Some puzzling findings regarding the acquisition of verbs

On the whole, children acquire frequent words earlier than less frequent words. However, there are other factors at play, such as an early "noun bias" (relative to input frequency, toddlers learn nouns faster than verbs) and a "content-word bias" (content words are acquired disproportionately to function words). This paper follows up reports of a puzzling phenomenon within verb-learning, where "experiencer-object" emotion verbs (A frightened/angered/delighted B) are lower frequency but learned earlier than "experiencer-subject" emotion verbs (A feared/hated/loved B). In addition to the possibility that the aforementioned results are a fluke or due to some confound, prior work has suggested several possible explanations: experiencer-object ("frighten-type") verbs have higher type frequency, encode a causal agent as the sentential subject, and perhaps describe a more salient perspective on the described event. In three experiments, we cast doubt on all three possible explanations. The first experiment replicates and extends the prior findings regarding emotion verbs, ruling out several possible confounds and concerns. The second and third experiments investigate acquisition of chase/flee verbs and give/get verbs, which reveal surprising findings that are not explained by the aforementioned hypotheses. We conclude that these findings indicate a significant hole in our theories of language learning, and that the path forward likely requires a great deal more empirical investigation of the order of acquisition of verbs.

Testing the storage of prosody-induced phonetic detail via auditory lexical decision

This article reports the results of an auditory lexical decision task, testing the processing of phonetic detail of English noun/verb conversion pairs. The article builds on recent findings showing that the frequent occurrence in certain prosodic environments may lead to the storage of prosody-induced phonetic detail as part of the lexical representation. To investigate this question with noun/verb conversion pairs, ambicategorical stimuli were used that exhibit systematic occurrence differences with regard to prosodic environment, as indicated by either a strong verb-bias, e.g., talk (N/V) or a strong noun-bias, e.g., voice (N/V). The auditory lexical decision task tests whether acoustic properties reflecting either the typical or the atypical prosodic environment impact the processing of recordings of the stimuli. In doing so assumptions about the storage of prosody-induced phonetic detail are tested that distinguish competing model architectures. The results are most straightforwardly accounted for within an abstractionist architecture, in which the acoustic signal is mapped onto a representation that is based on the canonical pronunciation of the word.

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.

Identifying Areas of Overlap and Distinction in Early Lexical Profiles of Children with Autism Spectrum Disorder, Late Talkers, and Typical Talkers

This study compares the lexical composition of 118 children with autism spectrum disorder (ASD) aged 12 to 84 months with 4626 vocabulary-matched typically developing toddlers with and without language delay, aged 8 to 30 months. Children with ASD and late talkers showed a weaker noun bias. Additionally, differences were identified in the proportion of nouns and verbs, and in the semantic categories of animals, toys, household items and vehicles. Most differences appear to reflect the extent of the age differences between the groups. However, children with ASD produced fewer high-social verbs than typical talkers and late talkers, a difference that might be associated with ASD features. In sum, our findings identified areas of overlap and distinction across the developing lexical profiles.

Object and action naming in Russian- and German-speaking monolingual and bilingual children

The present study investigates the influence of word category on naming performance in two populations: bilingual and monolingual children. The question is whether and, if so, to what extent monolingual and bilingual children differ with respect to noun and verb naming and whether a noun bias exists in the lexical abilities of bilingual children. Picture naming of objects and actions by Russian–German bilingual children (aged 4–7 years) was compared to age-matched monolingual children. The results clearly demonstrate a naming deficit of bilingual children in comparison to monolingual children that increases with age. Noun learning is more fragile in bilingual contexts than is verb learning. In bilingual language acquisition, nouns do not predominate over verbs as much as is seen in monolingual German and Russian children. The results are discussed with respect to semantic-conceptual aspects and language-specific features of nouns and verbs, and the impact of input on the acquisition of these word categories.

Language-specific noun bias: evidence from bilingual children

ABSTRACTMost evidence concerning cross-linguistic variation in noun bias, the preponderance of nouns in early expressive lexicons (Gentner, 1982), has come from comparisons of monolingual children acquiring different languages. Such designs are susceptible to a number of potential confounders, including group differences in developmental level and sociodemographic characteristics. The aim of this study was to quantify noun bias in bilingual Mandarin–English toddlers whose expressive lexicons in each language contained 50–300 words. Parents of fifty children (1;10–2;6) reported separately on their English and Mandarin expressive lexicons. The mean percentage of Mandarin nouns (38%) was significantly lower than the percentage of English nouns (54%) and was robust to analyses of twelve potential covariates. Analyses of the most frequently reported words suggested that lexical reduplication could be considered as a potential influence on vocabulary composition in future studies. Results suggest that characteristics of the input significantly shape early lexicons.

Nouns and verbs in Chintang: children's usage and surrounding adult speech

ABSTRACTAnalyzing the development of the noun-to-verb ratio in a longitudinal corpus of four Chintang (Sino-Tibetan) children, we find that up to about age four, children have a significantly higher ratio than adults. Previous cross-linguistic research rules out an explanation of this in terms of a universal noun bias; instead, a likely cause is that Chintang verb morphology is polysynthetic and difficult to learn. This hypothesis is supported by the fact that the development of Chintang children's noun-to-verb ratio correlates significantly with the extent to which they show a similar flexibility with verbal morphology to that of the surrounding adults, as measured by morphological paradigm entropy. While this development levels off around age three, children continue to have a higher overall noun-to-verb ratio than adults. A likely explanation lies in the kinds of activities that children are engaged in and that are almost completely separate from adults' activities in this culture.