A widely held practice in many studies of child language development and disorders has been to employ an easily calculated numerical metric, mean length of utterance measured in morphemes (MLU), as a ‘general index of grammatical development’. While this practice seems to have found acceptance among many students of child language, the usefulness of MLU past Stage II has been assumed but never empirically tested. This study evaluated the grammatical performance and MLU of 18 normally developing 2- and 3-year-old children and found that MLU did not correlate significantly with age (r = 0·26), nor did it discriminate children's profiles of grammatical development.

This study examined the relationship between mothers' speech and the rate of child syntax growth for 22 2½-year-old children whose speech was sampled at two-month intervals over a six-month period. The relations which appeared suggest that linguistic experience does contribute to syntax development, but that the relation between linguistic input and language growth is different for different domains of language and at different points in the course of development. The results further suggest that there are multiple bases to the benefit of input to language acquisition. One mechanism particularly suggested by the findings is that children analyse the distributional properties of the speech they hear and may induce linguistic structure from the relationship between the structural properties of adjacent utterances in discourse.

This study explores the role that gesture plays in the earliest stages of language learning. We describe how one-word speakers use gesture in combination with speech in their spontaneous communications, and interpret gesture presented in combination with speech in an experimental situation. Forty one-word speakers (ages 1;2.22 to 2;4.6) were videotaped in a free-play session which provided data on the child's spontaneous gesture and speech production. The children were also given a comprehension task in which the presence and absence of gesture were systematically varied in relation to speech. We found that (1) all of the children spontaneously produced gestures in combination with speech, and (2) all of the children were able to understand gesture when it was presented in combination with speech, not only when the gesture was redundant with speech but also when the gesture substituted for speech. These data suggest that, even at this young age, gesture naturally forms an integrated system with speech in both production and comprehension.

Many early words encode aspects of plans, that is, actions performed in order to bring about events. Gone and down encode the fact that an action is intended to bring about a certain type of event. There and oh dear encode the success or failure of plans, no encodes the rejection of a plan. More encodes the repetition of a plan. It is argued that the concepts encoded by gone and down are like the concepts that underlie trial- and-error problem-solving and are developed after 12 months. The more abstract concepts encoded by there, oh dear, no and more are associated with the development of insight after 18 months. These early words are acquired because they are relevant to the child's cognitive problems.

This paper presents a large-scale cross-sectional study of Danish children's early language acquisition based on the Danish adaptation of the MacArthur-Bates Communicative Development Inventories (CDI). Measures of validity and reliability imply that the Danish adaptation of the American CDI has been adjusted linguistically and culturally in appropriate ways which makes it suitable for tapping into Danish children's language acquisition. The study includes 6,112 randomly selected children in the age of 0 ; 8 to 3 ; 0, and results related to the development of early gestures, comprehension and production of words as well as grammatical skills, are presented.

Although the role of visual perception is central to many theories of language development, researchers have disagreed sharply on the effects of blindness on the acquisition process: some claim major differences between blind and sighted children; others find great similarities. With audio-and video-recorded longitudinal data from six children (with varying degrees of vision) aged 0; 9–3; 4, we show that there ARE basic differences in early language, which appear to reflect differences in cognitive development. We focus here on early lexical acquisition and on verbal role-play, demonstrating how previous analyses have failed to observe aspects of the blind child's language system because language was considered out of the context of use. While a comparison of early vocabularies does suggest surface similarities, we found that when sighted peers are actively forming hypotheses about word meanings, totally blind children are acquiring largely unanalysed ‘labels’. They are slow to extend words and rarely overextended any. Similarly, although verbal role-play appears early, attempts to incorporate this kind of language into conversations with others reveal clear problems with reversibility – specifically, the ability to understand the role of shifting perspectives in determining word meaning. Examination of language in context suggests that blind children have difficulties in just those areas of language acquisition where visual information can provide input about the world and be a stimulus for forming hypotheses about pertinent aspects of the linguistic system.

Attitudes towards imitation have been coloured by theoretical disputes about the nature of language. But even if language is rule-governed, children may be helped by imitation to discover the rules. This paper reviews evidence for and against imitation as a factor in the acquisition of syntax. The conclusion reached is that the effects of imitation on children's speech are too pervasive for the process to be dismissed as irrelevant. Many idiosyncratic features of children's speech seem to be traceable to imitation interacting with other simple mechanisms. For the author, the important question is no longer whether imitation can help children to acquire syntax, but precisely how a child gradually extracts grammatical information from the repertoire of imitated sequences at his disposal.

