How do children acquire early grammar and build multiword utterances? A corpus study of French children aged 2 to 4.

In the last 50 years, researchers have debated over the lexical or grammatical nature of children's early multiword utterances. Due to methodological limitations, the issue remains controversial. This corpus study explores the effect of grammatical, lexical, and pragmatic categories on mean length of utterances (MLU). A total of 312 speech samples from high-low socioeconomic status (SES) French-speaking children aged 2-4 years were annotated with a part-of-speech-tagger. Multiple regression analyses show that grammatical categories, particularly the most frequent subcategories, were the best predictors of MLU both across age and SES groups. These findings support the view that early language learning is guided by grammatical rather than by lexical words. This corpus research design can be used for future cross-linguistic and cross-pathology studies.

Productivity of lexical categories in French-speaking children with cochlear implants.

The productivity of lexical categories was studied longitudinally in a sample of 17 young hearing-impaired French-speaking children with cochlear implants. Age of implantation ranged from 22 months to 76 months. Spontaneous speech samples were collected at six-month intervals over a period of 36 months, starting at the one-word stage. Four general measures of their linguistic production (number of utterances, verbal fluency, vocabulary, and grammatical production) as well as 36 specific lexical categories, according to the CHILDES codes, were computed in terms of tokens, i.e., total number of words. Cochlear-implanted children (CI) were compared to a French database of normally hearing children aged 2-4 compiled by the first author. Follow-up results indicate that, at the two-year post-implantation follow-up, noun, and verb morphology was significantly impaired. At the three-year follow-up, the cochlear-implanted group had recovered on adjectives, determiners and nouns, main verbs, and auxiliaries. The two groups differed significantly in processing locative adverbs, prepositions, pronouns, and verbs (infinitive verb, modal, and modal lexical), but individual variability within the cochlear-implanted group was substantial. Results are discussed in terms of recovery and developmental trends and variability in the acquisition of lexical categories by French children two years and three years post-implantation.

Language evolution in children with cochlear implants.

The capacity to incorporate significant words into the existing vocabulary and to use these words to form sentences with more mature syntactic structures emerges over a considerable time course in young deaf children who have undergone a cochlear implantation. The purpose of this follow-up study is to document the nature and time span of language production--in morphosyntactic and lexical skills--when a child's first experience with language sounds is provided artificially through electrical stimulation. To examine the development of these two aspects of linguistic processing, five deaf French children, all enrolled in similar postimplantation educational settings, were individually assessed at 6-month intervals over a period of 18 months. Computerized analyses were derived from their spontaneous speech in a 20-min standardized play session. Results for mean length of utterance and vocabulary revealed gradually improving performance for most children, in spite of the generally low starting point. Both measures of production nevertheless remained well below the norms established for normally hearing children. Although the achievement of higher production scores, which underlies more effective interpersonal exchanges, is evident after only 1 year of device use, it is clear that improvement does not always occur at the same pace, as shown by two of the children. This emphasizes the importance of longitudinal studies in documenting intersubject variability and intrasubject stability throughout the experience with an implant.

Acquisition of lexical morphology in simple partial epilepsy.

In the study of language acquisition following early brain damage, results have been divergent. On one hand, some studies claim that language eventually resumes to normal, whereas, on the other hand, studies show lasting deficits throughout development. Discrepancies in the results could arise from different etiologies and tests used. This study attempts to determine the extent to which the development of verb production is affected in later development in children who had simple partial epilepsy (SPE). Measures of diversity and fluency of three verb types, namely main verbs, auxiliary and copula verbs, and nonfinite verbs were used on three children diagnosed as SPE and compared to control groups. Our main results show a limited production of auxiliary verbs. Further analysis of their productions suggest a telegraphic style of speech, as reflected by a superior production of nonfinite verb type compared with normal children. These findings are interpreted as reflecting long-lasting consequences of early brain damage with respect to language development.

Automatic disambiguation of morphosyntax in spoken language corpora.

The use of computer tools has led to major advances in the study of spoken language corpora. One area that has shown particular progress is the study of child language development. Although it is now easy to lexically tag every word in a spoken language corpus, one still has to choose between numerous ambiguous forms, especially with languages such as French or English, where more than 70% of words are ambiguous. Computational linguistics can now provide a fully automatic disambiguation of lexical tags. The tool presented here (POST) can tag and disambiguate a large text in a few seconds. This tool complements systems dealing with language transcription and suggests further theoretical developments in the assessment of the status of morphosyntax in spoken language corpora. The program currently works for French and English, but it can be easily adapted for use with other languages. The analysis and computation of a corpus produced by normal French children 2-4 years of age, as well as of a sample corpus produced by French SLI children, are given as examples.

How children build their morphosyntax: the case of French.

