Extra-linguistic influences on sentence comprehension in Italian-speaking children with and without specific language impairment.

BACKGROUND: Many children with specific language impairment (SLI) in sentence comprehension. These deficits are usually attributed to limitations in the children's understanding of syntax or the lexical items contained in the sentences. This study examines the role that extra-linguistic factors can play in these children's sentence comprehension. AIMS: Extra-linguistic demands on sentence comprehension are manipulated directly by varying the nature of the materials used. METHODS & PROCEDURES: Forty-five Italian-speaking children participated: 15 with SLI (mean age = 4;5), 15 typically developing children matched for age (TD-A, mean age = 4;5), and 15 younger typically developing children matched according to language comprehension test scores (TD-Y, mean age = 3;9). The children responded to sentence comprehension items that varied in their length and/or the number and type of foils that competed with the target picture. OUTCOMES & RESULTS: The TD-A children were more accurate than the TD-Y children and the children with SLI, but, for all groups, accuracy declined when task demands increased. In particular, sentences containing superfluous adjectives (e.g., Il topo bello copre l'uccello allegro, 'The nice mouse covers the happy bird' where all depicted mice were nice and all birds were happy) yielded higher scores than similar sentences in which each adjective had to be associated with the proper character (e.g., Il cane giallo lava il maiale bianco, 'The yellow dog washes the white pig', where foils included a yellow dog washing a pink pig, and a brown dog washing a white pig). Many errors reflected recency effects, probably influenced by the fact that adjectives modifying the object appear at the end of the sentence in Italian. CONCLUSIONS & IMPLICATIONS: Differences between conditions were observed even when lexical content, syntactic structure and sentence length were controlled. This finding suggests the need for great care when assessing children's comprehension of sentences. The same syntactic structure and lexical content can vary in difficulty depending on the number and types of foils used in combination with the target picture.

Grammatical morphology deficits in Spanish-speaking children with specific language impairment.

The focus of this study was the use of grammatical morphology by Spanish-speaking preschoolers with specific language impairment (SU). Relative to both same-age peers and younger typically developing children with similar mean lengths of utterance (MLUs), the children with SU showed more limited use of several different grammatical morphemes. These limitations were most marked for noun-related morphemes such as adjective-agreement inflections and direct object clitics. Most errors on the part of children in all groups consisted of substitutions of a form that shared most but not all of the targets grammatical features (e.g., correct tense and number but incorrect person). Number errors usually involved singular forms used in plural contexts; person errors usually involved third person forms used in first person contexts. The pattern of limitations of the children with SU suggests that, for languages such as Spanish, additional factors might have to be considered in the search for clinical markers for this disorder. Implications for evaluation and treatment of language disorders in Spanish-speaking children are also discussed.

The phonology-morphology interface in the speech of Hebrew-speaking children with specific language impairment.

UNLABELLED: Phonological deficits are common in children with specific language impairment (SLI). However, the degree to which they constitute an area of extraordinary difficulty, and their contribution to the morphological deficits of these children are largely unknown. In this investigation, we studied a group of young children with SLI who were acquiring Hebrew, a language in which phonology and morphology are closely linked. The phonology of these children lagged behind that of same-age peers as well as younger normally developing children matched according to mean number of morphemes per utterance. Furthermore, the children with SLI were more likely to commit phonological errors that neutralized important morphological distinctions in their language. These findings have implications for both assessment and therapy. LEARNING OUTCOMES: As a result of this activity, the following learning outcomes will be achieved: The participant will be able to: (1) describe the differences in phonology between children with SLI and typically developing children; (2) describe the impact ofphonological disorders on the assessment of the morphological systems of children with SLI; and (3) explain the necessary modifications to a therapy program for children with a combination of morphological and phonological disorders.

Speed of processing in children with specific language impairment.

The aim of the present study was to investigate the speed with which children with specific language impairment (SLI) respond on a range of tasks. Seventy-seven third-grade children participated in 10 different tasks (involving a total of 41 conditions), including nonlinguistic and linguistic activities. Mean response times (RTs) of children with SLI (n = 29) increased as a function of mean RTs of children with normal language (NLD, n = 29) under each of three different regression models; children with SLI responded more slowly across all task conditions, and also when linguistic and nonlinguistic tasks were analyzed separately. Children with nonspecific language impairment (NLI) were also included (n = 19). The results were similar to those for children with SLI, but the degree of slowing was greater. The results of the group analyses support the hypothesis that speed of processing in children with SLI is generally slower than that of children with normal language. However, some children with SLI do not appear to show deficits of this type.

