We report an experiment designed to identify how contextual information can influence children's performance on an experimental task involving temporal terms. Grain (1982) reported improved performance on a comprehension task when subjects were provided with contextual information, and he suggested that the improvement was due to satisfaction of presuppositions. However, this contextual information might have served to simplify task demands by providing prior information concerning an important aspect of the task. The present study distinguishes these factors by incorporating contextual information into the subordinate clause of the test sentences in a comprehension experiment (to satisfy presupposions) or into the main clause (to provide comparable prior information without satisfying presuppositions). We conclude that contextual information results in a significant improvement only when such information can be used to satisfy presuppositions.

The distinctions between the mental terms, know, think and sure was examined in an experiment with 60 children between three and six years of age. The children were required to find an object hidden in one of two places. Their only clues were two statements involving contrasting mental terms, with each statement referring to one of the possible hiding places. Results showed a significant improvement with age for the know-think and sure-think contrasts, with think treated as a less reliable index of location than both know and sure by four to five years of age. No change with age was found for know-sure contrast. It is concluded that by four to five years of age, children recognize the function of mental terms to express degrees of certainty, and that this understanding is probably not based on the factive properties of the terms.

Children understand gesture+speech combinations in which a deictic gesture adds new information to the accompanying speech by age 1;6 (Morford & Goldin-Meadow, 1992; ‘push’+point at ball). This study explores how early children understand gesture+speech combinations in which an iconic gesture conveys additional information not found in the accompanying speech (e.g., ‘read’+BOOK gesture). Our analysis of two- to four-year-old children's responses in a gesture+speech comprehension task showed that children grasp the meaning of iconic co-speech gestures by age three and continue to improve their understanding with age. Overall, our study highlights the important role gesture plays in language comprehension as children learn to unpack increasingly complex communications addressed to them at the early ages.

Some theories of Developmental Language Disorder (DLD) explain the linguistic deficits observed in terms of limitations in non-linguistic cognitive systems such as working memory. The goal of this research is to clarify the relationship between working memory and the processing of complex sentences by exploring the performance of 28 French-speaking children with DLD aged five to fourteen years and 48 typically developing children of the same age in memory and linguistic tasks. We identified predictive relationships between working memory and the comprehension and repetition of complex sentences in both groups. As for syntactic measures in spontaneous language, it is the complex spans that explain the major part of the variance in the control children. In children with DLD, however, simple spans are predictive of these syntactic measures. Our results thus reveal a robust relationship between working memory and syntactic complexity, with clinical implications for the treatment of children with DLD.

The present study examined early vocabulary development in fifty-nine French monolingual and fifty French–English bilingual infants (1;4–1;6). Vocabulary comprehension was assessed using both parental report (MacArthur-Bates Communicative Development Inventory; CDI) and the Computerized Comprehension Task (CCT). When assessing receptive vocabulary development using parental report, the bilinguals knew more words in their L1 versus their L2. However, young bilinguals were as accurate in L1 as they were in L2 on the CCT, and exhibited no difference in speed of word comprehension across languages. The proportion of translation equivalents in comprehension varied widely within this sample of young bilinguals and was linked to both measures of vocabulary size but not to speed of word retrieval or exposure to L2. Interestingly, the monolinguals outperformed the bilinguals with respect to accuracy but not reaction time in their L1 and L2. These results highlight the importance of using multiple measures to assess early vocabulary development.

Previous studies of children's knowledge of grammatical well-formedness have typically involved eliciting acceptability judgements from children. In the present study, children were expected to employ their tacit knowledge of the rules of grammar to correct sentences containing grammatical rule violations. Two groups of children (mean ages of 5;5 and 6;4) were presented with ungrammatical sentences resulting from either word-order changes or morpheme deletions. The results indicated that both groups of children performed well when presented with ungrammatical sentences containing morpheme deletions; but the performance of both groups was lower for the word-order violations, with the difference between the two types being greater for the 5-year-olds. It is argued that these results reflect differences in the extent to which the two types of rule violations rendered the original sentences meaningless.

