Input Distribution Influences Degree of Auxiliary Use by Children with Specific Language Impairment

Gradually increasing context-sensitivity shapes the development of children's verb marking: A corpus study

There is substantial evidence that children's apparent omission of grammatical morphemes in utterances such as "She play tennis" and "Mummy eating" is in fact errors of commission in which contextually licensed unmarked forms encountered in the input are reproduced in a context-blind fashion. So how do children stop making such errors? In this study, we test the assumption that children's ability to recover from error is related to their developing sensitivity to longer-range dependencies. We use a pre-registered corpus analysis to explore the predictive value of different cues with regards to children's verb-marking errors and observe a developmental pattern consistent with this account. We look at context-independent cues (the identity of the specific verb being used) and at the relative value of context-dependent cues (the identity of the specific subject+verb sequence being used). We find that the only consistent effect across a group of 2- to 3-year-olds and a group of 3- to 4-year-olds is the relative frequency of unmarked forms of specific subject+verb sequences being used. The relative frequency of unmarked forms of the verb alone is predictive only in the younger age group. This is consistent with an account in which children recover from making errors by becoming progressively more sensitive to context, at first the immediately preceding lexical contexts (e.g., the subject that precedes the verb) and eventually more distant grammatical markers (e.g., the fronted auxiliary that precedes the subject in questions). RESEARCH HIGHLIGHTS: We provide a corpus analysis investigating input effects on young children's verb-marking errors (e.g., Mummy go) across development (between 2 and 4 years of age). We find evidence that these apparent errors of omission are in fact input-driven errors of commission that persist into the third year of life. We compare the relative effect on error rates of context-independent (e.g., verb) and context-dependent (e.g., subject+verb sequence) cues across developmental time. Our findings support the proposal that children recover from making verb-marking errors by becoming progressively more sensitive to preceding context.

Sources of Misinterpretation in the Input and Their Implications for Language Intervention With English-Speaking Children

PURPOSE

In English and related languages, many preschool-age children with developmental language disorder (DLD) have difficulties using tense and agreement consistently. In this review article, we discuss two potential input-related sources of this difficulty and offer several possible strategies aimed at circumventing input obstacles.

METHOD

We review a series of studies from English, supplemented by evidence from computational modeling and studies of other languages. Collectively, the studies show that instances of failures to express tense and agreement in DLD resemble portions of larger sentences in everyday input in which tense and agreement marking is appropriately absent. Furthermore, experimental studies show that children's use of tense and agreement can be swayed by manipulating details in fully grammatical input sentences.

RESULTS

The available evidence points to two particular sources of input that may contribute to tense and agreement inconsistency. One source is the appearance of subject + nonfinite verb sequences that appear in auxiliary-fronted questions (e.g., Is [the girl running]? Does [the boy like popcorn]?) and as dependent clauses in more complex sentences (e.g., Help [her wash the dishes]; We saw [the frog hopping]). The other source is the frequent appearance of bare stems in the input, whether nonfinite (e.g., go in Make him go fast) or finite (e.g., go in I go, you go).

CONCLUSIONS

Although the likely sources of input are a natural part of the language that all children hear, procedures that alter the distribution of this input might be used in the early stages of intervention. Subsequent steps can incorporate more explicit comprehension and production techniques. A variety of suggestions are offered.

The Role of Spontaneous Repetitions During Treatment of Morphosyntactic Forms for Children With Developmental Language Disorder