The influence of argument-structure complexity on the use of auxiliary verbs by children with SLI.

The purpose of the present study was to investigate the influence of argument-structure complexity on the omission of auxiliary be verbs in a group of children with specific language impairment (SLI). These children were compared to a group of younger, normally developing children matched for mean length of utterance (MLU) and a group of children matched for chronological age (CA). Using a story-completion task, the children (N = 30) were required to produce sentences of varying length and argument-structure complexity. The results of the study indicated that the children with SLI omitted more auxiliary forms than either the MLU or CA controls. In addition, both the children with SLI and the MLU controls were more likely to omit the auxiliary forms when attempting sentences with greater argument-structure complexity. These results suggest that argument-structure complexity may be a contributing factor to children's omissions of grammatical morphemes.

Tense and finiteness in the speech of children with specific language impairment acquiring Hebrew.

Verb morphology is often an area of extraordinary difficulty for children with specific language impairment (SLI). However, in Hebrew, this difficulty appears to be more circumscribed than in other languages. In a recent study by Dromi et al., the limitations exhibited by a group of Hebrew-speaking children with SLI were confined primarily to the use of agreement inflections within past tense. This difficulty was interpreted as being due to the fact that the agreement paradigm within past tense is rather complex (involving person, number, and gender, along with tense). This study explores another possibility--that these inflections were difficult because they required past tense in particular. Also determined was whether the children's frequent use of the morphologically simplest forms (such as past third person masculine singular) in place of the correct forms could be interpreted as their selection of a non-finite default form. A group of Hebrew-speaking children with SLI (age 4.2 to 6.1) participated, along with a group of age controls, and a group of younger normally developing children matched for mean length of utterance (MLU). The children listened to stories that were accompanied by pictures. During each story, the children completed the experimenter's incomplete sentences using appropriate verbs. To complete the sentences accurately, the children had to alter the tense or finiteness of the verb used by the experimenter in the preceding sentence. The results indicated that the children with SLI had more difficulty than both comparison groups in the production of basic present and past forms and infinitive forms of verbs that required use of one particular phonological template or 'binyan'. However, for the verbs requiring the remaining three phonological templates, the children with SLI were as capable as MLU controls in their command of past as well as present tense, and in their use of infinitive forms. It is concluded that tense and finiteness probably do not form the core of the problem faced by Hebrew-speaking children with SLI in the area of verb morphology.

Phonology and children with specific language impairment: status of structural constraints in two languages.

Two studies are reported in which the phonological characteristics of preschool-age children with specific language impairment (SLI) are compared with those seen in younger normally developing children matched for mean length of utterance and consonant inventory size. The productions of both English-speaking and Italian-speaking children with SLI were more likely to deviate from the adult standard than the productions of the younger control children. In Italian, the children with SLI had more difficulty than the younger controls in the use of non-final weak syllables; in English, the children with SLI were poorer than the younger controls in the use of non-final weak syllables, word-final consonants, and word-final consonant clusters. These are the same phonological details that are required for several grammatical inflections and many function words in the two languages. However, the children with SLI were also less consistent than their younger compatriots in using consonants in structurally simple words. These findings provide evidence for the view that for many preschool-age children with SLI, phonological problems go beyond those that might be predicted on the basis of the children's short utterances and limited consonant inventories.

The effects of inflectional variation on fast mapping of verbs in English and Spanish.

To use morphological cues for syntactic bootstrapping, children must recognize that inflectionally varying words (e.g., pushes, pushed) are instances of the same word. Children who are exposed to languages with richer inflectional morphologies than English, such as Spanish, encounter instances of inflectional variation more often. Thus they may learn to recognize inflectionally varying words as instances of the same word at an earlier age than do learners of English. English-and Spanish-learning 3-year olds were taught novel verbs in a fast mapping task under two conditions: no-inflectional variation in which inflections did not vary between exposure and testing (e.g., neps, neps) and inflectional variation in which inflections alternated between exposure and testing (e.g., neps, nepped). Children's scores were significantly higher in the no-variation condition than in the variation condition. There were no significant differences between the performance of the language groups. These findings suggest that even children acquiring languages with relatively rich verbal inflection paradigms may not be able to consistently parse stems and inflections to associate inflectionally varying forms.