Language exerts a powerful influence on our concepts. We review evidence documenting the developmental origins of a precocious link between language and object categories in very young infants. This collection of studies documents a cascading process in which early links between language and cognition provide the foundation for later, more precise ones. We propose that, early in life, language promotes categorization at least in part through its status as a social, communicative signal. But over the first year, infants home in on the referential power of language and, by their second year, begin teasing apart distinct kinds of names (e.g. nouns, adjectives) and their relation to distinct kinds of concepts (e.g. object categories, properties). To complement this proposal, we also relate this evidence to several alternative accounts of language's effect on categorization, appealing to similarity (‘labels-as-features’), familiarity (‘auditory overshadowing’), and communicative biases (‘natural pedagogy’).

This study compared the effects of three types of adult feedback (acceptance, correction with joint labelling, and correction with explanation) on young children's inappropriate word usage. Four children were visited in their homes twice a week, from the time they were between 1;1 and 1;3 until they were approximately 1;7. Differential feedback was applied by the experimenter whenever the children extended a term to referents that were inappropriate, but similar to appropriate ones. Comprehension and production probes were administered prior to, during, and following the feedback trials to assess changes in word usage over time. Results indicated that the three types of feedback varied in their relative effectiveness in facilitating a positive change in word usage. Correction with explanation was more effective than correction with joint labelling, which in turn was more effective than simple acceptance.

The count/mass distinction represents a categorical differentiation of nouns into count nouns which can be individuated when quantified (e.g. a car, several tables) and mass nouns which may not (cf. *a water, *several sands). The emergence of this distinction was examined in the longitudinal speech data of two children. In the first analysis, use of count nouns and mass nouns was compared in noun phrase contexts that require count nouns (e.g. a X, another X). It was found that from the earliest samples children used more count nouns in these contexts, hence showing a distributional distinction of noun types. This result suggests very rapid acquisition of count/mass subcategories. A series of further analyses assessed the possibility that early differentiation of count and mass nouns may be due to rote learning. No evidence was found for this proposal. A final analysis examined the development of a rule that requires that singular count nouns must be modified by a determiner. Acquisition here was found to be more protracted in nature since determiners are not used consistently in ‘telegraphic’ speech. Problems concerning the learnability of the obligatory determiner rule are discussed along with some speculations concerning the role of semantics in the acquisition of the count/mass distinction.

Subjects aged 3;6–9;0 were asked to judge sentences in which much and many modified prototypical and non-prototypical mass and count nouns, and to correct those sentences judged to be deviant. The experimental results indicate that children do not approach the co-occurrence conditions of much and many with various nouns from a semantic point of view, but rather from a morphosyntactic or surface-distributional one. Children learn the proper form that the noun must take in these constructions before they learn the proper choice of quantifier. In addition, they reserve many for use with plural count nouns long before they learn that much is restricted in direct noun modification to use with singular mass nouns.

The purpose of this research was to investigate the potential interaction of conceptual representations and linguistic systems in the process of language acquisition. Language–thought interactions were studied in 80 American, 48 Finnish and 48 Polish preschool children. The research focused on the conceptual and linguistic development of space and time. The spatial and temporal conceptual tasks were designed to measure the transition from experiential to inferential knowledge of space/time representations. In the linguistic domain, comprehension and production tests were used to evaluate the children's capacity to understand mono- and bi-referential location in space and time, where mono-referential location involves a single referent object/event with intrinsic properties (e.g. in/on or past/non-past), and bi-referential location requires two or more referent objects/events and relative perspective (e.g. deictic front/back or before/after). The conceptual and linguistic tests revealed significant changes during the period from two to five years of age, and measures of conceptual development were correlated with measures of linguistic development. As spatial and temporal representations became more structured, children were able to move from mono- to bi-referential location. In a comprehension test, we discovered an interaction of language by dimension. Finnish children found spatial distinctions relatively easy and Polish children found temporal distinctions relatively easy. This interaction was expected on the basis of the relative complexity of the morpho-syntactic coding in the spatial and temporal systems of the two languages. However, the argument relating the timing of acquisition to the transparency versus opacity of the linguistic systems was not supported by the English language comparison. Finally, the Finnish children were relatively better able to accomplish the spatial conceptual tasks as compared to the Polish children. This finding is consistent with a developmental concept of linguistic relativity. In general, the research indicates that spatial and temporal linguistic systems and representational knowledge interact during development with the influence occurring in both directions.

