Why Word Learning is not Fast

Assessing vocabulary acquisition using a fast-mapping task in an Android application: A pilot study

PURPOSE

The aim of this study was to explore whether a fast mapping task embedded in an Android application (FastMApp) is a valid tool to assess referent selection abilities in Spanish-speaking children aged between 18 and 30 months. Traditional assessment tools for lexical development use static quantitative methods that assign children a final score to represent their overall vocabulary level. These methods fail to provide insights into the learning process, despite their potential relevance for clinical and educational purposes.

METHOD

Sixty Spanish-speaking children participated in this study. They completed the FastMApp (a 22-trials' fast mapping noun task including 4- and 5-item trials, with one unknown object), and their caregivers rated their child's vocabulary on a parent-rated vocabulary inventory measure.

RESULT

The data show a high percentage of responses to the task, indicating that the children were actively complied with the task. The scores for known labels are significantly higher compared to unknown labels, and the scores for 4-item trials are significantly higher compared to 5-item trials. We observed a strong and significant relationship between the scores in this task and the scores on the parent-rated vocabulary inventory measure.

CONCLUSION

The results suggest that FastMApp is suitable for assessing early vocabulary acquisition in Spanish-speaking children.

Contributions of Speaking, Listening, and Semantic Depth to Word Learning in Typical 3- and 4-Year-Olds

PURPOSE

This study examined learning via perception, learning via production, and semantic depth as contributors to word learning in preschool-aged children. There is broad evidence that semantic depth is an important contributor to word learning, especially when semantic cues are repeated and spaced out over time. Perceptual learning and production learning each support word learning sometimes, but not in all cases. The purpose of this study was to examine all three learning mechanisms within a single experimental paradigm.

METHOD

Thirty-six typically developing preschool children completed the experiment. They were familiarized with 16 novel words that were contextualized as alien names. These aliens came in four sets, each set comprising one base alien and three modified aliens marked by suffixes. Children completed four familiarizations: two in which they simply listened to the alien names (perceptual learning) and two where they repeated the alien names (production learning). Those conditions were crossed with a semantic depth manipulation (aliens with and without verbal semantic cues). Following each familiarization, referent identification and confrontation naming tasks were completed to assess learning.

RESULTS

Children were able to identify more alien referents following familiarizations with semantic depth. There were no significant effects of either perceptual learning or production learning.

CONCLUSIONS

This study confirms and expands on the benefits of semantic depth, but the results are unclear about the relative importance of perception and production to word learning. Nevertheless, the study suggests benefits to simultaneously studying multiple factors related to word learning.

Four Cases of Children With Phonological Impairment and Precocious Vocabulary: Making Sense of a Clinical Conundrum

PURPOSE

The purpose of this study was to describe the speech production, speech perception, vocabulary, and word learning abilities of lexically precocious 4-year-old children with phonological impairment, in an effort to better understand the underlying nature of phonological impairment in children.

METHOD

Using a case series approach, we identified four children with phonological impairment and precocious vocabulary abilities. Each child completed routine speech production and vocabulary assessments, as well as experimental speech perception and word learning tasks. The results from these tasks were then used to create profiles of each child's individual strengths and needs across the abilities assessed.

RESULTS

Although all four children presented with phonological impairment and lexically precocious receptive and expressive vocabulary, they differed in their specific speech errors. One child presented with phonological speech errors only, while the other three children presented with an interdental lisp alongside their phonological errors. Three children presented with average speech perception abilities, and one child presented with poorer speech perception. The same three children also showed some learning of novel nonwords 1 week post-initial exposure, while the other child showed no evidence of word learning 1 week post-initial exposure.

CONCLUSIONS

The clinical profiles of lexically precocious children with phonological impairment offered different insights into the nature of the problem. Although one child appeared to present with underspecified underlying representations of words, the other three children appeared to present with well-specified underlying representations. Of the three children with well-specified underlying representations, two appeared to have difficulty abstracting particular rules of the ambient phonological system. Further research is needed to improve our understanding of the underlying nature of phonological impairment.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.26307640.

Fostering retention of word learning: The number of training sessions children retrieve words positively relates to post-training retention

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.

Developmental change in English-learning children's interpretations of salient pitch contours in word learning

To efficiently recognize words, children learning an intonational language like English should avoid interpreting pitch-contour variation as signaling lexical contrast, despite the relevance of pitch at other levels of structure. Thus far, the developmental time-course with which English-learning children rule out pitch as a contrastive feature has been incompletely characterized. Prior studies have tested diverse lexical contrasts and have not tested beyond 30 months. To specify the developmental trajectory over a broader age range, we extended a prior study (Quam & Swingley, 2010), in which 30-month-olds and adults disregarded pitch changes, but attended to vowel changes, in newly learned words. Using the same phonological contrasts, we tested 3- to 5-year-olds, 24-month-olds, and 18-month-olds. The older two groups were tested using the language-guided-looking method. The oldest group attended to vowels but not pitch. Surprisingly, 24-month-olds ignored not just pitch but sometimes vowels as well-conflicting with prior findings of phonological constraint at 24 months. The youngest group was tested using the Switch habituation method, half with additional phonetic variability in training. Eighteen-month-olds learned both pitch-contrasted and vowel-contrasted words, whether or not additional variability was present. Thus, native-language phonological constraint was not evidenced prior to 30 months (Quam & Swingley, 2010). We contextualize our findings within other recent work in this area.

I remembered the chorm! Word learning abilities of children with and without phonological impairment

BACKGROUND

Children with phonological impairment present with pattern-based errors in their speech production. While some children have difficulties with speech perception and/or the establishment of robust underlying phonological representations, the nature of phonological impairment in children is still not well understood. Given that phonological and lexical development are closely linked, one way to better understand the nature of the problem in phonological impairment is to examine word learning abilities in children.

