial concept that does not depend on the object's location), humans use a coordinate system where a point on a map constitutes the origin. Because humans use these concepts in daily life, it is important for the robot to understand the spatial concepts in different coordinate systems. However, it is difficult for robots to learn these spatial concepts because humans do not clarify the coordinate system. Therefore, we propose a method (RASCAM) that enables a robot to simultaneously estimate the coordinate system and spatial concept. The proposed method is based on ReSCAM+O, which is a learning method for relative spatial concepts based on a probabilistic model. The proposed method introduces a latent variable that represents a coordinate system for simultaneous learning. This method can simultaneously estimate three types of unspecified information: coordinate systems, reference objects, and the relationship between concepts and words. No other method can estimate all these three types. Experiments using three different coordinate systems demonstrate that the proposed method can learn both relative and absolute spatial concepts while accurately selecting the coordinate system. The proposed approach can be beneficial for service robots to flexibly understand a new environment through the interactions with humans.

Spanish-learning infants switch from a vowel to a consonant bias during the first year of life.

The consonant bias is evidenced by a greater reliance on consonants over vowels in lexical processing. Although attested during adulthood for most Roman and Germanic languages (e.g., French, Italian, English, Dutch), evidence on its development suggests that the native input modulates its trajectory. French and Italian learners exhibit an early switch from a higher reliance on vowels at 5 and 6 months of age to a consonant bias by the end of the first year. This study investigated the developmental trajectory of this bias in a third Romance language unexplored so far-Spanish. In a central visual fixation procedure, infants aged 5, 8½, and 12 months were tested in a word recognition task. In Experiment 1, infants preferred listening to frequent words (e.g., leche, milk) over nonwords (e.g., machi) at all ages. Experiment 2 assessed infants' listening times to consonant and vowel alterations of the words used in Experiment 1. Here, 5-month-olds preferred listening to consonant alterations, whereas 12-month-olds preferred listening to vowel alterations, suggesting that 5-month-olds' recognition performance was more affected by a vowel alteration (e.g., leche →lache), whereas 12-month-olds' recognition performance was more affected by a consonant alteration (e.g., leche →keche). These findings replicate previous findings in Italian and French and generalize them to a third Romance language (Spanish). As such, they support the idea that specific factors common to Romance languages might be driving an early consonant bias in lexical processing.

Emotional Valence Precedes Semantic Maturation of Words: A Longitudinal Computational Study of Early Verbal Emotional Anchoring.

We present a longitudinal computational study on the connection between emotional and amodal word representations from a developmental perspective. In this study, children's and adult word representations were generated using the latent semantic analysis (LSA) vector space model and Word Maturity methodology. Some children's word representations were used to set a mapping function between amodal and emotional word representations with a neural network model using ratings from 9-year-old children. The neural network was trained and validated in the child semantic space. Then, the resulting neural network was tested with adult word representations using ratings from an adult data set. Samples of 1210 and 5315 words were used in the child and the adult semantic spaces, respectively. Results suggested that the emotional valence of words can be predicted from amodal vector representations even at the child stage, and accurate emotional propagation was found in the adult word vector representations. In this way, different propagative processes were observed in the adult semantic space. These findings highlight a potential mechanism for early verbal emotional anchoring. Moreover, different multiple linear regression and mixed-effect models revealed moderation effects for the performance of the longitudinal computational model. First, words with early maturation and subsequent semantic definition promoted emotional propagation. Second, an interaction effect between age of acquisition and abstractness was found to explain model performance. The theoretical and methodological implications are discussed.

A meta-analysis of infants' word-form recognition.

Recognizing word forms is an important step on infants' way toward mastering their native language. The present study takes a meta-analytic approach to assess overarching questions on the literature of early word-form recognition. Specifically, we investigated the extent to which there is cross-linguistic evidence for an early recognition lexicon, and how it may be influenced by infant age, language background, and familiarity of the selected stimuli (approximated by parent-reported word knowledge). Our meta-analysis-with open data access on metalab.stanford.edu-was based on 32 experiments in 16 different published or unpublished studies on infants 5-15 months of age. We found an overall significant effect of word-form familiarity on infants' responses. This effect increased with age and was higher for infants learning Romance languages than other languages. We further found that younger, but not older, infants showed higher effect sizes for more familiar word lists. These insights should help researchers plan future studies on word-form recognition.

Contrasting lexical biases in bilingual English-Mandarin speech: Verb-biased mothers, but noun-biased toddlers.

