Words said aloud are typically recalled more than words studied under other techniques. In certain circumstances, production does not lead to this memory advantage. We investigated the nature of this effect by varying the task during learning. Children aged five to six years were trained on novel words which required no action (Heard) compared to Verbal-Speech (production), Non-Verbal-Speech (stick out tongue), and Non-Verbal-Non-Speech (touch nose). Eye-tracking showed successful learning of novel words in all training conditions, but no differences between conditions. Both non-verbal tasks disrupted recall, demonstrating that encoding can be disrupted when children perform different types of concurrent actions.

When word learning is supported by instruction in experimental studies for adolescents, word knowledge outcomes tend to be collected from complex data structure, such as multiple aspects of word knowledge, multilevel reader data, multilevel item data, longitudinal design, and multiple groups. This study illustrates how generalized linear mixed models can be used to measure and explain word learning for data having such complexity. Results from this application provide deeper understanding of word knowledge than could be attained from simpler models and show that word knowledge is multidimensional and depends on word characteristics and instructional contexts.

An important question in literacy education is whether reading instruction should focus on whole words or subword constituents. We tested whether this question captures something general across writing systems by examining the functionalities of words and characters in learning Chinese. We introduce a character-word dual-focus instructional approach based on the Character-Word Dual Function model and test its predictions with American undergraduate students enrolled in a beginner-level Chinese course. One group learned new words through dual-focus instruction: characters for pronunciation and words for meaning. A second group followed typical word-focus instruction prevalent in classrooms, learning word-level pronunciation and meaning. Results indicated that while both approaches produced comparable levels of word pronunciation and meaning learning, the dual-focus instruction significantly enhanced character pronunciation and transfer to new word learning. The advantages of dual-focus instruction highlight the importance of learning the subword components through acquiring the systematic structure of the writing system in learning to read.

The study explored the origin of the age of acquisition (AoA) effect in second language (L2) using ERPs technique. We simulated L2 AoA by manipulating the order at which English pseudowords entered into training. Chinese-English bilinguals (mean age 22.04, range 18–28) learned English pseudowords matched with Chinese (L1) words, investigating the order of acquisition (OoA) effect of English pseudowords and its relationship with the matched L1 words’ AoA. OoA effects were observed in lexical decision, naming and semantic judgment tasks on N170, P200 and N400. Furthermore, OoA effects were modulated by L1 AoA in the semantic judgment task. These results suggested that OoA effects were independent at orthographic and phonological levels but modulated by L1 AoA at the semantic level. The interpretation of L2 AoA effects requires not only the integration of Semantic and Arbitrary Mapping Hypotheses, as well as consideration of the representation and activation characteristics of L2 words.

Six-month-olds infer object size based on pitch: they map high-pitched vowels onto smaller objects and low-pitched vowels onto larger objects (Peña et al., 2011). The ‘sound symbolism bootstrapping hypothesis’ (Imai & Kita, 2014) proposes that this may support understanding of word-meaning correspondences; by drawing on iconic pairings between linguistic cues and corresponding referents (e.g., higher pitch for smaller objects), infants develop understanding of word-referent associations. Here we analyse mother-child interactions, testing whether sound-symbolic pitch-size correspondences occur in infant-directed speech. 40 dyads engaged in (semi-)naturalistic interaction around picture books containing images of toys of varying sizes. We compare mothers’ pitch when referring to small versus large toys, analysing i) actual size (bigger vs. smaller toys); ii) relative toy size congruence (i.e., congruent vs. incongruent with real-world expectation); and iii) transparency of the test paradigm as regards its focus on size contrastiveness (non-transparent, moderately transparent, highly transparent) to observe the nuances of size sound symbolism in infant-directed speech.

Monomorphemic words have been found to influence category formation, as they encode one general category and thus activate it more than other related categories in the same lexical network. On the other hand, multimorphemic words can encode multiple categories from the same network by the multiple forms they combine. Superordinate categories are encoded by sub-lexical forms (e.g., affixes), while the entire words encode lower categories in the hierarchical structure. In the present study, we asked whether sub-lexical forms influence the learning of the meaning encoded by the entire word they underlie. We used Semitic-like words where sub-lexical forms (syllabic patterns) encode superordinate categories of manner-of-motion, and the entire words encode lower-level categories (moving characters). In our main experiment, a word-learning test showed that a shared syllabic pattern had a negative effect on the learning of the moving characters encoded by the entire word. This effect was revealed mainly in dimensions related to the superordinate category encoded by the pattern. The effect and its direction are beyond the expectations of enhanced category representations suggested in previous literature. We conclude that the effect of word-form is beyond the specific category they encode and can have different directions at different hierarchical levels.