AIMS

To examine word learning and its relationship with speech perception, speech production and vocabulary knowledge in children aged 4-5 years. There were two variables of interest: speech production abilities ranging from phonological impairment to typical speech; and vocabulary abilities ranging from typical to above average ('lexically precocious').

METHODS & PROCEDURES

Participants were 49 Australian-English-speaking children aged 48-69 months. Children were each taught four novel non-words (out of a selection of eight) through stories, and word learning was assessed at 1 week post-initial exposure. Word learning was assessed using two measures: confrontation naming and story retell naming. Data were analysed by group using independent-samples t-tests and Mann-Whitney U-tests, and continuously using multiple linear regression.

OUTCOMES & RESULTS

There was no significant difference in word learning ability of children with and without phonological impairment, but regardless of speech group, children with above average vocabulary had significantly better word learning abilities than children with average vocabulary. In multiple linear regression, vocabulary was the only significant predictor of variance in word learning ability.

CONCLUSIONS & IMPLICATIONS

Children with phonological impairment can be lexically precocious and learn new words like their peers without phonological impairment. Contrary to expectations, vocabulary knowledge rather than expressive phonological ability explained variance in measures of word learning. These findings question an assumption that children with phonological impairment have underspecified phonological representations. They also highlight the heterogeneity among children with phonological impairment and the need to better understand the nature of their difficulty learning the phonological system of the ambient language.

WHAT THIS PAPER ADDS

What is already known on the subject There is limited research examining the word learning abilities of children with phonological impairment. Most previous research focuses on word properties such as phonotactic probability and neighbourhood density. Within the existing literature there are different reports and conclusions regarding the word learning abilities of children with phonological impairment and whether their word learning differs from that of children with typically developing speech. What this study adds to existing knowledge This study found that vocabulary was the strongest predictor of word learning across children with and without phonological impairment. There was no significant difference in word learning ability between children with and without phonological impairment. However, children with lexically precocious vocabulary abilities were significantly better at word learning than children with average vocabulary abilities. What are the potential or actual clinical implications of this work? Findings from this study support the importance of assessing and considering measures of word learning-including vocabulary-when working with children with phonological impairment. This study indicates that it is possible to use stories coupled with measures of confrontation naming and story retell to gain deeper insight into children's word learning abilities.

Children build their vocabularies in noisy environments: The necessity of a cross-disciplinary approach to understand word learning

Research within the language sciences has informed our understanding of how children build vocabulary knowledge especially during early childhood and the early school years. However, to date, our understanding of word learning in children is based primarily on research in quiet laboratory settings. The everyday environments that children inhabit such as schools, homes, and day cares are typically noisy. To better understand vocabulary development, we need to understand the effects of background noise on word learning. To gain this understanding, a cross-disciplinary approach between researchers in the language and hearing sciences in partnership with parents, educators, and clinicians is ideal. Through this approach we can identify characteristics of effective vocabulary instruction that take into account the background noise present in children's learning environments. Furthermore, we can identify characteristics of children who are likely to struggle with learning words in noisy environments. For example, differences in vocabulary knowledge, verbal working memory abilities, and attention skills will likely influence children's ability to learn words in the presence of background noise. These children require effective interventions to support their vocabulary development which subsequently should support their ability to process and learn language in noisy environments. Overall, this cross-disciplinary approach will inform theories of language development and inform educational and intervention practices designed to support children's vocabulary development. This article is categorized under: Psychology > Language Psychology > Learning Psychology > Theory and Methods.

Child word learning in song and speech

Listening to sung words rather than spoken words can facilitate word learning and memory in adults and school-aged children. To explore the development of this effect in young children, this study examined word learning (assessed as forming word-object associations) in 1- to 2-year olds and 3- to 4-year olds, and word long-term memory (LTM) in 4- to 5-year olds several days after the initial learning. In an intermodal preferential looking paradigm, children were taught a pair of words utilising adult-directed speech (ADS) and a pair of sung words. Word learning performance was better with sung words than with ADS words in 1- to 2-year olds (Experiments 1a and 1b), 3- to 4-year olds (Experiment 1a), and 4- to 5-year olds (Experiment 2b), revealing a benefit of song in word learning in all age ranges recruited. We also examined whether children successfully learned the words by comparing their performance against chance. The 1- to 2-year olds only learned sung words, but the 3- to 4-year olds learned both sung and ADS words, suggesting that the reliance on music features in word learning observed at ages 1-2 decreased with age. Furthermore, song facilitated the word mapping-recognition processes. Results on children's LTM performance showed that the 4- to 5-year olds' LTM performance did not differ between sung and ADS words. However, the 4- to 5-year olds reliably recalled sung words but not spoken words. The reliable LTM of sung words arose from hearing sung words during the initial learning rather than at test. Finally, the benefit of song on word learning and the reliable LTM of sung words observed at ages 3-5 cannot be explained as an attentional effect.

Word Learning as a Window to Memory and Rehabilitation Outcomes in Traumatic Brain Injury

PURPOSE

The purpose of this viewpoint is to advocate for increased study of word learning abilities and word learning interventions in traumatic brain injury (TBI).

METHOD

We describe the word learning process and the unique opportunities afforded by studying each component and stage. Building on discussions at the 2022 International Cognitive-Communication Disorders Conference, we describe how word learning may underlie a variety of functional outcomes after TBI, making it a promising target for rehabilitation. Finally, we discuss principles that may guide study in this critical area to advance outcomes after TBI for children and adults.