This paper examines four mothers' responses to three object-related gestures (pointing, extending objects, and open-handed reaching) by their first-born infants from 0; 9 to 1; 6, and the impact of their responses on the children's transition from gestural to verbal communication. Analysis revealed that the mothers responded differentially to their children's pointing gestures, reciprocating to a greater degree with labels of the indicated objects. The children, in turn, produced more object-labelling words with pointing than with other gestures. In addition, the mothers' labelling responses to pointing significantly predicted the extent of their children's object-naming vocabularies.

Investigators have targeted the onset of reference in children at varying points on the developmental continuum. Their viewpoints seem to be related to issues of the contextual flexibility, content and composition of the lexicon in comprehension and production. This study considered all of the variables in the early vocabularies of 32 children with a mean age of 1; 1·7. An intensive maternal interview was used to obtain data on the words comprehended and produced by the children and the contexts which supported their interpretation and use. The findings pointed to a relative independence between the domains of comprehension and production. Vocabulary size was related to all contextually flexible items in production while only related to the contextually flexible predicates in comprehension. Further, there was evidence for an early version of the referential style that has been reported at later stages of development.

The specificity of infants' phonological representations is examined by comparing their sensitivity to mispronunciations of novel and familiar words, using the preferential looking task. 29 children at 1;2 were trained and tested on familiar and novel word–object pairs. Children showed evidence of sensitivity to mispronunciations of novel and familiar words, indicating detailed phonological representations. Discrepancies between this study and earlier investigations are discussed with reference to differences between habituation and preferential looking tasks.

Speech in children should be viewed as a developing skill. During acquisition the child becomes increasingly capable of organizing linguistic structure at a number of different levels concurrently. One boy seemed to have strategies for simplifying the tasks of speech reception and production. He would incorporate the immediately prior utterance, or some portion of it, intact into his utterance as if to avoid structuring his entire utterance from scratch. Another strategy was to extend his repertoire of structures to express more complex ideas simply by combining two existing structures without reordering any of the elements to match adult syntax. If such strategies are widespread they may account for the recorded facts about the development of children's question forms. Psychological variables, commonly called performance factors, should not be regarded merely as putting restrictions on the extent to which a child's linguistic knowledge can be expressed. Rather, they affect the manner in which syntactic structures develop. Just as the acquisition of linguistic structure is affected by psychological processes, so is the efficiency of these processes affected in its turn by the child's growing linguistic knowledge.

We aimed to disentangle contributions of socio-pragmatic and structural language deficits to narrative competence by comparing the narratives of children with autism spectrum disorder (ASD; n=25), non-autistic children with language impairments (LI; n=23), and children with typical development (TD; n=27). Groups were matched for age (6½ to 15 years; mean: 10;6) and non-verbal ability; ASD and TD groups were matched on standardized language scores. Despite distinct clinical presentation, children with ASD and LI produced similarly simple narratives that lacked semantic richness and omitted important story elements, when compared to TD peers. Pragmatic errors were common across groups. Within the LI group, pragmatic errors were negatively correlated with story macrostructure scores and with an index of semantic–pragmatic relevance. For the group with ASD, pragmatic errors consisted of comments that, though extraneous, did not detract from the gist of the narrative. These findings underline the importance of both language and socio-pragmatic skill for producing coherent, appropriate narratives.

Echolalia is a pervasive phenomenon in verbal children with autism, traditionally conceived of as an automatic behavior with no communicative function. However, recently it has been shown that echoes may serve interactional goals. This article, which presents a case study of a six-year-old child with autism, examines how social interaction organizes autism echolalia and how repetitive speech responds to discernible interactional trajectories. Using linguistic, discourse, and acoustic analyses, we demonstrate that the child is able to mobilize echolalia to mark different stances, through the segmental and suprasegmental modulation of echoes. We offer an interpretive framework that deepens our understanding of the complex interactions that children with autism can engage in by using echoes, and discuss the implications of this perspective for current views of atypical language development in autism.