The first word-formation devices children should learn, we proposed, are the most productive ones, that is, those that have the fewest structural constraints on their use and that appear most frequently in the formation of new words. Four- and five-year-old children who were asked to recall novel words with English agentive suffixes recalled the most productive suffix (-er) well and its less productive companions (-ist and -ian) very poorly. Other children who were asked to recall as agentive suffixes the non-agentive -ly (about equal in frequency to -er) together with -ist and -ian, did poorly on all three. They also substituted agentive suffixes (including -er) for the non-agentive -ly, with greater reliance on more productive forms. These data, together with previous observations, support the hypothesis that productivity affects the order in which children master word-formation devices.

Experiment I required first, third, and sixth graders to identify the actor or experiencer from active and passive sentences with actional and three subclasses of experiential verbs. Actional passives were understood better than experientials, with no difference among the subcategories of experiential verbs, and no effect of verb frequency or regularity. Response distributions for each verb type did not show two populations of subjects – one knowing and the other not knowing the passive – but approximately unimodal distributions whose mean increased with age. Experiment II studied preschoolers. Again, the actional passives were systematically easier than the experientials, and again, for neither verb type did the response distributions show two distinct subject populations, one competent and the other incompetent. The forms of the distributions cannot be wholly accounted for by fluctuating attention to cues to passivization, but indicate that many children have partial knowledge of the passive (increasing with age). A hypothesis about the nature of this partial knowledge accounts for the gradual acquisition and the difference between the verb types.

Seventeen of a sample of 30 precocious talkers aged 1;8 produced at least one pronoun reversal (I/you) during unstructured play. This finding led to an examination of the role of cognitive and linguistic individual differences as well as contextual factors and processing complexity as determinants of pronoun reversal. Contrary to predictions derived from previous hypotheses, there were few differences between reversers and non-reversers, other than higher use of second person forms by reversers. Reversals were more likely to occur in certain contexts: semantically reversible predicates with two noun phrases, and in imitations (though the rate of imitation was lower overall in reversers). We propose that pronoun reversals commonly result from a failure to perform a deictic shift, which is especially likely when children's psycholinguistic processing resources are taxed. Children who did not produce any pronoun reversals tended to avoid pronoun use, especially second person forms. Overt reversal may thus reflect a risk-taking approach to language acquisition, which may be particularly characteristic of precocious children.

Many children learn language, in part, from the speech of non-native speakers who vary in their language proficiency. To investigate the influence of speaker proficiency on the quality of child-directed speech, 29 mothers who were native English speakers and 31 mothers who were native speakers of Spanish and who reported speaking English to their children on a regular basis were recorded interacting with their two-year-old children in English. Of the non-native speakers, 21 described their English proficiency as ‘good’, and eight described their English proficiency as ‘limited’. ANCOVAs, controlling for differences in maternal education and child language level, revealed significant effects of group on lexical and grammatical properties of child-directed speech that the literature has identified as positive predictors of child language development. These results suggest that the child-directed speech of native speakers and non-native speakers with good proficiency provide a richer database for language acquisition than the child-directed speech of speakers with limited proficiency.