RESULTS

Word learning is a dynamic and iterative process taking place over time and in multiple stages. Thus, studying word learning affords the opportunity to parse the relative contributions of multiple memory systems to different phases and components of the process. However, single-timepoint designs are insufficient to capture the full word learning process, which occurs over time and across contexts. Word learning also presents an opportunity to assess the contributions of behavioral and lifestyle factors (e.g., sleep and exercise) to different memory phases. Understanding these interactions could drive clinical interventions aimed at improving memory through manipulable external behaviors.

CONCLUSIONS

Word learning is key to success in functional spheres across the life span. The importance of words to daily life remains after TBI, even as the memory systems that support word learning are disrupted. The empirical study of word learning and rehabilitation of word learning deficits in TBI presents a promising new direction in understanding the breadth of neurogenic cognitive-communication disorders and an opportunity to explore a potential driver of functional outcome and impactful rehabilitation target.

Examining the Relation Between Exercise and Word Learning in Preschool-Age Children

PURPOSE

There is evidence suggesting that aerobic exercise immediately after vocabulary training can improve word recall in school-age children. This work examined whether the previously identified word-learning benefits associated with exercise can be extended to preschoolers. Additionally, we evaluated whether the effects of physical activity on vocabulary learning may be influenced by existing language skills that the child possesses.

METHOD

Children ages 3-6 years completed the study (N = 42). Data were collected via a virtual testing session in which participants completed a word-learning task that included two experimental conditions (exercise and resting). In the resting measure, children were taught names of novel objects and then sat down and colored for 3 min before being tested on their ability to identify the trained words. The exercise condition was identical, except that participants engaged in 3 min of guided aerobic exercise before testing. Additionally, at the end of the visit, participants completed the Quick Interactive Language Screener (QUILS), which measured general language skills.

RESULTS

Accuracy of word recognition was significantly higher after the exercise condition compared to the resting condition. Furthermore, this pattern of results was not related to children's existing language skills, as measured by the QUILS.

CONCLUSIONS

This study is one of the first to closely examine the relation between physical activity and word-learning abilities in children as young as 3-6 years of age. Results align with previous findings stating that aerobic exercise can boost vocabulary learning and suggest that this is the case regardless of existing language skills.

Expressive vocabulary of school-age children with mild to moderately severe hearing loss

OBJECTIVES

The main goal of this study was to describe the expressive vocabulary of school-age children with mild to moderately severe hearing loss (CHL group) and to compare their performance with children with normal hearing (CNH group) of the same age. Another aim was to examine the interaction between nonword repetition and expressive vocabulary size. Furthermore, the interaction between results on vocabulary tests and background factors, such as the age of diagnosis, age of hearing aid fitting, and amount of hearing aid use, was explored.

METHOD

School-aged children with mild to moderately severe, permanent bilateral hearing loss and children with normal hearing were included in this cross-sectional study. The children participated in assessments of naming pictures, defining words, and repetition of nonwords and sentences. Results of the CHL group and the CNH group were compared. The analysis also included the degree of hearing loss, the age of diagnosis, amount of hearing aid use, and level of parental education.

RESULTS

The CHL group performed significantly below the CNH group on all measures: picture naming, defining words, nonword repetition, and repetition of sentences. The proportion of words pronounced with correct phonological structure when picture naming was more limited in the CHL group than in the CNH group. There was a significant positive correlation between the amount of hearing aid use and nonword repetition ability in the CHL group. Age of diagnosis and age of hearing aid fitting was not significantly correlated with the outcomes of the vocabulary assessments in this study.

CONCLUSION

Despite the technological advancement of hearing aids, the expressive vocabulary in school-aged children with mild to moderately severe, permanent bilateral, hearing impairment does not reach the same level as for children with normal hearing, although there is a variation in performance within the group. The variation in the CHL group was not uniquely impacted by either age, degree of hearing loss, or the age of diagnosis. The amount of hearing aid use seems to impact the perception of new words. More studies of expressive vocabulary are needed, because they capture a dimension of word learning that seems particularly sensitive to hearing loss and hearing aid use.

Multiple Mechanisms of Word Learning in Late-Talking Children: A Longitudinal Study

PURPOSE

The aim of this study was to identify variability in word-learning mechanisms used by late-talking children using a longitudinal study design, which may explain variability in late-talking children's outcomes.

METHOD

A cohort of typically developing children (n = 40) and children who were classified as late-talking children at age 2;0 (years;months; ≤ 10th percentile on expressive vocabulary, n = 21) were followed up at ages 3;0 and 3;6. We tested the cohort across tasks designed to isolate different mechanisms involved in word learning: encoding and producing spoken forms of words (using a nonword repetition task), identifying referents for words (using a fast mapping task), and learning associations between words and referents (using a cross-situational word-learning task).

RESULTS

Late-talking children had lower accuracy on nonword repetition than typically developing children, despite most of the sample reaching typical ranges for expressive vocabulary at age 3;6. There were no between-groups differences in fast mapping and retention accuracy; however, both were predicted by concurrent expressive vocabulary. Late-talking children performed less accurately than typically developing children on cross-situational word-learning retention trials, despite showing no between-groups differences during training trials. Combining performance across all three tasks predicted approximately 45% of the variance in vocabulary outcomes at the last time point.

CONCLUSIONS

Late-talking children continue to have deficits in phonological representation that impact their word-learning ability and expressive language abilities but do not show difficulties in fast mapping novel words. Late-talking children may also struggle to retain associative information about word-referent mappings. Late-talking children thus use some, but not all, word-learning mechanisms differently than typically developing children.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.20405856.