Early morphosyntax is very rich and uniform in young French-speaking children. The present study aims to give a thorough analysis of the morphosyntax produced at the outset of multi-word speech, with a classification of free language produced at 2;0 by 27 French-speaking children. The corpus was fully tagged by an automatic part-of-speech tagger. A classification performed with words taken in isolation shows a clear difference between the categories used in single-word utterances and those used in multi-word utterances. A classification performed with word sequences reveals surprisingly adult-like sequences of syntactic categories and words; the non-adult combinations are few in a French child's language. The very successful use of the tagger demonstrates the morphosyntactic coherence of the child's speech. When compared with adult language, the quantitative results, and more precisely the data concerning regularity and error types, contribute to the documentation of all the specificities of the emerging morphosyntax in normally developing French children.

Language development in a child with left hemispherectomy.

A longitudinal study of a left hemispherectomized boy (AB) was conducted to document linguistic evolution and maturation and determine the extent to which right hemisphere processes allow development of language. Resection of the left hemisphere occurred at age 5 years 6 months, following intractable epilepsy. Tests of language comprehension (pointing, understanding of prepositions, understanding of narratives) and production (naming, repetition, lexical diversity, grammatical production) were administered at ages 6:2, 6:4, 6:6, and 6 years 9 months. Observations showed little progress, if any, in most aspects of linguistic performance. In contrast to studies with left-hemispherectomized children, AB showed only a modest expansion of the semantic lexicon and the phonological repertoire more than a year after the surgical intervention. These observations indirectly suggest (1) poor functional involvement of the right hemisphere in the development of adequate linguistic abilities, (2) the necessary integrity of the LH for adequate development of language, or (3) that variations in individual brain maturation rates may account for AB's linguistic progress.

Asynchronous language acquisition in developmental dysphasia.

A longitudinal study was conducted to document and compare evolution of children with linguistic acquisition impairment. To determine whether development of the analytic mechanisms underlying linguistic processing occured in similar fashion, two children with mixed developmental dysphasia were assessed from 4 to 5:6 years of age with psycholinguistic tests at 6-months interval. Spontaneous speech and language production (consonant repertory in initial word position, MLU, and lexical diversity) were investigated in a standardized symbolic play context. The phonologic and lexico-morphologic evolution analyses revealed a marked improvement in motor control of phonology and in the application of morphosyntaxic rules in child 1, whereas child 2 was still impaired in phonology and morphosyntax. The singular developmental changes in spontaneous speech results indicate dynamic relationships between various language production facets and variability in the kind of deficit and lexical automation presented by these children. These contrasts in the evolution of language production profiles between child 1 and child 2 also underline the importance of longitudinal studies in the analysis of the atypical linguistic processing paths used by children with developmental dysphasia.

Neuromotor development and language processing in developmental dyspraxia: a follow-up case study.

A longitudinal study of a child (MV) with developmental verbal dyspraxia was conducted to determine to what extent language development and motor performance in this clinical diagnosis followed a similar course of maturation. Patient MV was observed for two years from the age of 5 years and 6 months. Initially, this young patient exhibited unintelligible and atypical speech production (multiword utterances without consonants), delay in balance and coordination, and impairments in rhythmic tasks; but she was otherwise developing normally with no intellectual impairment or behavioral disorder. MRI scans showed moderately enlarged ventricles, a thin, incompletely myelinated corpus callosum and intact basal ganglia. Two years later, MV's performance was nearly normal only in comprehension aspects of language. In contrast, production aspects of language and speech and neuromotor development showed very little improvement after two years. These observations first suggest that development of receptive and expressive domains within language may be asynchronous, and that the progression of motor control of language appears to follow a parallel course to neuromotor development.

Language development in children with simple-partial left-hemisphere epilepsy.

The nature of cerebral involvement in the acquisition of language was addressed in this longitudinal study of children with an early diagnosis of epilepsy with simple-partial seizures (SPE) and with epileptogenic foci localized in the left frontal (LF) lobe. Yearly evaluations of six SPE-LF children on tests of linguistic comprehension (pointing, understanding of narrative, and understanding of prepositions) and production (repetition, lexical diversity, and grammatical production) were carried out between the ages of 3 and 8 years and compared to those of large samples of control children on the same tasks and at each age level. Linguistic production of all children were transcribed, coded, and analyzed using the Child Language Data Exchange System (MacWhinney & Snow, 1991). Individual evolution trajectories revealed that SPE-LF children showed a clear dissociation in linguistic performance between comprehension and production. Linguistic comprehension gradually improved to reach normal performance levels by age 7 while linguistic production, even at later stages, remained quite poor. This dissociation in the development of linguistic performance in SPE-LF children suggests a complex interplay between brain maturation dynamics and dysfunction modulating the succession of stages in language development. The observed persistent deficits in specific aspects of linguistic performance argue for an early involvement of the anterior areas of the left cerebral hemisphere in the production of language.