Children's overextensions (e.g. referring to a pomegranate as apple) raise intriguing questions regarding early word meanings. Specifically, how do object shape, taxonomic relatedness, and prior lexical knowledge influence children's overextensions? The present study sheds new light on this issue by presenting items that disentangle the three factors of shape, taxonomic category, and prior lexical knowledge, and by using a novel comprehension task (the screened-alternative task) in which children can indicate negative exemplars (e.g. which items are notapples). 49 subjects in three age groups participated (Ms=2;0, 2;6, and 4;5). Findings indicate: (1) Error patterns differed by task. In production, errors were overwhelmingly due to selecting items that matched the target word in both shape and taxonomic relatedness. In comprehension, more errors were based on either shape alone or taxonomic relatedness alone, and the nature and frequency of the overextensions interacted with prior lexical knowledge. (2) Error patterns also differed markedly based on the word being tested (apple vs. dog), in both comprehension and production. (3) As predicted, errors were more frequent in production than comprehension, though only for children in the two younger age groups. Altogether, the study indicates that overextensions are not simply production errors, and that both taxonomic relatedness and object shape play a powerful role in early naming errors.

Studies of locatives suggest regularities in order and age of acquisition, including systematic changes in context of use for behind and in front of. The present investigation extends earlier work by utilizing more naturalistic elicitation procedures and exploring an early use of behind and in front of with large reference objects. Thirty-three children, ages 2; 7 to 4; 7, told puppets where to look for missing objects. Results indicate an order of acquisition for English locatives which is consistent with prior reports. However, the puppet story method elicited given locatives at younger ages, and the first uses of behind occurred with large, non-featured reference objects. The patterns of use for behind and in front of suggest an acquisition process in which new conceptual resources lead to the re-analysis of object configurations and thus to new aspects of meaning.

Recent studies suggest a specific relationship between the acquisition of the word ‘gone’ and the development of the object concept. A longitudinal study investigated whether there is a similar relationship between the acquisition of words that encode success and failure, such as no, uh-oh and there, and the development of means–ends skills. A cross-sectional study investigated both these relationships. The results suggest that children acquire the word gone after they solve simple invisible displacement tasks but before they solve serial invisible displacement tasks. They also show that children acquire success/failure words after they use insight to solve the problem of the string but before they use insight to solve more difficult means–ends problems. These sequences cannot be explained in terms of age, general cognitive development or general linguistic development. It is argued that gone encodes a concept related to the concepts that underlie success on invisible displacement tasks, and that success/failure words encode concepts related to the concepts that underlie the development of insight. Children seem to acquire words that encode concepts they have just developed or are in the process of developing. These results suggest that there are strong and specific links between the acquisition of particular types of meanings and particular cognitive achievements. Several alternative explanations for these early links between semantic and conceptual development are proposed.

The acquisition of reference involves both morphosyntax and pragmatics. This study investigates whether Dutch, English and French two- to three-year-old children differentiate in their use of determiners between non-specific/specific reference, newness/givenness in discourse and mutual/no mutual knowledge between interlocutors. A brief analysis of the input shows a clear association between form and function, although there are some language differences in this respect. As soon as determiner use can be statistically analyzed, the children show a relatively adult-like pattern of association for the distinctions of non-specific/specific and newness/givenness. The distinction between mutual/no mutual knowledge appears later. Reference involving no mutual knowledge is scarcely evidenced in the input and barely used by the children at this age. The development of associations is clearly related to the rate of determiner development, the French being quickest, then the English, then the Dutch.

This paper examines the role of age, working memory span and phonological ability in the mastery of ten different grammatical constructions. Six- through eleven-year-old children (n=68) and adults (n=19) performed a grammaticality judgment task as well as tests of working memory capacity and receptive phonological ability. Children showed early mastery of some grammatical structures (e.g. word order, article omissions) while even the oldest children differed from adults on others (e.g. past tense, third person singular agreement). Working memory capacity and phonological ability accounted for variance in grammaticality judgments above and beyond age effects. In particular, working memory capacity correlated with structures involving verb morphology and word order; phonological ability was important for structures with low phonetic substance. Children's relative difficulty with the different constructions showed parallels to adult performance under memory load stress, indicating working memory capacity may be a limiting factor in their performance. Implications for performance by memory and phonologically impaired populations are discussed.