Grammatical characteristics of Swedish children with SLI

Spontaneous speech samples from 10 Swedish children were collected and analyzed grammatically. The subjects consisted of 5 children with SLI and 5 MLU matched controls with normal grammatical development. The children with SLI differed significantly from the controls in their more restricted usage of word order patterns and in number of grammatical errors. As in studies on English-speaking children with SLI, the Swedish children with SLI had a large number of omissions of grammatical morphemes. Verb-related errors were more common than noun-related errors. Contrary to reports on children with SLI acquiring other languages, however, word order errors were also very common in the Swedish children with SLI. A restricted usage of word order pattern in combination with errors of word order indicates that not only morphological deficits but also syntactic difficulties can be found in children with SLI relative to MLU controls, depending on the target language. The findings show the importance of cross-linguistic comparisons of children with SLI.     

A parallel licensing model of normal slips and phonemic paraphasias

A model of phonological processing in speech production based on prosodic licensing can capture general patterns of errors found in both normal and aphasic speech. All segments must be licensed by some prosodic category (syllable, nucleus, or rime) in order to be produced. Constraints on licensing, including both phonotactic and binding constraints, ensure that only correct licensing associations are retained. A computer simulation of our model produces utterances in qualitative agreement with human speech error data. Phonemic puraphasias are claimed to arise from the same mechanisms as normal speech errors; the difference being only a matter of disturbance of the lexical retrieval and licensing processes. The fact that these errors, which can involve gross disruption of the segmental sequence, still produce phonotactically well-formed strings is a direct consequence of the syllabic licensing that forms the core of our theory of speech production.     

Acoustic cues to grammatical structure in infant-directed speech: cross-linguistic evidence

Several theorists have suggested that infants use prosodic cues such as pauses, final lengthening, and pitch changes to identify linguistic units in speech. One potential difficulty with this proposal, however, is that the acoustic shape of an utterance is affected by many factors other than its syntax, including its phonetic, lexical, and discourse structure. This has raised questions about how the infant could use timing and pitch as cues to any aspect of linguistic structure without simultaneously factoring out other effects. Acoustic analyses of connected samples of spontaneous speech addressed to 13.5-14-month-old infants by American English- and by Japanese-speaking mothers revealed that both utterance- and phrase-level acoustic regularities were large enough to be detected in spontaneous speech without correcting for other influences on the same acoustic features. (1) Utterance-final vowels were lengthened and underwent exaggerated pitch changes in both languages, and (2) local acoustic changes in duration (English) or pitch (Japanese) were reliably associated with some phrase boundaries within utterances. These findings suggest that a naive listener could estimate a rough prosodic template for each language based on robust acoustic patterns in observed sentences. We discuss ways in which the learner could combine acoustic and distributional analyses across utterances to acquire language-specific variations in prosodic bracketing cues and to obtain indirect perceptual evidence for the internal structure of utterances.     

Effects of prosodic stress and serial position on syllable omission in first words.

The authors documented syllable omission in one child's multisyllabic vocabulary from 10 to 20 months of age to evaluate L. Gerken's (1991, 1994, 1994) proposal that children organize their productions according to a trochaic metrical (strong–weak) template and omit syllables from target utterances that do not conform to this pattern. The trochaic template hypothesis was not supported by these early productions. Results indicated that the likelihood of producing a target syllable was influenced primarily by the strength of the prosodic stress placed on it and secondarily by its serial order within a word. Over time, the child demonstrated an increasing ability to include syllables with weaker prosodic stress in multisyllabic productions. Omissions became much less common with the onset of 2-word speech. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Processing segmental and prosodic information in Cantonese word production.

Five experiments were conducted to investigate how subsyllabic, syllabic, and prosodic information is processed in Cantonese monosyllabic word production. A picture-word interference task was used in which a target picture and a distractor word were presented simultaneously or sequentially. In the first 3 experiments with visually presented distractors, null effects on naming latencies were found when the distractor and the picture name shared the onset, the rhyme, the tone, or both the onset and tone. However, significant facilitation effects were obtained when the target and the distractor shared the rhyme + tone (Experiment 2), the segmental syllable (Experiment 3), or the syllable + tone (Experiment 3). Similar results were found in Experiments 4 and 5 with spoken rather than visual distractors. Moreover, a significant facilitation effect was observed in the rhyme-related condition in Experiment 5, and this effect was not affected by the degree of phonological overlap between the target and the distractor. These results are interpreted in an interactive model, which allows feedback sending from the subsyllabic to the lexical level during the phonological encoding stage in Cantonese word production. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Specific language impairment: preliminary investigation of factors associated with family history and with patterns of language performance