Word Learning by Preschool-Age Children: Differences in Encoding, Re-Encoding, and Consolidation Across Learners During Slow Mapping

PURPOSE

Children with typical development vary in how much experience they need to learn words. This could be due to differences in the amount of information encoded during periods of input, consolidated between periods of input, or both. Our primary purpose is to identify whether encoding, consolidation, or both, drive individual differences in the slow-mapping process.

METHOD

Four- to 6-year-old children (N = 43) were trained on nine form-referent pairs across consecutive days. Children's ability to name referents was assessed at the beginning and end of each session. Word learning was assessed 1 month after training to determine long-term retention.

RESULTS

Children with varying language knowledge and skills differed in their ability to encode words. Specifically, children varied in the number of words learned and the phonological precision of word forms at the end of the initial training session. Children demonstrated similarities in re-encoding in that they refined representations at a similar rate during subsequent sessions. Children did not differ in their ability to consolidate words between sessions, or in their ability to retain words over the 1-month delay.

CONCLUSIONS

The amount of experience children need to learn words is primarily driven by the amount of information encoded during the initial experience. When provided with high-quality instruction, children demonstrate a similar ability to consolidate and retain words. Critically, word learning instruction in educational settings must include repeated explicit instruction with the same words to support learning in children with typical development and varying language skills.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.19606150.

Word Learning by Preschool-Age Children With Developmental Language Disorder: Impaired Encoding and Robust Consolidation During Slow Mapping

Purpose Learning novel words, including the specific phonemes that make up word forms, is a struggle for many individuals with developmental language disorder (DLD). Building robust representations of words includes encoding during periods of input and consolidation between periods of input. The primary purpose of the current study is to determine differences between children with DLD and with typical development (TD) in the encoding and consolidation of word forms during the slow mapping process. Method Preschool-age children (DLD = 9, TD = 9) were trained on nine form-referent pairs across multiple consecutive training days. Children's ability to name referents at the end of training days indicated their ability to encode forms. Children's ability to name referents at the beginning of training days after a period of overnight sleep indicated their ability to consolidate forms. Word learning was assessed 1 month after training to determine long-term retention of forms. Results Throughout training, children with DLD produced fewer forms correctly and produced forms with less phonological precision than children with TD. Thus, children with DLD demonstrated impaired encoding. However, children with and without DLD demonstrated a similar ability to consolidate forms between training days and to retain forms across a 1-month delay. Conclusions Difficulties with word form learning are primarily driven by deficits in encoding for children with DLD. Clinicians and educators can support encoding by providing children with adequate exposures to target words via robust training that occurs across multiple sessions. Supplemental Material https://doi.org/10.23641/asha.16746454.

Optimising word learning in post-secondary students with Developmental Language Disorder: The roles of retrieval difficulty and retrieval success during training

PURPOSE

Learning words to the level that they can be readily retrieved and produced can be challenging. The primary aim of the current study is to determine how retrieval difficulty, based on the level of cuing provided, and retrieval success during training relate to the phonological precision with which words are produced after a delay.

METHOD

We performed additional analyses on data from McGregor, Gordon, Eden, Arbisi-Kelm, & Oleson, (Encoding deficits impede word learning and memory in adults with Developmental Language Disorders. Journal of Speech, Language, and Hearing Research, 60, 2891-2905) in which post-secondary students with Developmental Language Disorder (DLD, n = 23) and typical development (n = 25) were trained on words via free and cued recall practice and tested 24-h later.

RESULTS

Training via free recall led to more precise productions after the delay than training via cued recall for both groups. Additionally, the number of successful retrievals during training positively predicted retrieval after the delay. Furthermore, the precision of participants' last production and worst production of each word were the best predictors of production precision after the delay.

CONCLUSION

To optimally support encoding and delayed retrieval, students with and without DLD should utilise free recall practice. Additionally, words should be studied until they are successfully retrieved multiple times at a high level of phonological precision to support delayed retrieval.

Progressive Reduction of Iconic Gestures Contributes to School-Aged Children's Increased Word Production

The economic principle of communication, according to which successful communication can be reached by least effort, has been studied for verbal communication. With respect to nonverbal behavior, it implies that forms of iconic gestures change over the course of communication and become reduced in the sense of less pronounced. These changes and their effects on learning are currently unexplored in relevant literature. Addressing this research gap, we conducted a word learning study to test the effects of changing gestures on children's slow mapping. We applied a within-subject design and tested 51 children, aged 6.7 years (SD = 0.4), who learned unknown words from a story. The storyteller acted on the basis of two conditions: In one condition, in which half of the target words were presented, the story presentation was enhanced with progressively reduced iconic gestures (PRG); in the other condition, half of the target words were accompanied by fully executed iconic gestures (FEG). To ensure a reliable gesture presentation, children were exposed to a recorded person telling a story in both conditions. We tested the slow mapping effects on children's productive and receptive word knowledge three minutes as well as two to three days after being presented the story. The results suggest that children's production of the target words, but not their understanding thereof, was enhanced by PRG.