Language and motor development in pre-term children: some questions.

A cohort of 37 pre-term children was assessed for both morphosyntactical and for vocabulary skills at the age of 2 and again at the age of 3 years and 6 months. They were compared with two comparison groups of full-term children (adjusted age and chronological age). The results indicated (1) a clear asynchrony between the two components of language production assessed at both ages, (2) an accurate prediction of language delay at age 2 for pre-term children (35% of pre-term children were detected for morphosyntax as measured by Mean Length of Utterance and 27% of pre-term children were detected for vocabulary as measured by the number of different words) and, (3) no evidence on the relationship of language and motor development as measured by formal tests. Such findings strongly challenge the validity of standardized developmental tests and support to a certain extent the hypothesis that language development is independent of motor skills. A neurodevelopmental assessment is suggested.

A cross-linguistic study of article use by children with specific language impairment.

Children with specific language impairment (SLI) often show limitations in grammatical morphology that exceed their problems in other areas of language. One factor contributing to this difficulty might be the relatively brief durations of many grammatical morphemes. In the present study, this factor was explored by examining the use of articles by a group of French-speaking children with SLI. French differs from other languages studied to date in that the differences in duration between stressed syllables and unstressed syllables, such as articles, are much smaller. The data revealed that French-speaking children with SLI used articles with relatively high percentages equivalent to those seen for a group of normally developing French-speaking children matched according to mean length of utterance. In addition, the percentages seen for the French-speaking children with SLI were substantially higher than those observed for children with SLI who were acquiring Italian and English.

Individual differences in the production of word classes in eight specific language-impaired preschoolers.

The production of word classes in eight 53-62-month-old specific language-impaired (SLI) children was described and compared with that of 30 normal 24-33-month-old children in the same play situation. SLI subjects and nonimpaired children were selected within specified mean length of utterance ranges (low MLU versus high MLU). Production of word classes by subjects was evaluated in order to determine (1) whether SLI children showed a similar or a different word-class profile among themselves and when compared with non-impaired children and (2) whether MLU related to word classes would be useful as a single clinical index in assessment of language acquisition. Results showed that scores of SLI children in production of word classes reflect important individual differences among subjects. In the high-MLU sample, all SLI children produced each word class relatively within the same range as the nonimpaired group. In the low-MLU sample two SLI children were very different in their word-class profile and individual differences were further confirmed by a discriminant function analysis. Correlations between MLU and word classes were significant in nonimpaired children for all variables except Questions and Onomatopoeia and were only significant in SLI children for Verbs, Prepositions, and Personal Pronouns. Such findings contribute support to the view that there is "deviant" pattern of language in SLI children and once again questions whether MLU is one of the best discriminating indicators to use in the clinical assessment of language organization.

A follow-up case study of transitory developmental apraxia of speech: 'L'enfant à voyelles'.

It is well known that the acquisition of consonants can be a more difficult developmental process than of vowels. In this study the authors describe a case of 'transitory developmental apraxia of speech' (TDAS) in which a French-speaking child, although he acquired the whole vowel system, showed a significant delay in consonant acquisition and usage. The results of systematic observations and assessments of general cognitive and specific language functioning cover a period of 4 years (age 3:8 to 7:1l), from first clinical assessment to evidence of a good academic achievement. It is argued that this case demonstrates an unusual example of TDAS. The language deficits observed could not be attributed to oromotor, neurological, cognitive or intellectual deficits. The findings here also raise crucial questions concerning the origins of such a speech disorder and why it is transient in nature.

A developmental exploration of language used to accompany symbolic play in young, normal children (2-4 years old).

Observation of play can provide crucial information about a child's developmental level of language. To make this information available categorization and measurement are necessary. By defining, from a cognitive and pragmatic point of view, separate but parallel measures of play and language it was possible to define four different levels of symbolic functioning: representational play; conceptual play; programmatic play; and script play. Careful longitudinal descriptions of language used to accompany symbolic play of ten 2-4-year-old children are presented. Interesting developmental trends in play and cognitive and pragmatic organization of language were found. Gradually language production was considered as the primary mode for symbolic expression between the ages of 2;6 (2 years; 6 months) and 3 years. Language production increased dramatically between the ages of 3 and 3;6, and became better differentiated from the play context. The scientific study of child language using an analytic tool, such as a play procedure, to describe and analyse spontaneous production of spoken language, with a cognitive and pragmatic framework contributes not only a more accurate understanding of normal play and language development, but may also have an efficient clinical value. Suggestions for and implications of exploring components of language used in a standardized play situation are discussed in reference to developmentally disabled children.