Is noun dominance in early lexical acquisition a widespread or a language-specific phenomenon? Thirty Singaporean bilingual English-Mandarin learning toddlers and their mothers were observed in a mother-child play interaction. For both English and Mandarin, toddlers' speech and reported vocabulary contained more nouns than verbs across book reading and toy playing. In contrast, their mothers' speech contained more verbs than nouns in both English and Mandarin but differed depending on the context of the interaction. Although toddlers demonstrated a noun bias for both languages, the noun bias was more pronounced in English than in Mandarin. Together, these findings support early noun dominance as a widespread phenomenon in the lexical acquisition debate but also provide evidence that language specificity also plays a minor role in children's early lexical development.

Let's Talk About Emotions: the Development of Children's Emotion Vocabulary from 4 to 11 Years of Age.

Learning to use language in an adult-like way is a long-lasting process. This may particularly apply to complex conceptual domains such as emotions. The present study examined children's and adults' patterns of emotion word usage regarding their convergence and underlying semantic dimensions, and the factors influencing the ease of emotion word learning. We assessed the production of emotion words by 4- to 11-year-old children (N = 123) and 27 adults (M = 37 years) using a vignette test. We found that the older the children, the more emotion words they produced. Moreover, with increasing age, children's pattern of emotion word usage converged with adult usage. The analysis for semantic dimensions revealed one clear criterion-the differentiation of positive versus negative emotions-for all children and adults. We further found that broad covering emotion words are produced earlier and in a more adult-like way.

Word skipping during the lexical acquisition process.

During reading, most words are identified in the fovea through a direct fixation; however, readers also identify some words in the parafovea without directly fixating them. This word skipping process is influenced by many lexical and visual factors including word length, launch position, frequency, and predictability. Although these factors are well understood, there is some disagreement about the process that leads to word skipping and the degree to which skipped words are processed. The purpose of this study was to investigate the word skipping process when readers are exposed to novel words in an incidental lexical acquisition paradigm. Participants read 18 three-letter novel words (i.e., pru, cho) in three different informative contexts each while their eye movements were monitored. They then completed a surprise test of their orthographic and semantic acquisition and a spelling skill assessment. Mixed-effects models indicated that participants learned spellings and meanings of words at the same rate regardless of the number of times that they were skipped. However, word skipping rates increased across the three exposures and reading times decreased. Results indicate that readers appear to process skipped words to the same degree as fixated words. However, this may be due to a more cautious skipping process used during lexical acquisition of unfamiliar words compared to processing of already known words.

Early lexical acquisition in the Wichi language.

This research brings new evidence on early lexical acquisition in Wichi, an under-studied indigenous language in which verbs occupy a privileged position in the input and in conjunction with nouns are characterized by a complex and rich morphology. Focusing on infants ranging from one- to three-year-olds, we analyzed the parental report of infants' vocabulary (Study 1) and naturalistic speech samples of children and their caregivers (Study 2). Results reveal that: (1) although verbs predominate in the linguistic input, children's lexicons favor nouns over verbs; (2) children's early noun-advantage decreases, coming into closer alignment with the patterns in the linguistic input at a MLU of 1.5; and (3) this early transition is temporally related to children's increasing productive command over the grammatical categories that characterize the morphology of both nouns and verbs. These findings emphasize the early effects of language-specific properties of the input, broadening the vantage point from which to view the lexical acquisition process.

White noise facilitates new-word learning from context.

Listening to white noise may facilitate cognitive performance, including new word learning, for some individuals. This study investigated whether auditory white noise facilitates the learning of novel written words from context in healthy young adults. Sixty-nine participants were required to determine the meaning of novel words placed within sentence contexts during a silent reading task. Learning was performed either with or without white noise, and recognition of novel word meanings was tested immediately after learning and after a short delay. Immediate recognition accuracy for learned novel word meanings was higher in the noise group relative to the no noise group, however this effect was no longer evident at the delayed recognition test. These findings suggest that white noise has the capacity to facilitate meaning acquisition from context, however further research is needed to clarify its capacity to improve longer-term retention of meaning.

Token Frequency Effects in Homophone Production: An Elicitation Study.

In natural production, adults differentiate homophones prosodically as a function of the frequency of their intended meaning. This study compares adult and child productions of homophones to determine whether prosodic differentiation of homophones changes over development. Using a picture-based story-completion paradigm, isolated tokens of homophones were elicited from English-learning children and adult native English speakers. These tokens were measured for duration, vowel duration, pitch, pitch range, and vowel quality. Results indicate that less frequent meanings of homophones are longer in duration than their more frequent counterparts in both adults and children. No other measurement differed as a function of meaning frequency. As speakers of all ages produce longer tokens of lower frequency homophones, homophone differentiation does not change over development, but is included in children's early lexicons. These findings indicate that production planning processes alone may not fully account for differences in homophone duration, but rather that the differences could be learned and represented from experience even in the early stages of lexical acquisition.