Purpose Children with developmental language disorder sometimes spontaneously repeat clinician models of morphemes targeted for treatment. We examine how spontaneous repeating of clinician models in the form of recasts associates with improved child production of those emerging morphemes. Method Forty-seven preschool children with developmental language disorder participated in Enhanced Conversational Recast therapy and were monitored for spontaneous repetitions of morphemes modeled by the clinician through conversational recasting. We calculated proportion of correct and incorrect productions elicited during treatment and for generalization probes as well as treatment effect sizes. We then used odds ratios to determine the probability that a spontaneous repetition may precede treatment gains and calculated correlations of correct repetitions with correct in-treatment productions of targets and treatment effect sizes. Results Spontaneous repetitions were highly likely to happen just prior to meaningful treatment progress. Children with higher frequencies of correct spontaneous repetitions of morpheme targets also showed higher frequencies of correct productions of these forms during the course of treatment. Furthermore, children with an earlier onset of repetitions and higher frequencies of correct repetitions showed overall larger effect sizes at the end of treatment. Conclusions Children's use of correct forms in their repetitions may serve as a self-scaffold for mastering productions of the correct form via structural priming mechanisms. Tracking spontaneously repeated targets may be a useful milestone for identifying response to treatment.

Simulating the Acquisition of Verb Inflection in Typically Developing Children and Children With Developmental Language Disorder in English and Spanish

Children with developmental language disorder (DLD) have significant deficits in language ability that cannot be attributed to neurological damage, hearing impairment, or intellectual disability. The symptoms displayed by children with DLD differ across languages. In English, DLD is often marked by severe difficulties acquiring verb inflection. Such difficulties are less apparent in languages with rich verb morphology like Spanish and Italian. Here we show how these differential profiles can be understood in terms of an interaction between properties of the input language, and the child's ability to learn predictive relations between linguistic elements that are separated within a sentence. We apply a simple associative learning model to sequential English and Spanish stimuli and show how the model's ability to associate cues occurring earlier in time with later outcomes affects the acquisition of verb inflection in English more than in Spanish. We relate this to the high frequency of the English bare form (which acts as a default) and the English process of question formation, which means that (unlike in Spanish) bare forms frequently occur in third-person singular contexts. Finally, we hypothesize that the pro-drop nature of Spanish makes it easier to associate person and number cues with the verb inflection than in English. Since the factors that conspire to make English verb inflection particularly challenging for learners with weak sequential learning abilities are much reduced or absent in Spanish, this provides an explanation for why learning Spanish verb inflection is relatively unaffected in children with DLD.

Five overarching factors central to grammatical learning and treatment in children with developmental language disorder

BACKGROUND

During grammatical treatment of children with developmental language disorder (DLD), it is natural for therapists to focus on the grammatical details of the target language that give the children special difficulty. However, along with the language-specific features of the target (e.g., for English, add -s to verbs in present tense, third-person singular contexts), there are overarching factors that operate to render the children's learning task more, or less, challenging, depending on the particular target.

AIMS

To identify five such factors that can play a role in the grammatical learning of children with DLD. We use English as our example language and provide supporting evidence from a variety of other languages.

MAIN CONTRIBUTION

We show that the relative degree of English-speaking children's difficulty with particular grammatical details can be affected by the extent to which these details involve: (1) bare stems; (2) opportunities for grammatical case confusion; (3) prosodic challenges; (4) grammatical and lexical aspect; and (5) deviations from canonical word order.

CONCLUSIONS

During treatment, therapists will want to consider not only the English-specific features of grammatical targets but also how these more general factors can be taken into account to increase the children's success.

Individual Versus Small Group Treatment of Morphological Errors for Children With Developmental Language Disorder

Purpose This study examines the effects of enhanced conversational recast for treating morphological errors in preschoolers with developmental language disorder. The study assesses the effectiveness of this treatment in an individual or group ( n = 2) setting and the possible benefits of exposing a child to his or her partner's treatment target in addition to his or her own. Method Twenty children were assigned to either an individual ( n = 10) or group ( n = 10, 2 per group) condition. Each child received treatment for 1 morpheme (the target morpheme) for approximately 5 weeks. Children in the group condition had a different target from their treatment partner. Pretreatment and end treatment probes were used to compare correct usage of the target morpheme and a control morpheme. For children in the group condition, the correct usage of their treatment partner's target morpheme was also examined. Results Significant treatment effects occurred for both treatment conditions only for morphemes treated directly (target morpheme). There was no statistically significant difference between the treatment conditions at the end of treatment or at follow-up. Children receiving group treatment did not demonstrate significant gains in producing their partner's target despite hearing the target modeled during treatment. Conclusions This study provides the evidence base for enhanced conversational recast treatment in a small group setting, a treatment used frequently in school settings. Results indicate the importance of either attention to the recast or expressive practice (or both) to produce gains with this treatment. Supplemental Material https://doi.org/10.23641/asha.7859975.