Specific language impairment in Swedish: the status of verb morphology and word order.

Several competing proposals have been offered to explain the grammatical difficulties experienced by children with specific language impairment (SLI). In this study, the grammatical abilities of Swedish-speaking children with SLI were examined for the purpose of evaluating these proposals and offering new findings that might be used in the development of alternative accounts. A group of preschoolers with SLI showed lower percentages of use of present tense copula forms and regular past tense inflections than normally developing peers matched for age and younger normally developing children matched for mean length of utterance (MLU). Word order errors, too, were more frequent in the speech of the children with SLI. However, these children performed as well as MLU-matched children in the use of present tense inflections and irregular past forms. In addition, the majority of their sentences containing word order errors showed appropriate use of verb morphology. None of the competing accounts of SLI could accommodate all of the findings. In particular, these accounts--or new alternatives-must develop provisions to explain both the earlier acquisition of present tense inflections than past tense inflections and word order errors that seem unrelated to verb morphology.

Verb agreement morphology in Hebrew-speaking children with specific language impairment.

Earlier reports of verb morphology use by Hebrew-speaking children with specific language impairment (SLI) have suggested that these children mark agreement with the subject as accurately as younger control children matched according to mean length of utterance (MLU). This issue was examined in greater detail in the present study by including a wider range of agreement inflections from the present and past tense paradigms and employing verbs of different patterns (binyanim). It was hypothesized that children with SLI would be more limited than would MLU controls in their use of agreement inflections within past tense because the past tense agreement paradigm of Hebrew requires the simultaneous manipulation of three features-person, number, and gender. Differences between the groups were not expected for the use of agreement inflections within present tense, because only two features-number and gender-must be manipulated in the present tense paradigm. A group of preschool-age children with SLI was found to have more difficulty than did MLU controls in the use of most past tense agreement inflections. Within present tense, the two groups differed in their use of agreement inflections in only one pattern. For both groups, most errant productions differed from the target form by only one feature, usually person or tense. We found no feature that was consistently problematic for the children. The findings are discussed within a limited processing capacity framework.

Some differences between English plural noun inflections and third singular verb inflections in the input: the contributions of frequency, sentence position, and duration.

Grammatical inflections such as the English plural noun -s and third person singular verb -s are acquired at different points in time by young children. This finding is typically attributed to factors such as relative semantic salience or the distinction between lexical and functional categories. In this study input frequency, sentence position, and duration were examined as possible contributing factors. In both conversations with and stories aimed at young children, noun plural inflections were found to be more frequent than third singular verb inflections, especially in sentence-final position. Analysis of the speech of four mothers reading stories to their two-year-old children confirmed that duration differences also exist in the input. Because fricatives were lengthened in sentence-final position and plural nouns were much more likely to appear in these positions than were third singular verb forms, plural nouns were significantly longer than third singular inflections on average. The possible implications of these findings for language learnability theories and accounts of grammatical deficits in specific language impairment are discussed.

Grammatical morphology and the lexicon in children with specific language impairment.

We examined the use of grammatical morphology by preschool-age English-speaking children with specific language impairment (SLI) as a function of their lexical diversity. Relative to a group of normally developing (ND) preschoolers, these children's use of finite-verb morphology logged behind expectations based on the number of different verbs they used. Noun-related morphology fell below expectations based on overall lexical diversity. Differences between the ND children and children with SLI were also seen for the slope of the increases in finite-verb morphology as a function of lexical diversity, with shallower slopes in the SLI data. The findings of this study add to existing evidence suggesting that a measure of finite grammatical-morphology use has promise as a clinical marker of SLI in English.

Grammatical morphology and the role of weak syllables in the speech of Italian-speaking children with specific language impairment.

Italian-speaking children with specific language impairment (SLI) were compared to a group of younger control children in their use of auxiliary verbs, pronominal clitics, infinitives, present tense verb inflections, and articles. Differences favoring the control children were found for those morphemes that required the production of nonfinal weak syllables. On other grammatical morphemes, the two groups did not differ. A relationship was seen between the use of morphemes requiring nonfinal weak syllables and the use of nonfinal weak syllables that had no morpheme status. The findings are considered from the perspective of both prosodic production limitations and limitations in input processing.

Real-time inflectional processing by children with specific language impairment: effects of phonetic substance.