Is the L2 lexicon different from the L1 lexicon? Evidence from novel word lexicalization.

Studies on the representation of newly learned words in the native language show that after repeated sessions of learning, novel words produce less form priming than nonwords when they are used as primes in a masked priming experiment. This suggests that the newly learned words have established lexical representations, and therefore start to behave more like real words than nonwords (Qiao & Forster, 2013). Since adult language learning normally happens in a foreign language context rather than in the native language context, it is important to see whether similar results could be obtained if bilingual subjects were taught novel words in their second language (L2) rather than their first language (L1). The current experiment explores this issue using the same procedure and materials as used in the L1 experiment. Results show that in contrast to the nonsignificant priming observed with the L1 speakers, L2 speakers show enhanced facilitatory priming after the same training process. In addition, a significant facilitatory priming effect is also obtained with real words as primes, suggesting that the L1 and L2 lexicons might work in rather different ways. One possibility is that the L2 lexicon is not represented in the same type of memory system as the L1 lexicon, rather it is represented in a system where competitive effects are not observed.

Cross-Situational Learning with Bayesian Generative Models for Multimodal Category and Word Learning in Robots.

In this paper, we propose a Bayesian generative model that can form multiple categories based on each sensory-channel and can associate words with any of the four sensory-channels (action, position, object, and color). This paper focuses on cross-situational learning using the co-occurrence between words and information of sensory-channels in complex situations rather than conventional situations of cross-situational learning. We conducted a learning scenario using a simulator and a real humanoid iCub robot. In the scenario, a human tutor provided a sentence that describes an object of visual attention and an accompanying action to the robot. The scenario was set as follows: the number of words per sensory-channel was three or four, and the number of trials for learning was 20 and 40 for the simulator and 25 and 40 for the real robot. The experimental results showed that the proposed method was able to estimate the multiple categorizations and to learn the relationships between multiple sensory-channels and words accurately. In addition, we conducted an action generation task and an action description task based on word meanings learned in the cross-situational learning scenario. The experimental results showed that the robot could successfully use the word meanings learned by using the proposed method.

Levodopa enhances explicit new-word learning in healthy adults: a preliminary study.

OBJECTIVE: While the role of dopamine in modulating executive function, working memory and associative learning has been established; its role in word learning and language processing more generally is not clear. This preliminary study investigated the impact of increased synaptic dopamine levels on new-word learning ability in healthy young adults using an explicit learning paradigm. METHOD: A double-blind, placebo-controlled, between-groups design was used. Participants completed five learning sessions over 1 week with levodopa or placebo administered at each session (five doses, 100 mg). Each session involved a study phase followed by a test phase. Test phases involved recall and recognition tests of the new (non-word) names previously paired with unfamiliar objects (half with semantic descriptions) during the study phase. RESULTS: The levodopa group showed superior recall accuracy for new words over five learning sessions compared with the placebo group and better recognition accuracy at a 1-month follow-up for words learnt with a semantic description. CONCLUSIONS: These findings suggest that dopamine boosts initial lexical acquisition and enhances longer-term consolidation of words learnt with semantic information, consistent with dopaminergic enhancement of semantic salience.

Richness of information about novel words influences how episodic and semantic memory networks interact during lexicalization.

The complementary learning systems account of declarative memory suggests two distinct memory networks, a fast-mapping, episodic system involving the hippocampus, and a slower semantic memory system distributed across the neocortex in which new information is gradually integrated with existing representations. In this study, we investigated the extent to which these two networks are involved in the integration of novel words into the lexicon after extensive learning, and how the involvement of these networks changes after 24h. In particular, we explored whether having richer information at encoding influences the lexicalization trajectory. We trained participants with two sets of novel words, one where exposure was only to the words' phonological forms (the form-only condition), and one where pictures of unfamiliar objects were associated with the words' phonological forms (the picture-associated condition). A behavioral measure of lexical competition (indexing lexicalization) indicated stronger competition effects for the form-only words. Imaging (fMRI) results revealed greater involvement of phonological lexical processing areas immediately after training in the form-only condition, suggesting that tight connections were formed between novel words and existing lexical entries already at encoding. Retrieval of picture-associated novel words involved the episodic/hippocampal memory system more extensively. Although lexicalization was weaker in the picture-associated condition, overall memory strength was greater when tested after a 24hour delay, probably due to the availability of both episodic and lexical memory networks to aid retrieval. It appears that, during lexicalization of a novel word, the relative involvement of different memory networks differs according to the richness of the information about that word available at encoding.