Sensitivity to Morphosyntactic Information in Preschool Children With and Without Developmental Language Disorder: A Follow-Up Study

PURPOSE

This study tested children's sensitivity to tense/agreement information in fronted auxiliaries during online comprehension of questions (e.g., Are the nice little dogs running?). Data from children with developmental language disorder (DLD) were compared to previously published data from typically developing (TD) children matched according to sentence comprehension test scores.

METHOD

Fifteen 5-year-old children with DLD and fifteen 3-year-old TD children participated in a looking-while-listening task. Children viewed pairs of pictures, 1 with a single agent and 1 with multiple agents, accompanied by a sentence with a fronted auxiliary (is + single agent or are + two agents) or a control sentence. Proportion looking to the target was measured.

RESULTS

Children with DLD did not show anticipatory looking based on the number information contained in the auxiliary (is or are) as the younger TD children had. Both groups showed significant increases in looking to the target upon hearing the subject noun (e.g., dogs).

CONCLUSIONS

Despite the groups' similar sentence comprehension abilities and ability to accurately respond to the information provided by the subject noun, children with DLD did not show sensitivity to number information on the fronted auxiliary. This insensitivity is considered in light of these children's weaker command of tense/agreement forms in their speech. Specifically, we consider the possibility that failure to grasp the relation between the subject-verb sequence (e.g., dogs running) and preceding information (e.g., are) in questions in the input contributes to the protracted inconsistency in producing auxiliary forms in obligatory contexts by children with DLD.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.7283459.

Changes in English Past Tense Use by Bilingual School-Age Children With and Without Developmental Language Disorder

PURPOSE

The purpose of this study is to examine changes in English past tense accuracy and errors among Spanish-English bilingual children with typical development (TD) and developmental language disorder (DLD).

METHOD

Thirty-three children were tested before and after 1 year to examine changes in clinically relevant English past tense errors using an elicited production task. A mixed-model linear regression using age as a continuous variable revealed a robust effect for age. A 4-way repeated-measures analysis of variance was conducted with age (young, old) and language ability group (TD, DLD) as between-subjects variables, time (Time 1, Time 2) and verb type (regular, irregular, and novel verbs) as within-subject variables, and percent accuracy as the dependent variable. Subsequently, a 4-way repeated-measures analysis of variance was conducted to measure the overall distribution of verb errors across 2 time points.

RESULTS

Overall, children produced regular and novel verb past tense forms with higher accuracy than irregular past tense verbs in an elicitation task. Children with TD were more accurate than children with DLD. Younger children made more improvement than older children from Time 1 to Time 2, especially in the regular and novel verb conditions. Bare stem and overregularization were the most common errors across all groups. Errors consisting of stem + ing were more common in children with DLD than those with TD in the novel verb condition.

DISCUSSION

Contrary to an earlier report (Jacobson & Schwartz, 2005), the relative greater difficulty with regular and novel verbs was replaced by greater difficulty for irregular past tense, a pattern consistent with monolingual impairment. Age was a contributing factor, particularly for younger children with DLD who produced more stem + ing errors in the novel verb condition. For all children, and particularly for those with DLD, an extended period for irregular past tense learning was evident. The results support a usage-based theory of language acquisition and impairment.

The Changing View of Input in the Treatment of Children With Grammatical Deficits

PURPOSE

The purpose of this article is to present 3 approaches that emphasize the role that input plays in the treatment of grammatical deficits in children with language impairments.