In this study, we examined the processing of low-phonetic-substance inflections (e.g., third-person-singular -s, past-tense -ed) versus a higher-phonetic-substance inflection (e.g., present-progressive -ing) by children with specific language impairment (SLI) in two types of receptive tasks. Twenty-one children with SLI (Age: 8 years;6 months), 21 chronological age matched (CA; Age: 8;7), and 21 receptive syntax matched (RS; Age: 6;8) children participated in a word-recognition reaction time (RT) task and an off-line task requiring grammaticality judgments. On the RT task, the children with SLI demonstrated RT sensitivity only to the presence of a higher-phonetic-substance inflection, unlike the CA and RS controls who displayed sensitivity to both higher-substance and low-substance inflections. On the grammaticality judgment task, the children with SLI performed more poorly than the CA controls only on sentences missing obligatory low-substance inflections (e.g., "Carl already jump over the fence"). The findings are discussed within the framework of the surface account, which predicts that children with SLI should have greater difficulty processing and making grammatical judgments about low-substance inflections compared to higher-substance inflections.

Specific language impairment and grammatical morphology: a discriminant function analysis.

Discriminant function analysis was employed to determine if grammatical morpheme production could be used to classify preschool-age children with specific language impairment (SLI) and children with typically developing language skills. Three variables were included in the discriminant analysis: a finite verb morpheme composite, a noun morpheme composite, and mean length of utterance in morphemes. The children with SLI and age-matched controls were discriminated with high levels of accuracy, though the three variables did not yield identical classifications. Across two samples of typically developing children and children with SLI, the verb morpheme composite showed sensitivity exceeding 85% and specificity of 100%. In light of these results and growing evidence that problems with finite verb morphology continue into the school years in children with SLI, the verb morpheme composite was considered to hold promise as a clinical marker for SLI.

Deficits in finite verb morphology: some assumptions in recent accounts of specific language impairment.

The grammatical morphology deficits common in children with specific language impairment (SLI) are characterized in some models as linguistic deficits. Such models must assume some mechanism for correct productions of finite verb forms. Three such assumptions were tested by analyzing speech samples from 18 children with SLI (aged 3 years 6 months to 6 years 9 months). Assumption 1, that nonfinite forms are used consistently until replaced by memorized finite forms, was tested by examining the distribution of verb types in present third-person singular and noun types in present third-person singular contractible copula contexts. Significantly more word types than expected were inflected inconsistently. Both Assumption 2, that finite and nonfinite verb forms are memorized but used indiscriminately, and Assumption 3, that affixation rules are applied indiscriminately, predict random use of finite forms. This prediction was not supported.

Three accounts of the grammatical morpheme difficulties of English-speaking children with specific language impairment.

Several hypotheses have been offered to explain the grammatical morpheme difficulties observed in the speech of children with specific language impairment. Three of the accounts that could be evaluated in English were the focus of this study: the extended optional infinitive account, the implicit rule deficit account, and the surface account. Preschoolers with specific language impairment, a group of age controls, and a group of younger children matched for mean length of utterance were evaluated in their use of several theory-relevant grammatical morphemes. The findings revealed advantages for both the surface and extended optional infinitive hypotheses. In contrast, a test of the predictions based on the implicit rule deficit account suggested that the children studied here were not experiencing a deficit of this type.

Grammatical deficits in Italian-speaking children with specific language impairment.

In earlier work, Italian-speaking children with specific language impairment (SLI) have been shown to exhibit a profile of grammatical morpheme difficulties that is quite different from the profile seen for English-speaking children with SLI. In the present study, this difference was confirmed using a wider range of grammatical morpheme types. A group of Italian-speaking children with SLI produced articles and third person plural verb inflections with lower percentages in obligatory contexts than a group of age controls and a group of younger controls matched for mean length of utterance (MLU). However, the children with SLI closely resembled the MLU controls in their production of noun plural inflections, third person copula forms, first person singular and plural verb inflections, and third person singular verb inflections. Errors on articles and copula forms were usually omissions whereas errors on verb inflections were usually productions of inappropriate finite inflections. Infinitives were seen in contexts requiring finite forms but they were not the dominant error type. Data from comprehension tasks raise the possibility that production factors were responsible for some of the differences seen. The findings of this study suggest that accounts of SLI are incomplete unless they assign a major role to the relative case of identifying and interpreting the relevant data in the ambient language. The implications of these findings for current accounts of SLI are discussed.

Lexical comprehension and grammatical deficits in children with specific language impairment.

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.