The Fast-Mapping Abilities of Adults With Developmental Language Disorder

Purpose The aim of the study was to determine the integrity of fast mapping among adults with developmental language disorder (DLD). Method Forty-eight adults with DLD or typical language development (TD) were presented with 24 novel words and photos of their unfamiliar referents from the semantic categories of mammal, bird, fruit, or insect in two conditions. In the fast-mapping condition, 12 of the 24 unfamiliar referents were presented, one at a time alongside a familiar referent (e.g., a dog) and a question (e.g., Is the tail of the torato up?). In the explicit-encoding condition, the other 12 unfamiliar referents were presented alone, one at a time, with a label (e.g., This is a spimer). Immediately after exposure (T1) and again after a 1-day interval (T2), memory for the word-to-exemplar link was measured with a three-alternative forced-choice test, requiring the participant to match a spoken word to one of three pictured referents from the training set. At T2, memory for semantic category information was measured with a four-alternative forced-choice test, requiring the participant to match a spoken word to one of four prototypical silhouettes representing each of the semantic categories. Results Performance on word-to-exemplar link recognition was stronger for words learned in the explicit-encoding than the fast-mapping condition and stronger for the TD group than the DLD group. Time was not a significant factor as both groups maintained posttraining levels of performance after a 1-day retention interval. Performance on semantic category recognition was stronger for words learned in the explicit-encoding than the fast-mapping condition and stronger for the TD group than the DLD group. The lower category recognition performance of the DLD group was related to their lower nonverbal IQ scores. Conclusion Contexts that allow for explicit encoding yield better learning of word-to-referent links than contexts that allow for fast mapping in both stronger and weaker learners. Adults with DLD have difficulty learning the link between words and referents, whether trained via fast mapping or explicit encoding and whether tested with exemplar or category referents. Retention is a relative strength for adults with DLD. Supplemental Material https://doi.org/10.23641/asha.12765551.

Symbolic Understanding and Word-Picture-Referent Mapping from iPads in Autism Spectrum Condition: The Roles of Iconicity and Engagement

We investigated symbolic understanding, word-picture-referent mapping, and engagement in children with autism spectrum condition (ASC) and ability-matched typically developing children. Participants viewed coloured pictorial symbols of a novel object (given a novel name) on an iPad in one of three conditions: static 2D images and either automatically or manually rotating images (providing a three-dimensional context). We found no significant difference in word-picture-referent mapping between groups and conditions, however, children who manually rotated the picture had greater on-screen looking time compared to other conditions. Greater visual attention related to more successful word-picture-referent mapping only for the children with ASC. Interactive iPad tasks may increase visual attention in both typical and atypical populations and greater visual attention may benefit word-picture-referent mapping in ASC.

Two-year-olds consolidate verb meanings during a nap

Successful word learning requires establishing an initial representation that is sufficiently robust to be retained in memory. Sleep has profound advantages for memory consolidation, but evidence concerning the effects of sleep in young children's word learning is slim and focuses almost exclusively on learning nouns. Verbs are representationally more complex and are often learned from non-concurrent linguistic and observational information (e.g., hearing "let's pour your milk" before the pouring event takes place). What remains unknown is whether initial representations built this way are robust enough to sustain a delay, and how these representations are affected by sleep. We presented two-year-olds with non-concurrent linguistic and observational information about novel verbs and immediately tested their knowledge of the verbs' meanings by evaluating their eye gaze as they looked at potential referents. Then, after a 4-hour delay during which half of the children napped and half remained awake, we retested them to see if they remembered the verbs' meanings. The results demonstrate differences in two-year-olds' representations of a novel verb before and after the delay; specifically, their verb representations withstood the 4-hour delay if they had napped, but decayed if they had remained awake.

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.

Visual and verbal semantic productions in children with ASD, DLD, and typical language

PURPOSE

Associations between visual and verbal input allow children to form, augment, and refine their semantic representations within their mental lexicons. However, children with autism spectrum disorder (ASD) and with developmental language disorder (DLD; also known as specific language impairment) process visual and verbal information differently than their typically developing peers, which may impact how they incorporate visual and verbal features into their semantic representations. The purpose of this exploratory study was to investigate how children with ASD and DLD use visually and verbally presented input to produce semantic representations of newly learned words.

METHOD

Semantic features produced by 36 school-aged children (12 with ASD, 12 with DLD, and 12 with typical language development) were extracted from previously collected novel word definitions and coded based on their initial presentation modality (either visual, verbal, or both in combination) during an extended novel word learning paradigm. These features were then analyzed to explore group differences in the use of visual and verbal input.

RESULTS

The children with ASD and DLD produced significantly more visually-presented semantic features than their typical peers in their novel word definitions. There were no differences between groups in the proportion of semantic features presented verbally or via both modalities in combination. Also, the children increased their production of semantic features presented via both modalities combined across the sessions; this same increase in production was not observed for the semantic features taught in either the visual or verbal modality alone.

CONCLUSION

Children with ASD and DLD benefit from visually presented semantic information, either in isolation or combined with verbal input, during tasks of word learning. Also, the reinforcement of combined visual-verbal input appears to enhance semantic learning over time.

The influence of evaluative right/wrong feedback on phonological and semantic processes in word learning

Feedback is typically incorporated in word learning paradigms, in both research studies and commercial language learning apps. While the common-sense view is that feedback is helpful during learning, relatively little empirical evidence exists about the role of feedback in spoken vocabulary learning. Some work has suggested that long-term word learning is not enhanced by the presence of feedback, and that words are best learned implicitly. It is also plausible that feedback might have differential effects when learners focus on learning semantic facts, or when they focus on learning a new phonological sequence of sounds. In this study, we assess how providing evaluative (right/wrong) feedback on a spoken response influences two different components of vocabulary learning, the learning of a new phonological form, and the learning of a semantic property of the phonological form. We find that receiving evaluative feedback improves retention of phonological forms, but not of semantic facts.