To examine patterns that might suggest etiologic subgroups of specific language impairment (SLI), information, including history of speech-language-learning (SLLD) problems in family members, was obtained on 53 children with SLI aged 4 to 9 1/2 years. The results led to the generation of a number of hypotheses for future research. In particular, the findings suggested that family history is related to pattern of language performance. In comparison with children who had both expressive and receptive language deficits, children with deficits in only expressive language had a higher proportion of affected family members (.47 vs. .22), of affected mothers (.57 vs. .17), and of affected siblings (.53 vs. .27). These and other findings are discussed in terms of their consistency with other data, hypotheses relative to explanations of SLI, and their implications for further research.     

A dyspraxic deficit in specific language impairment and developmental coordination disorder? Evidence from hand and arm movements

The extent to which children with either specific language impairment (SLI) or developmental coordination disorder (DCD) could be considered dyspraxic was examined using three tasks involving either familiar, or unfamiliar actions. SLI is diagnosed in children who fail to develop language in the normal fashion for no apparent reason, while the DCD diagnosis is applied to a child who experiences problems with movement in the absence of other difficulties. Seventy-two children aged between 5 and 13 years participated, falling into one of four groups: (1) children with specific language impairment (SLI), (2) children with developmental coordination disorder (DCD), (3) age-matched control children, and (4) younger control children. The performance of the clinical groups resembled that of younger normally developing children. Children with SLI, DCD, and the younger controls showed significant difficulty on the task requiring the production of familiar, but not unfamiliar postures. The deficit observed in the SLI group is particularly striking because it was seen both in those with and those without recognized motor difficulties.     

Arsenic burden among children in industrial areas of eastern Germany

Several accounts of specific language impairment (SLI) in children have appeared in the recent literature. One of the most explicit is that of Locke. The purpose of the present investigation was to evaluate some of the details of Locke's proposal. In the first of two studies, it was found that children with SLI who were limited to single-word utterances showed deficits in their lexical comprehension. In the second study, a number of children with SLI who had reached the grammatical stage of development showed age-appropriate levels of lexical comprehension. Although the first of these findings was in keeping with Locke's account, the second was not. Additional provisions for this proposal are suggested.     

Evidence for a grammar-specific deficit in children

BACKGROUND: Specific language impairment (SLI) is a disorder in which language acquisition is impaired in an otherwise normally developing child. SLI affects around 7% of children. The existence of a purely grammatical form of SLI has become extremely controversial because it points to the existence and innateness of a putative grammatical subsystem in the brain. Some researchers dispute the existence of a purely grammatical form of SLI. They hypothesise that SLI in children is caused by deficits in auditory and/or general cognitive processing, or social factors. There are also claims that the cognitive abilities of people with SLI have not yet been sufficiently characterised to substantiate the existence of SLI in a pure grammatical form. RESULTS: We present a case study of a boy, known as AZ, with SLI. To investigate the claim for a primary grammatical impairment, we distinguish between grammatical abilities, non-grammatical language abilities and non-verbal cognitive abilities. We investigated AZ's abilities in each of these areas. AZ performed normally on auditory and cognitive tasks, yet exhibited severe grammatical impairments. This is evidence for a developmental grammatical deficit that cannot be explained as a by-product of retardation or auditory difficulties. CONCLUSIONS: The case of AZ provides evidence supporting the existence of a genetically determined, specialised mechanism that is necessary for the normal development of human language.     

Creation of prosody during sentence production

Phrase-final words tend to be lengthened and followed by a pause. The dominant view of prosodic production is that word lengthening and pausing reflect the syntax of a sentence. The author demonstrates that, instead, lengthening and pausing reflect a distinctly prosodic representation, in which phonological constituents are arranged in a hierarchical, nonrecursive structure. Prosodic structure is created without knowledge of words' phonemic content. As a result, within a single sentential position, greater word lengthening necessitates shorter pauses, but across positions, word and pause durations show a positive correlation. The author presents a model of prosodic production that describes the process of prosodic encoding and provides a quantitative specification of the relation between word lengthening and pausing. This model has implications for studies of language production, comprehension, and development.     

Acoustic analysis of lexical tone in Mandarin infant-directed speech.