Previous research has shown that children go through a stage in which they know that the number words each refer to a distinct numerosity, yet do not know WHICH numerosity each number word picks out (Wynn, 1992). How do children attain this level of knowledge? We explore the possibility that particular properties of how number words are used within sentences inform children of the semantic class to which they belong. An analysis of transcripts of the spontaneous speech of three one- and two-year-old children and their parents (from the CHILDES database; MacWhinney & Snow, 1990) suggests that the relevant cues are available as input in parents' speech to children, and that children generally honour these properties of number words in their own speech. Implications of this proposal for word learning more generally are discussed.

This research explores the role of phonotactic probability in two-year-olds' production of coda consonants. Twenty-nine children were asked to repeat CVC non-words that were used as labels for pictures of imaginary animals. The CVC non-words were controlled for their phonotactic probabilities, neighbourhood densities, word-likelihood ratings, and contained the identical coda across low and high phonotactic probability pairs. This allowed for comparisons of children's productions of the same coda consonant in low and high phonotactic probability environments. Children were significantly more likely to produce the same coda in high phonotactic probability non-words than in low phonotactic probability non-words. These results are consistent with the hypothesis that phonotactic probability is a predictor of coda production in English. Moreover, this finding provides further evidence for the role of the input and distribution of sound patterns in the ambient language as a basis for phonological acquisition.

This study focuses on children who go through a ‘silent’ period early in the course of second language development, during which they largely cease verbal communication with speakers of the second language (English). Video recordings with radio microphones under natural conditions revealed that most of these children engaged in extensive private speech, which they were found to use for a variety of intrapersonal learning strategies, including (1) repetition of others' utterances, (2) recall and practice, (3) creation of new linguistic forms, (4) paradigmatic substitution and syntagmatic expansion, and (5) rehearsal for overt social performance. Quantity and quality of private speech was related not only to the children's level of cognitive development and the difficulty of the learning task (confirming previous research), but also to the children's social orientation and learning style, and to the domain of knowledge (language) that was being acquired.

We investigated longitudinal relations among gaze following and face scanning in infancy and later language development. At 12 months, infants watched videos of a woman describing an object while their passive viewing was measured with an eye-tracker. We examined the relation between infants' face scanning behavior and their tendency to follow the speaker's attentional shift to the object she was describing. We also collected language outcome measures on the same infants at 18 and 24 months. Attention to the mouth and gaze following at 12 months both predicted later productive vocabulary. The results are discussed in terms of social engagement, which may account for both attentional distribution and language onset. We argue that an infant's inherent interest in engaging with others (in addition to creating more opportunities for communication) leads infants to attend to the most relevant information in a social scene and that this information facilitates language learning.

This study tested the effect of the phoneme's linguistic affiliation (Standard Arabic versus Spoken Arabic) on phoneme recognition among five-year-old Arabic native speaking kindergarteners (N=60). Using a picture selection task of words beginning with the same phoneme, and through careful manipulation of the phonological properties of target phonemes and distractors, the study showed that children's recognition of Standard phonemes was poorer than that of Spoken phonemes. This finding was interpreted as indicating a deficiency in the phonological representations of Standard words. Next, the study tested two hypotheses regarding the specific consequences of under-specified phonological representations: phonological encoding versus phonological processing. These hypotheses were addressed through an analysis of the relative power of distractors. The findings revealed that children's difficulty in accessing Standard Arabic phonemes was due to a difficulty in the phonological encoding of Standard words. We discuss the implications of the findings for language and literacy development in diglossic Arabic.

Expressive language outcomes measured by MLU and the Index of Productive Syntax (IPSyn) at ages 3;0 and 4;0 were investigated in 34 late talkers with normal receptive language identified between 2;0 to 2;7 and 16 typically developing comparison children matched on age, SES, and nonverbal ability. Late talkers made greater gains than comparison children between 3;0 and 4;0 in both MLU and IPSyn raw score. However, when age-standardized z-scores were analysed, the late talkers were about 2·5 standard deviations below comparison children on both measures at both ages. At 3;0, 41% of the late talkers had MLUs above the 10th percentile based on Scarborough's (1990) benchmark sample; by 4;0, 71% did so. Using the IPSyn, a more stringent measure, 34% scored above the 10th percentile at 3;0 and only 29% did so at 4;0. MLU was significantly correlated with the IPSyn at both ages for the late talkers, but only at 3;0 for the comparison children. A converging set of regression analyses indicated no group differences in the predictive relationship between MLU and IPSyn, suggesting that the late talkers were delayed on both measures but not deviant in their development.