Mine, Mine, Mine: Self-Reference and Children's Retention of Novel Words

Adults demonstrate enhanced memory for words encoded as belonging to themselves compared to those belonging to another. Known as the self-reference effect, there is evidence for the effect in children as young as three. Toddlers are efficient in linking novel words to novel objects, but have difficulties retaining multiple word-object associations. The aim here was to investigate the self-reference ownership paradigm on 3-year-old children's retention of novel words. Following exposure to each of four novel word-object pairings, children were told that objects either belonged to them or another character. Children demonstrated significantly higher immediate retention of self-referenced compared to other-referenced items. Retention was also tested 4 h later and the following morning. Retention for self- and other-referenced words was significantly higher than chance at both delayed time points, but the difference between the self- and other-referenced words was no longer significant. The findings suggest that when it comes to toddlers' retention of multiple novel words there is an initial memory enhancing effect for self- compared to other-referenced items, but the difference diminishes over time. Children's looking times during the self-reference presentations were positively associated with retention of self-referenced words 4 h later. Looking times during the other-reference presentations were positively associated with proportional looking at other-referenced items during immediate retention testing. The findings have implications for children's memory for novel words and future studies could test children's explicit memories for the ownership manipulation itself and whether the effect is superior to other forms of memory supports such as ostensive naming.

Semantic richness and word learning in children with autism spectrum disorder

Semantically rich learning contexts facilitate semantic, phonological, and articulatory aspects of word learning in children with typical development (TD). However, because children with autism spectrum disorder (ASD) show differences at each of these processing levels, it is unclear whether they will benefit from semantic cues in the same manner as their typical peers. The goal of this study was to track how the inclusion of rich, sparse, or no semantic cues influences semantic, phonological, and articulatory aspects of word learning in children with ASD and TD over time. Twenty-four school-aged children (12 in each group), matched on expressive vocabulary, participated in an extended word learning paradigm. Performance on five measures of learning (referent identification, confrontation naming, defining, phonetic accuracy, and speech motor stability) were tracked across three sessions approximately one week apart to assess the influence of semantic richness on extended learning. Results indicate that children with ASD benefit from semantically rich learning contexts similarly to their peers with TD; however, one key difference between the two groups emerged - the children with ASD showed heightened shifts in speech motor stability. These findings offer insights into common learning mechanisms in children with ASD and TD, as well as pointing to a potentially distinct speech motor learning trajectory in children with ASD, providing a window into the emergence of stereotypic vocalizations in these children.

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.

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.

Encoding Deficits Impede Word Learning and Memory in Adults With Developmental Language Disorders

Purpose

The aim of this study was to determine whether the word-learning challenges associated with developmental language disorder (DLD) result from encoding or retention deficits.

Method

In Study 1, 59 postsecondary students with DLD and 60 with normal development (ND) took the California Verbal Learning Test-Second Edition, Adult Version (Delis, Kramer, Kaplan, & Ober, 2000). In Study 2, 23 postsecondary students with DLD and 24 with ND attempted to learn 9 novel words in each of 3 training conditions: uncued test, cued test, and no test (passive study). Retention was measured 1 day and 1 week later.

Results

By the end of training, students with DLD had encoded fewer familiar words (Study 1) and fewer novel words (Study 2) than their ND peers as evinced by word recall. They also demonstrated poorer encoding as evinced by slower growth in recall from Trials 1 to 2 (Studies 1 and 2), less semantic clustering of recalled words, and poorer recognition (Study 1). The DLD and ND groups were similar in the relative amount of information they could recall after retention periods of 5 and 20 min (Study 1). After a 1-day retention period, the DLD group recalled less information that had been encoded via passive study, but they performed as well as their ND peers when recalling information that had been encoded via tests (Study 2). Compared to passive study, encoding via tests also resulted in more robust lexical engagement after a 1-week retention for DLD and ND groups.

Conclusions

Encoding, not retention, is the problematic stage of word learning for adults with DLD. Self-testing with feedback lessens the deficit.

Supplemental Materials

https://doi.org/10.23641/asha.5435200.

"I use it when I see it": The role of development and experience in Deaf and hearing children's understanding of iconic gesture

Iconicity is prevalent in gesture and in sign languages, yet the degree to which children recognize and leverage iconicity for early language learning is unclear. In Experiment 1 of the current study, we presented sign-naïve 3-, 4- and 5-year-olds (n=87) with iconic shape gestures and no additional scaffolding to ask whether children can spontaneously map iconic gestures to their referents. Four- and five-year-olds, but not three-year-olds, recognized the referents of iconic shape gestures above chance. Experiment 2 asked whether preschoolers (n=93) show an advantage in fast-mapping iconic gestures compared to arbitrary ones. We found that iconicity played a significant role in supporting 4- and 5-year-olds' ability to learn new gestures presented in an explicit pedagogical context, and a lesser role in 3-year-olds' learning. Using similar tasks in Experiment 3, we found that Deaf preschoolers (n=41) exposed to American Sign Language showed a similar pattern of recognition and learning but starting at an earlier age, suggesting that learning a language with rich iconicity may lead to earlier use of iconicity. These results suggest that sensitivity to iconicity is shaped by experience, and while not fundamental to the earliest stages of language development, is a useful tool once children unlock these form-meaning relationships.

Words to Sleep On: Naps Facilitate Verb Generalization in Habitually and Nonhabitually Napping Preschoolers

A nap soon after encoding leads to better learning in infancy. However, whether napping plays the same role in preschoolers' learning is unclear. In Experiment 1 (N = 39), 3-year-old habitual and nonhabitual nappers learned novel verbs before a nap or a period of wakefulness and received a generalization test examining word extension to novel actors after 24 hr. Only habitual and nonhabitual nappers who napped after learning generalized 24 hr later. In Experiment 2 (N = 40), children learned the same verbs but were tested within 2-3 min of training. Here, habitual and nonhabitual nappers retained the mappings but did not generalize. The results suggest that naps consolidate weak learning that habitual and nonhabitual nappers would otherwise forget over periods of wakefulness.