Using Mandarin Chinese, a "tone language" in which the pitch contours of syllables differentiate words, the authors examined the acoustic modifications of infant-directed speech (IDS) at the syllable level to test 2 hypotheses: (a) the overall increase in pitch and intonation contour that occurs in IDS at the phrase level would not distort lexical pitch at the syllable level and (b) IDS provides exaggerates cues to lexical tones. Sixteen Mandarin-speaking mothers were recorded while addressing their infants and addressing an adult. The results indicate that IDS does not distort the acoustic cues that are essential to word meaning at the syllable level; evidence of exaggeration of the acoustic differences in IDS was observed, extending previous findings of phonetic exaggeration to the lexical level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Language and Williams syndrome: how intact is "intact"?

It has been claimed that Williams syndrome (WS), a rare neurodevelopmental disorder, is characterized by serious cognitive deficits alongside intact language. The syndrome is often used as a prime example of the modularity of an innate faculty for morphosyntactic rules. We challenge this claim and hypothesize that morphosyntax, although surprisingly good given WS level of mental retardation, is by no means intact. We make an initial test of this hypothesis through an analysis of the receptive language of a group of English-speaking WS individuals on a standardized morphosyntactic test. We then present an experimental study of expressive language that examines grammatical gender assignment in French-speaking WS patients. Despite a Verbal Mental Age selected to be higher than the chronological age of the young control group, these people with WS continue even in adulthood to show clear-cut deficits in their production of an aspect of morphosyntax that normal children acquire effortlessly very early. The results of the 2 studies, one focusing on receptive language and the other on expressive language, challenge the notion that comprehension and use of morphosyntactic rules in WS individuals are intact. The Within-domain dissociations regarding the use of grammatical gender assignment across several sentence clements and their difficulties in understanding embedded sentences-two quintessentially linguistic skills-suggest that we must rethink the notion of spared, modular, language capacities in Williams syndrome. We conclude that WS language follows a different path to normal acquisition and may turn out to be more like second language learning.     

The effect of presentation rate on serial memory in young children with specific language impairment

The study examined the serial memory ability of a group of preschool children with specific language impairment (SLI) who were compared to age and language control groups. The children were asked to recognize serial patterns under short and long presentation durations. The subjects were presented with images of common objects (that appeared to be easily recoded into a phonological form) and iconic images of scribble drawings and unfamiliar faces (that did not appear to invite recoding). Under long presentation conditions, the performance of children with SLI resembled that of their age-matched peers on all 3 types of tasks. However, under short presentation conditions, children with SLI performed worse than their age-matched peers on all 3 tasks (and similarly to their language-matched peers). The performance of the children with SLI declined dramatically in all conditions when the items were presented for a brief period. If the serial memory deficits of young children with SLI were specific to phonological processing, their performance on recognizing the pattern of common objects should have been impaired, but not their performance with other visual tasks that are less likely to be recoded. Instead, serial memory in children with SLI was affected by presentation duration across tasks. The findings suggest that recognizing serial patterns is dependent, in part, on the speed of processing serial information. The findings are discussed in relation to models of limited capacity processing.     

Information processing by school-age children with specific language impairment: evidence from a modality effect paradigm

School-age children with specific language impairment (SLI) and age-matched controls were tested for immediate recall of digits presented visually, auditorily, or audiovisually. Recall tasks compared speaking and pointing response modalities. Each participant was tested at a level that was consistent with her or his auditory short-term memory span. Traditional effects of primacy, recency, and modality (an auditory recall advantage) were obtained for both groups. The groups performed similarly when audiovisual stimuli were paired with a spoken response, but children with SLI had smaller recency effects together with an unusually poor recall when visually presented items were paired with a pointing response. Such results cannot be explained on the basis of an auditory or speech deficit per se, and suggest that children with SLI have difficulty either retaining or using phonological codes, or both, during tasks that require multiple mental operations. Capacity limitations, involving the rapid decay of phonological representations and/or performance limitations related to the use of less demanding and less effective coding and retrieval strategies, could have contributed to the working memory deficiencies in the children with SLI.     