Late talkers (LTs) exhibit delayed vocabulary development, which might stem from a lack of a typical word learning strategy to generalise object labels by shape, called the ‘shape bias’. We investigated whether LTs can acquire a shape bias and whether this accelerates vocabulary learning. Fourteen LTs were randomly allocated to either a shape training group (Mage = 2.76 years, 6 males), which was taught that objects similar in shape have the same name, or a control group (Mage = 2.61 years, 4 males), which was taught real words without any focus on object shape. After seven training sessions, children in the shape training group generalised trained labels by shape (d = 1.28), but not unfamiliar labels. Children in the control group extended all labels randomly. Training did not affect expressive vocabulary.

Second language (L2) learners need to acquire large vocabularies to approach native-like proficiency. Many controlled experiments have investigated the factors facilitating and hindering word learning; however, few studies have validated these findings in real-world learning scenarios. We use data from the language learning app Lingvist to explore how L2 word learning is affected by valence (positivity/negativity) and concreteness of target words and their linguistic contexts. We found that valence, but not concreteness, affects learning. Users learned positive and negative words better than neutral ones. Moreover, positive words are learned best in positive contexts and negative words in more negative contexts. Word and context valence effects are strongest on the learner’s second encounter with the target word and diminish across subsequent encounters. These findings provide support for theories of embodied cognition and the lexical quality hypothesis and point to the linguistic factors that make learning words, and by extension languages, faster.

Prosody includes the pitch, timing and loudness in speech, which can convey meaning and emotion. This study examines whether prosodic categories affect novel noun learning and whether the referent characteristic influence learning. Previous research showed that emotional prosody interfered with adults’ noun learning (West et al., 2017), but it had no effect on children (West et al., 2022). However, these researchers varied their method across ages, including animacy and complexity of the referent, and it is unclear if the results extend beyond the three emotional prosodies tested. Participants in the current set of studies heard novel words presented in five prosodic categories (within-subject) in order to learn the label for either animate or inanimate objects (between-subject). Study 1 compared inanimate objects and aliens, with better noun learning performance for inanimate objects. Study 2 compared inanimate objects with the same objects with faces added, but there was no difference in noun learning by object type. Both studies showed differences in noun learning by the prosodic category, with warning less accurate than naming. These results demonstrate how extralinguistic factors like prosody, attention and referent complexity influence noun learning.

Word-object and action-object learning in children aged 30 to 48 months appears to develop at a similar time scale and adheres to similar attentional constraints. However, children below 36 months show different patterns of learning word-object and action-object associations when this information is presented in a bimodal context (Eiteljoerge et al., 2019b). Here, we investigated 12- and 24-month-olds’ word-object and action-object learning when this information is presented in a unimodal context. Forty 12- and 24-month-olds were presented with two novel objects that were either first associated with a novel label (word learning task) and then later with a novel action (action learning task) or vice versa. In subsequent yoked test phases, children either heard one of the novel labels or saw a hand performing one of the actions presented with the two objects on screen while we measured their target looking. Generalized linear mixed models indicate that 12-month-olds learned action-object associations but not word-object associations and 24-month-olds learned neither word- nor action-object associations. These results extend previous findings (Eiteljoerge et al., 2019b) and, together, suggest that children appear to learn action-object associations early in development while struggling with learning word-object associations in certain contexts until 2 years of age.

During vocabulary instruction, it is important to teach words until their representations are robust enough to be retained. For adults, the number of training sessions a target item is successfully retrieved during training predicts the likelihood of post-training retention. To assess this relationship in children, we reanalyzed data from Gordon et al. (2021b, 2022). Four- to six-year-old children completed six training days with word form-object pairs and were tested one month later. Results indicate that the number of training sessions that a word form was retrieved was positively related to post-training retention. We discuss implications for vocabulary instruction and interventions.

Young children today are exposed to masks on a regular basis. However, there is limited empirical evidence on how masks may affect word learning. The study explored the effect of masks on infants’ abilities to fast-map and generalize new words. Seventy-two Chinese infants (43 males, Mage = 18.26 months) were taught two novel word-object pairs by a speaker with or without a mask. They then heard the words and had to visually identify the correct objects and also generalize words to a different speaker and objects from the same category. Eye-tracking results indicate that infants looked longer at the target regardless of whether a speaker wore a mask. They also looked longer at the speaker’s eyes than at the mouth only when words were taught through a mask. Thus, fast-mapping and generalization occur in both masked and not masked conditions as infants can flexibly access different visual cues during word-learning.