The Effect of Number and Presentation Order of High-Constraint Sentences on Second Language Word Learning

This paper presents the results of an experiment that investigated the effects of number and presentation order of high-constraint sentences on semantic processing of unknown second language (L2) words (pseudowords) through reading. All participants were Chinese native speakers who learned English as a foreign language. In the experiment, sentence constraint and order of different constraint sentences were manipulated in English sentences, as well as L2 proficiency level of participants. We found that the number of high-constraint sentences was supportive for L2 word learning except in the condition in which high-constraint exposure was presented first. Moreover, when the number of high-constraint sentences was the same, learning was significantly better when the first exposure was a high-constraint exposure. And no proficiency level effects were found. Our results provided direct evidence that L2 word learning benefited from high quality language input and first presentations of high quality language input.

Preschool Children's Memory for Word Forms Remains Stable Over Several Days, but Gradually Decreases after 6 Months

Research on word learning has focused on children's ability to identify a target object when given the word form after a minimal number of exposures to novel word-object pairings. However, relatively little research has focused on children's ability to retrieve the word form when given the target object. The exceptions involve asking children to recall and produce forms, and children typically perform near floor on these measures. In the current study, 3- to 5-year-old children were administered a novel test of word form that allowed for recognition memory and manual responses. Specifically, when asked to label a previously trained object, children were given three forms to choose from: the target, a minimally different form, and a maximally different form. Children demonstrated memory for word forms at three post-training delays: 10 mins (short-term), 2-3 days (long-term), and 6 months to 1 year (very long-term). However, children performed worse at the very long-term delay than the other time points, and the length of the very long-term delay was negatively related to performance. When in error, children were no more likely to select the minimally different form than the maximally different form at all time points. Overall, these results suggest that children remember word forms that are linked to objects over extended post-training intervals, but that their memory for the forms gradually decreases over time without further exposures. Furthermore, memory traces for word forms do not become less phonologically specific over time; rather children either identify the correct form, or they perform at chance.

The Effect of Sleep on Children's Word Retention and Generalization

In the first few years of life children spend a good proportion of time sleeping as well as acquiring the meanings of hundreds of words. There is now ample evidence of the effects of sleep on memory in adults and the number of studies demonstrating the effects of napping and nocturnal sleep in children is also mounting. In particular, sleep appears to benefit children's memory for recently-encountered novel words. The effect of sleep on children's generalization of novel words across multiple items, however, is less clear. Given that sleep is polyphasic in the early years, made up of multiple episodes, and children's word learning is gradual and strengthened slowly over time, it is highly plausible that sleep is a strong candidate in supporting children's memory for novel words. Importantly, it appears that when children sleep shortly after exposure to novel word-object pairs retention is better than if sleep is delayed, suggesting that napping plays a vital role in long-term word retention for young children. Word learning is a complex, challenging, and important part of development, thus the role that sleep plays in children's retention of novel words is worthy of attention. As such, ensuring children get sufficient good quality sleep and regular opportunities to nap may be critical for language acquisition.

Can 28-Month-Old Children Learn Spatial Prepositions Robustly from Pictures? Yes, When Narrative Input Is Provided

The learning of spatial prepositions is assumed to be based on experience in space. In a slow mapping study, we investigated whether 31 German 28-month-old children could robustly learn the German spatial prepositions hinter [behind] and neben [next to] from pictures, and whether a narrative input can compensate for a lack of immediate experience in space. One group of children received pictures with a narrative input as a training to understand spatial prepositions. In two further groups, we controlled (a) for the narrative input by providing unconnected speech during the training and (b) for the learning material by training the children on toys rather than pictures. We assessed children's understanding of spatial prepositions at three different time points: pretest, immediate test, and delayed posttest. Results showed improved word retention in children from the narrative but not the control group receiving unconnected speech. Neither of the trained groups succeeded in generalization to novel referents. Finally, all groups were instructed to deal with untrained material in the test to investigate the robustness of learning across tasks. None of the groups succeeded in this task transfer.

Learning verb syntax via listening: New evidence from 22-month-olds

Children recruit verb syntax to guide verb interpretation. We asked whether 22-month-olds spontaneously encode information about a particular novel verb's syntactic properties through listening to sentences, retain this information in long-term memory over a filled delay, and retrieve it to guide interpretation upon hearing the same novel verb again. Children watched dialogues in which interlocutors discussed unseen events using a novel verb in transitive (e.g., "Anna blicked the baby") or intransitive sentences ("Anna blicked"). Children later heard the verb in isolation ("Find blicking!") while viewing a two-participant causal action and a one-participant action event. Children who had heard transitive dialogues looked longer at the two-participant event than did those who heard intransitive dialogues. This effect disappeared if children heard a different novel verb at test ("Find kradding!"). These findings implicate a role for distributional learning in early verb learning: Syntactic-combinatorial information about otherwise unknown words may pervade the toddler's lexicon, guiding later word interpretation.

What a difference a day makes: change in memory for newly learned word forms over 24 hours

PURPOSE

This study explored the role of time and retrieval experience in the consolidation of word forms.

METHOD

Participants were 106 adults trained on 16 novel word-referent pairs, then tested immediately and 24 hr later for recognition and recall of word forms. In the interim, tests were repeated 2 hr or 12 hr after training, or not at all, thus varying the amount and timing of retrieval experience.

RESULTS

Recognition accuracy was stable and speed improved over the 24-hr period. But these manifestations of consolidation did not depend on interim retrieval experience; in fact, the 2-hr interim test interfered with improvements in speed. In contrast, the number of word forms recalled increased only with interim retrieval experiences, and the 12-hr interim test was more advantageous to recall than the 2-hr test.

