The semantics and acquisition of number words: integrating linguistic and developmental perspectives

This article brings together two independent lines of research on numerally quantified expressions, e.g. two girls. One stems from work in linguistic theory and asks what truth conditional contributions such expressions make to the utterances in which they are used--in other words, what do numerals mean? The other comes from the study of language development and asks when and how children learn the meaning of such expressions. My goal is to show that when integrated, these two perspectives can both constrain and enrich each other in ways hitherto not considered. Specifically, work in linguistic theory suggests that in addition to their 'exactly n' interpretation, numerally quantified NPs such as two hoops can also receive an 'at least n' and an 'at most n' interpretation, e.g. you need to put two hoops on the pole to win (i.e. at least two hoops) and you can miss two shots and still win (i.e. at most two shots). I demonstrate here through the results of three sets of experiments that by the age of 5 children have implicit knowledge of the fact that expressions like two N can be interpreted as 'at least two N' and 'at most two N' while they do not yet know the meaning of corresponding expressions such as at least/most two N which convey these senses explicitly. I show that these results have important implications for theories of the semantics of numerals and that they raise new questions for developmental accounts of the number vocabulary.     

Accounting for children's orthographic learning while reading text: do children self-teach?

Share's "self-teaching" model proposes that readers acquire most knowledge about the orthographic structure of words incidentally while reading independently. In the current study, the self-teaching hypothesis was tested by simulating everyday reading through the use of real words, analyzing the effects of context, and considering the independent contributions of general cognitive ability, including rapid naming ability and prior orthographic knowledge. A total of 35 first graders read short story passages in English embedded with target words representative of words likely to be known orally but not orthographically. Words were manipulated for target word spelling and contextual support. According to the self-teaching model, words correctly decoded during reading should be correlated with subsequent orthographic learning. The results of this study confirmed this prediction. Self-teaching was evidenced through significantly higher proportions of correctly identified target words across context conditions. Regression analyses showed that individual differences were related to prior orthographic knowledge and predicted students' degree and quality of orthographic learning after controlling for general decoding ability.     

Constraints on children's color term acquisition

Kowalski and Zimiles (2006) and O'Hanlon and Roberson (2006) address an age-old question: Why do children find it difficult to learn color terms? Here these articles are reflected on, providing a focused examination of the issues central to this question. First, the criteria by which children are said to find color naming difficult are considered. Although the age of color term acquisition is decreasing, and color naming might not be more difficult than other abstract attributes, several stages of difficulty are identified. Second, it is argued that there are potentially multiple constraints (e.g., conceptual, attentional, and linguistic) for these multiple stages of difficulty with color term acquisition. Third, it is argued that the validity and reliability of techniques for identifying constraints need to be considered and that converging evidence for the constraints should be provided. Finally, a series of new questions that need to be asked to provide a well-rounded explanation of the difficulties children face when learning color terms is outlined.     

Idiomatic syntactic constructions and language learning

This article explores the influence of idiomatic syntactic constructions (i.e., constructions whose phrase structure rules violate the rules that underlie the construction of other kinds of sentences in the language) on the acquisition of phrase structure. In Experiment 1, participants were trained on an artificial language generated from hierarchical phrase structure rules. Some participants were given exposure to an idiomatic construction (IC) during training, whereas others were not. Under some circumstances, the presence of an idiomatic construction in the input aided learners in acquiring the phrase structure of the language. Experiment 2 provides a replication of the first experiment and extends the findings by showing that idiomatic constructions that strongly violate the predictive dependencies that define the phrase structure of the language do not aid learners in acquiring the structure of the language. Together, our data suggest that (a) idiomatic constructions aid learners in acquiring the phrase structure of a language by highlighting relevant structural elements in the language, and (b) such constructions are useful cues to learning to the extent that learners can keep their knowledge of the idiomatic construction separate from their knowledge of the rest of the language.     

Modeling the Development of Children's Use of Optional Infinitives in Dutch and English Using MOSAIC

In this study we use a computational model of language learning called model of syntax acquisition in children (MOSAIC) to investigate the extent to which the optional infinitive (OI) phenomenon in Dutch and English can be explained in terms of a resource-limited distributional analysis of Dutch and English child-directed speech. The results show that the same version of MOSAIC is able to simulate changes in the pattern of finiteness marking in 2 children learning Dutch and 2 children learning English as the average length of their utterances increases. These results suggest that it is possible to explain the key features of the OI phenomenon in both Dutch and English in terms of the interaction between an utterance-final bias in learning and the distributional characteristics of child-directed speech in the 2 languages. They also show how computational modeling techniques can be used to investigate the extent to which cross-linguistic similarities in the developmental data can be explained in terms of common processing constraints as opposed to innate knowledge of universal grammar.     