Adults differ in the ease with which they acquire lexical tones in a non-native language. Individual differences have been attributed to several factors, such as the role that pitch plays in a learner's L1 to signal lexical meaning (L1 tonal status), the shape of the tones to be acquired (tone types), as well as extralinguistic factors (such as musical experience and working memory). Here, we ask whether learners from a spectrum of L1 tonal statuses (Dutch, Swedish and Japanese, and Thai) differ in their tone word learning facility, whilst we simultaneously investigate the effects of tone type, and musical experience and working memory. Our findings suggest that above and beyond L1 tonal status, the strongest predictor of tone word learning was pre-lexical tone processing (measured by a tone categorization task), although the strength of the link between pre-lexical and lexical processing may be modulated by L1 tonal status.

How much information do language users need to differentiate potentially absolute synonyms into near-synonyms? How consistent must the information be? We present two simple experiments designed to investigate this. After exposure to two novel verbs, participants generalized them to positive or negative contexts. In Experiment 1, there was a tendency across conditions for the verbs to become differentiated by context, even following inconsistent, random, or neutral information about context during exposure. While a subset of participants matched input probabilities, a high proportion did not. As a consequence, the overall pattern was of growth in differentiation that did not closely track input distributions. Rather, there were two main patterns: When each verb had been presented consistently in a positive or negative context, participants overwhelmingly specialized both verbs in their output. When this was not the case, the verbs tended to become partially differentiated, with one becoming specialized and the other remaining less specialized. Experiment 2 replicated and expanded on Experiment 1 with the addition of a pragmatic judgment task and neutral contexts at test. Its results were consistent with Experiment 1 in supporting the conclusion that quality of input may be more important than quantity in the differentiation of synonyms.

The present study investigated the differential effects of pitched and unpitched musicianship on tone identification and word learning. We recruited 44 Cantonese-pitched musicians, unpitched musicians, and non-musicians. They completed a Thai tone identification task and seven sessions of Thai tone word learning. In the tone identification task, the pitched musicians outperformed the non-musicians but the unpitched musicians did not. In session 1 of the tone word learning task, the three groups showed similar accuracies. In session 7, the pitched musicians outperformed the non-musicians but the unpitched musicians did not. The results indicate that the musical advantage in tone identification and word learning hinges on pitched musicianship. From a theoretical perspective, these findings support the precision element of the OPERA hypothesis. Broadly, they reflect the need to consider the heterogeneity of musicianship when studying music-to-language transfer. Practically, the findings highlight the potential of pitched music training in enhancing tone word learning proficiency. Furthermore, the choice of musical instrument may matter to music-to-language transfer.

While there are well-known demonstrations that children can use distributional information to acquire multiple components of language, the underpinnings of these achievements are unclear. In the current paper, we investigate the potential pre-requisites for a distributional learning model that can explain how children learn their first words. We review existing literature and then present the results of a series of computational simulations with Vector Space Models, a type of distributional semantic model used in Computational Linguistics, which we evaluate against vocabulary acquisition data from children. We focus on nouns and verbs, and we find that: (i) a model with flexibility to adjust for the frequency of events provides a better fit to the human data, (ii) the influence of context words is very local, especially for nouns, and (iii) words that share more contexts with other words are harder to learn.

Meaning comes in different shapes and sizes. Content words like parrot and persimmon and perambulate convey some important – and very specific – kinds of meanings. But the kinds of meaning that syntactic structures encode are of a different sort. They are more general and abstract than those kinds of words, and they are linked to the underlying organization of language. The essential insight behind syntactic bootstrapping is that children can leverage the way that structural elements connect to abstract meanings to help them acquire the more specific kinds of meanings in the content words.

There is a current ‘theory crisis’ in language acquisition research, resulting from fragmentation both at the level of the approaches and the linguistic level studied. We identify a need for integrative approaches that go beyond these limitations, and propose to analyse the strengths and weaknesses of current theoretical approaches of language acquisition. In particular, we advocate that language learning simulations, if they integrate realistic input and multiple levels of language, have the potential to contribute significantly to our understanding of language acquisition. We then review recent results obtained through such language learning simulations. Finally, we propose some guidelines for the community to build better simulations.