CONCLUSIONS

After a word form is encoded, it can become stronger with time. Retrieval experience can also strengthen the trace, but, if retrieval occurs when the memory is still labile, it can be disruptive. This complex interplay between retrieval experience and time holds implications for measuring learning outcomes and for scheduling practice in classrooms and clinics.

Effects of speech practice on fast mapping in monolingual and bilingual speakers

PURPOSE

This study examines the effects of the levels of speech practice on fast mapping in monolingual and bilingual speakers.

METHOD

Participants were 30 English-speaking monolingual and 30 Spanish-English bilingual young adults. Each participant was randomly assigned to 1 of 3 practice conditions prior to the fast-mapping task: (a) intensive speech practice, (b) moderate speech practice, or (c) no practice. In a fast-mapping experiment, each participant was briefly exposed to novel objects and their corresponding novel words. Participants' knowledge of the target novel words was assessed immediately after the exposures.

RESULTS

There were significant effects of speech practice on fast mapping for both monolingual and bilingual adults. It is important to note that participants' language experience also played a role in their fast-mapping performance.

CONCLUSION

The findings suggest that speech practice, interacting with language experience, facilitates the processes for fast mapping.

A spatially supported forced-choice recognition test reveals children's long-term memory for newly learned word forms

Children's memories for the link between a newly trained word and its referent have been the focus of extensive past research. However, memory for the word form itself is rarely assessed among preschool-age children. When it is, children are typically asked to verbally recall the forms, and they generally perform at floor on such tests. To better measure children's memory for word forms, we aimed to design a more sensitive test that required recognition rather than recall, provided spatial cues to off-set the phonological memory demands of the test, and allowed pointing rather than verbal responses. We taught 12 novel word-referent pairs via ostensive naming to sixteen 4- to 6-year-olds and measured their memory for the word forms after a week-long retention interval using the new spatially supported form recognition test. We also measured their memory for the word-referent links and the generalization of the links to untrained referents with commonly used recognition tests. Children demonstrated memory for word forms at above chance levels; however, their memory for forms was poorer than their memory for trained or generalized word-referent links. When in error, children were no more likely to select a foil that was a close neighbor to the target form than a maximally different foil. Additionally, they more often selected correct forms that were among the first six than the last six to be trained. Overall, these findings suggest that children are able to remember word forms after a limited number of ostensive exposures and a long-term delay. However, word forms remain more difficult to learn than word-referent links and there is an upper limit on the number of forms that can be learned within a given period of time.

The role of partial knowledge in statistical word learning

A critical question about the nature of human learning is whether it is an all-or-none or a gradual, accumulative process. Associative and statistical theories of word learning rely critically on the later assumption: that the process of learning a word's meaning unfolds over time. That is, learning the correct referent for a word involves the accumulation of partial knowledge across multiple instances. Some theories also make an even stronger claim: partial knowledge of one word-object mapping can speed up the acquisition of other word-object mappings. We present three experiments that test and verify these claims by exposing learners to two consecutive blocks of cross-situational learning, in which half of the words and objects in the second block were those that participants failed to learn in Block 1. In line with an accumulative account, Re-exposure to these mis-mapped items accelerated the acquisition of both previously experienced mappings and wholly new word-object mappings. But how does partial knowledge of some words speed the acquisition of others? We consider two hypotheses. First, partial knowledge of a word could reduce the amount of information required for it to reach threshold, and the supra-threshold mapping could subsequently aid in the acquisition of new mappings. Alternatively, partial knowledge of a word's meaning could be useful for disambiguating the meanings of other words even before the threshold of learning is reached. We construct and compare computational models embodying each of these hypotheses and show that the latter provides a better explanation of the empirical data.

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.

Word learning processes in children with cochlear implants

PURPOSE

To determine whether 3 aspects of the word learning process-fast mapping, retention, and extension-are problematic for children with cochlear implants (CIs).

METHOD

The authors compared responses of 24 children with CIs, 24 age-matched hearing children, and 23 vocabulary-matched hearing children to a novel object noun training episode. Comprehension and production were measured immediately following training (fast mapping) as well as 1 day later (retention). Extension was measured in terms of the ability of the participants to identify new (untrained) exemplars.

RESULTS

Compared with their hearing age-mates, children with CIs performed marginally more poorly on fast mapping as measured by the comprehension probe and more poorly on retention as measured by comprehension and production probes. The age-mates improved over the retention interval, but the children with CIs did not. Most of the children with CIs performed similarly to their age-mates on extension, but 2 children underextended, and 5 children failed to understand the task. Compared with younger vocabulary-matched peers, children with CIs did not differ at fast mapping, retention, or extension.

CONCLUSIONS

Children with CIs demonstrated deficits in word learning, with retention being especially problematic. Their learning did not differ from that of younger children with similarly sized vocabularies.

Remembering new words: integrating early memory development into word learning

In order to successfully acquire a new word, young children must learn the correct associations between labels and their referents. For decades, word-learning researchers have explored how young children are able to form these associations. However, in addition to learning label-referent mappings, children must also remember them. Despite the importance of memory processes in forming a stable lexicon, there has been little integration of early memory research into the study of early word learning. After discussing what we know about how young children remember words over time, this paper reviews the infant memory development literature as it relates to early word learning, focusing on changes in retention duration, encoding, consolidation, and retrieval across the first 2 years of life. A third section applies this review to word learning and presents future directions, arguing that the integration of memory processes into the study of word learning will provide researchers with novel, useful insights into how young children acquire new words.