Words and possible words in early language acquisition.

In order to acquire language, infants must extract its building blocks-words-and master the rules governing their legal combinations from speech. These two problems are not independent, however: words also have internal structure. Thus, infants must extract two kinds of information from the same speech input. They must find the actual words of their language. Furthermore, they must identify its possible words, that is, the sequences of sounds that, being morphologically well formed, could be words. Here, we show that infants' sensitivity to possible words appears to be more primitive and fundamental than their ability to find actual words. We expose 12- and 18-month-old infants to an artificial language containing a conflict between statistically coherent and structurally coherent items. We show that 18-month-olds can extract possible words when the familiarization stream contains marks of segmentation, but cannot do so when the stream is continuous. Yet, they can find actual words from a continuous stream by computing statistical relationships among syllables. By contrast, 12-month-olds can find possible words when familiarized with a segmented stream, but seem unable to extract statistically coherent items from a continuous stream that contains minimal conflicts between statistical and structural information. These results suggest that sensitivity to word structure is in place earlier than the ability to analyze distributional information. The ability to compute nontrivial statistical relationships becomes fully effective relatively late in development, when infants have already acquired a considerable amount of linguistic knowledge. Thus, mechanisms for structure extraction that do not rely on extensive sampling of the input are likely to have a much larger role in language acquisition than general-purpose statistical abilities.

Convencionalidade na aquisição de verbos: estudo comparativo das análises dicotômicas e contínuas / Conventionality in verb acquisition: a comparative study of dichotomic and continuous analysis

A convencionalidade é um princípio pragmático da aquisição lexical que possibilita a adequação das palavras ao contexto. O objetivo deste estudo foi comparar dois tipos de análise - dicotômica e contínua - da convencionalidade dos verbos, obtidos por meio de uma tarefa de nomeação de ações composta por 17 vídeos breves, aplicada a 37 crianças com idades entre 2:0 e 3:0 e 43 crianças entre 3:1 e 4:5. Foram comparadas duas análises: (1) dicotômica - verbos classificados como não convencionais ou convencionais; e (2) contínua - escores entre 1 e 5, obtidos por escala likert. Os resultados mostraram que as duas formas de análise diferenciam os grupos etários, embora a análise contínua apresente vantagens, revelando mais detalhes do desenvolvimento do léxico de verbos.(AU)

Conventionality is a pragmatic principle of lexical acquisition which makes the adequacy of words to the context possible. The aim of this study was to compare dichotomic and continuous analysis in the classification of this pragmatic principle. The data were obtained by an actions naming task composed of 17 brief videos, applied to 37 children aged between 2:0 and 3:0 and 43 children aged between 3:1 and 4:5. Two analyses were compared: (1) dichotomic - verbs classified as non conventional or conventional; and (2) continuous, scores between 1 and 5, obtained using a Likert scale. The results showed that the two kinds of analysis distinguish the age groups, although the continuous analysis presents advantages, revealing more details about the verbs lexical development.(AU)

Convencionalidade na aquisição de verbos: estudo comparativo das análises dicotômicas e contínuas / Conventionality in verb acquisition: a comparative study of dichotomic and continuous analysis

A convencionalidade é um princípio pragmático da aquisição lexical que possibilita a adequação das palavras ao contexto. O objetivo deste estudo foi comparar dois tipos de análise - dicotômica e contínua - da convencionalidade dos verbos, obtidos por meio de uma tarefa de nomeação de ações composta por 17 vídeos breves, aplicada a 37 crianças com idades entre 2:0 e 3:0 e 43 crianças entre 3:1 e 4:5. Foram comparadas duas análises: (1) dicotômica - verbos classificados como não convencionais ou convencionais; e (2) contínua - escores entre 1 e 5, obtidos por escala likert. Os resultados mostraram que as duas formas de análise diferenciam os grupos etários, embora a análise contínua apresente vantagens, revelando mais detalhes do desenvolvimento do léxico de verbos.

Conventionality is a pragmatic principle of lexical acquisition which makes the adequacy of words to the context possible. The aim of this study was to compare dichotomic and continuous analysis in the classification of this pragmatic principle. The data were obtained by an actions naming task composed of 17 brief videos, applied to 37 children aged between 2:0 and 3:0 and 43 children aged between 3:1 and 4:5. Two analyses were compared: (1) dichotomic - verbs classified as non conventional or conventional; and (2) continuous, scores between 1 and 5, obtained using a Likert scale. The results showed that the two kinds of analysis distinguish the age groups, although the continuous analysis presents advantages, revealing more details about the verbs lexical development.