Information sources for noun learning

Why are some words easier to learn than others? And what enables the eventual learning of the more difficult words? These questions were addressed for nouns using a paradigm in which adults were exposed to naturalistic maternal input that was manipulated to simulate access to several different information sources, both alone and in combination: observation of the extralinguistic contexts in which the target word was used, the words that co‐occurred with the target word, and the target word's syntactic context. Words that were not accurately identified from observation alone were both abstract (e.g., music) and concrete (e.g., tail). Whether a noun could be learned from observation depended on whether it labeled a basic‐level object category (BLOC). However, the difference between BLOC labels and non‐BLOC labels was eliminated when observation was supplemented with linguistic context. Thus, although BLOC labels can be learned from observation alone, non‐BLOC labels require richer linguistic context. These findings support a model of vocabulary growth in which an important role is played by changes in the information to which learners have access.     

Uncovering the richness of the stimulus: structure dependence and indirect statistical evidence

The poverty of stimulus argument is one of the most controversial arguments in the study of language acquisition. Here we follow previous approaches challenging the assumption of impoverished primary linguistic data, focusing on the specific problem of auxiliary (AUX) fronting in complex polar interrogatives. We develop a series of corpus analyses of child-directed speech showing that there is indirect statistical information useful for correct auxiliary fronting in polar interrogatives and that such information is sufficient for distinguishing between grammatical and ungrammatical generalizations, even in the absence of direct evidence. We further show that there are simple learning devices, such as neural networks, capable of exploiting such statistical cues, producing a bias toward correct AUX questions when compared to their ungrammatical counterparts. The results suggest that the basic assumptions of the poverty of stimulus argument may need to be reappraised.     

Different types of environmental enrichment have discrepant effects on spatial memory and synaptophysin levels in female mice

Environmental enrichment paradigms that incorporate cognitive stimulation, exercise, and motor learning benefit memory and synaptic plasticity across the rodent lifespan. However, the contribution each individual element of the enriched environment makes to enhancing memory and synaptic plasticity has yet to be delineated. Therefore, the current study tested the effects of three of these elements on memory and synaptic protein levels. Young female C57BL/6 mice were given 3h of daily exposure to either rodent toys (cognitive stimulation) or running wheels (exercise), or daily acrobatic training for 6 weeks prior to and throughout behavioral testing. Controls were group housed, but did not receive enrichment. Spatial working and reference memory were tested in a water-escape motivated radial arm maze. Levels of the presynaptic protein synaptophysin were then measured in frontoparietal cortex, hippocampus, striatum, and cerebellum. Exercise, but not cognitive stimulation or acrobat training, improved spatial working memory relative to controls, despite the fact that both exercise and cognitive stimulation increased synaptophysin levels in the neocortex and hippocampus. These data suggest that exercise alone is sufficient to improve working memory, and that enrichment-induced increases in synaptophysin levels may not be sufficient to improve working memory in young females. Spatial reference memory was unaffected by enrichment. Acrobat training had no effect on memory or synaptophysin levels, suggesting a minimal contribution of motor learning to the mnemonic and neuronal benefits of enrichment. These results provide the first evidence that different elements of the enriched environment have markedly distinct effects on spatial memory and synaptic alterations.     

Sensory consciousness explained (better) in terms of ‘corporality’ and ‘alerting capacity’

How could neural processes be associated with phenomenal consciousness? We present a way to answer this question by taking the counterintuitive stance that the sensory feel of an experience is not a thing that happens to us, but a thing we do: a skill we exercise. By additionally noting that sensory systems possess two important, objectively measurable properties, corporality and alerting capacity, we are able to explain why sensory experience possesses a sensory feel, but thinking and other mental processes do not. We are additionally able to explain why different sensory feels differ in the way they do.     

The differential role of phonological and distributional cues in grammatical categorisation

Recognising the grammatical categories of words is a necessary skill for the acquisition of syntax and for on-line sentence processing. The syntactic and semantic context of the word contribute as cues for grammatical category assignment, but phonological cues, too, have been implicated as important sources of information. The value of phonological and distributional cues has not, with very few exceptions, been empirically assessed. This paper presents a series of analyses of phonological cues and distributional cues and their potential for distinguishing grammatical categories of words in corpus analyses. The corpus analyses indicated that phonological cues were more reliable for less frequent words, whereas distributional information was most valuable for high frequency words. We tested this prediction in an artificial language learning experiment, where the distributional and phonological cues of categories of nonsense words were varied. The results corroborated the corpus analyses. For high-frequency nonwords, distributional information was more useful, whereas for low-frequency words there was more reliance on phonological cues. The results indicate that phonological and distributional cues contribute differentially towards grammatical categorisation.