An electrophysiological study of infants' sensitivity to the sound patterns of English speech

The study explores 10- to 11-month-old infants' sensitivity to the phonological characteristics of their native language. Event-related potentials (ERPs) were obtained for tones that were superimposed on two versions of a story: an Unmodified version containing normal English function morphemes, and a Modified version in which the prosodic and segmental properties of a subset of function morphemes were changed to make them atypical. The 11-month-olds exhibited significantly lower amplitude ERPs to the tones during the Modified story than to the Unmodified story, whereas the 10-month-olds showed no differences. These results suggest that the 11-month-olds discriminated the two versions of the story based on their representations of the phonological properties of English. Further, the tone-probe ERP method can successfully be used to study the development of speech perception in the pre-linguistic infant.     

Disconnected phonology: a linguistic analysis of phonemic jargon aphasia

This paper reports on indications of the nature of the neurolinguistic connection between phonological and lexical components of language, based on a case of phonemic jargon aphasia. Following bihemispheric embolic infarcts, the subject presented with severe fluent aphasia, characterized by fluent strings of phonemes, with virtually no intelligible utterances. Despite nearly total jargonized output, the fundamental phonological processes of speech were largely intact. Specifically she demonstrated: (1) English phonotactics and English stress-timed rhythmic principles, (2) aspirated stops word-initially and glottalized stops word-finally, (3) utterance final declination of pitch, and (4) stressed syllable vowel lengthening. Additionally, regional-specific (Southern American English) phonological processes, including monophthongization, in-gliding, and front vowel backing, were also preserved. Overall, the investigation reveals an example of an intact phonological rule system operating on a grossly disturbed input (lexical representation).     

Lexical learning by children with specific language impairment: effects of linguistic input presented at varying speaking rates

The purpose of this study was to investigate the impact of speaking rate variations in the linguistic input provided to children during a novel word learning task. Thirty-two school-age children participated in this investigation, including 16 children with specific language impairment (SLI) and 16 normal language (NL) controls matched on mental age (MA). The younger half of the NL group also served as a vocabulary level comparison for the older half of the children with SLI. No significant rate effects were found for comprehension of novel words, with all children performing at relatively high levels of accuracy. The group with SLI demonstrated the same recognition accuracy pattern as MA matched controls for target labels versus phonetically similar/dissimilar foils only for words trained at slow rate. Rate effects were most pronounced for items with the highest difficulty level, namely production of novel words. Children with SLI produced significantly fewer words that had been presented at fast rate during training than NL children matched on mental age or vocabulary level. Individual differences and production error patterns on fast rate items were examined. The finding that variations in speaking rate had a disproportionate impact upon word learning for children with SLI was interpreted within a framework of limited processing capacity.     

Phonetic profiles of toddlers with specific expressive language impairment (SLI-E)

Spontaneous language samples of 30 24-month-old toddlers diagnosed with Specific Expressive Language Impairment (SLI-E) were compared with samples produced by an age-matched group of 30 typically developing toddlers. Vocalization patterns, phonetic inventories, and syllable formation patterns were compared. Toddlers with SLI-E vocalized significantly less often than their typically developing peers, had proportionately smaller consonantal and vowel inventories, and used a more restricted and less mature array of syllable shapes. Although the mean incidence of phoneme usage varied significantly in all comparisons, profiles of consonant usage were similar between the two groups for initial phoneme usage, but considerably different for final consonant closure. Such patterns of vocal and phonetic behavior confirm earlier reports of phonetic delay in SLI-E, and suggest that nongrammatical factors contribute to the development of expressive language deficits in toddlers. We further propose a bidirectional model for the expressive deficits in SLI-E, in which the child's limited phonetic capacity interacts with propensities in caretaker interaction to further reduce opportunities for expressive language learning and practice.     

Language in Italian children with Down syndrome and with specific language impairment.

This article compares lexical and grammatical abilities of a mental-age-matched sample of Italian preschoolers with Down syndrome (DS), specific language impairment (SLI), or typical development. Results showed that the children with DS or with SLI performed significantly worse than did the typically developing children. Although no significant differences emerged in lexical abilities and morphosyntactic comprehension abilities between the children with DS or with SLI, significant differences did emerge in morphosyntactic production capacities. Qualitative analysis of the morphosyntactic errors revealed strong similarities between the two groups. The results are discussed in terms of the role of verbal memory abilities and the linguistic features of Italian. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The development of phonological awareness in preschool children.

A short-term longitudinal study was carried out on a group of 67 preschool children. At three points in time over a 12-month period, the children were given tests measuring their syllable, rime, and phoneme awareness, speech and language skills, and letter knowledge. In general, children's rime skills developed earlier than their phoneme skills. Structural equation models showed that articulatory skills and syllable and rime awareness predicted later phoneme awareness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)