METHOD

These approaches-input informativeness, competing sources of input, and high variability-were selected because they go beyond issues of token frequency and emphasize instead type frequency, relative frequency, and frequency at an abstract as well as a concrete level of grammar. Each of these approaches can be applied to the grammatical deficits seen in children with specific language impairment and can be readily used with well-established procedures, such as focused stimulation and recasting.

RESULTS

Each approach is supported by a body of laboratory research with children with typical language skills, and the feasibility of each has been tested in studies with a treatment design. Furthermore, the assumptions of the 3 approaches are largely compatible, permitting application of combinations of these approaches without violating any of their principles.

CONCLUSION

The positive findings from each of these approaches should serve as a basis for further clinical research.

Third person singular -s in typical development and specific language impairment: Input and neighbourhood density

The purpose of this study was to examine factors promoting the use of third person singular -s by 23 children with specific language impairment (SLI) and 21 children with typical development (TD). Relative proportions of third person singular -s forms in the input (input proportion) were calculated for 25 verbs based on data from an American English corpus of child-directed speech. Neighbourhood density values were also collected for these verbs. With previously collected probes of third person singular -s use for each of these verbs, we found with logistic regression that input proportion was positively associated with the likelihood of third person singular -s use for both groups. For neighbourhood density, we found that children with SLI were more likely to inflect sparse verbs than dense verbs; density was not significantly related to inflection use for TD children. We argue that as a result of their verbs' poorly encoded phonological representations, children with SLI were less able to inflect dense verbs than sparse verbs. We recommend that clinicians be aware of the effects of input proportion and neighbourhood density to ensure that assessments are representative and that treatment success is optimal.

Sensitivity to Morphosyntactic Information in 3-Year-Old Children With Typical Language Development: A Feasibility Study

PURPOSE

This study tested the feasibility of a method designed to assess children's sensitivity to tense/agreement information in fronted auxiliaries during online comprehension of questions (e.g., Are the nice little dogs running?). We expected that a group of children who were proficient in auxiliary use would show this sensitivity, indicating an awareness of the relation between the subject-verb sequence (e.g., dogs running) and preceding information (e.g., are). Failure to grasp this relation is proposed to play a role in the protracted inconsistency in auxiliary use in children with specific language impairment (SLI).

METHOD

Fifteen 3-year-old typically developing children who demonstrated proficiency in auxiliary use viewed pairs of pictures showing a single agent and multiple agents while hearing questions with or without an agreeing fronted auxiliary. Proportion looking to the target was measured.

RESULTS

Children showed anticipatory looking on the basis of the number information contained in the auxiliary (is or are).

CONCLUSIONS

The children tested in this study represent a group that frequently serves as a comparison for older children with SLI. Because the method successfully demonstrated their sensitivity to tense/agreement information in questions, future research that involves direct comparisons of these 2 groups is warranted.

A Clinical Evaluation of the Competing Sources of Input Hypothesis

PURPOSE

Our purpose was to test the competing sources of input (CSI) hypothesis by evaluating an intervention based on its principles. This hypothesis proposes that children's use of main verbs without tense is the result of their treating certain sentence types in the input (e.g., Wasshe laughing?) as models for declaratives (e.g., She laughing).

METHOD

Twenty preschoolers with specific language impairment were randomly assigned to receive either a CSI-based intervention or a more traditional intervention that lacked the novel CSI features. The auxiliary is and the third-person singular suffix -s were directly treated over a 16-week period. Past tense -ed was monitored as a control.

RESULTS

The CSI-based group exhibited greater improvements in use of is than did the traditional group (d = 1.31), providing strong support for the CSI hypothesis. There were no significant between-groups differences in the production of the third-person singular suffix -s or the control (-ed), however.

CONCLUSIONS

The group differences in the effects on the 2 treated morphemes may be due to differences in their distribution in interrogatives and declaratives (e.g., Ishe hiding/Heishiding vs. Doeshe hide/He hides). Refinements in the intervention could address this issue and lead to more general effects across morphemes.

Spontaneous Gesture Production and Lexical Abilities in Children With Specific Language Impairment in a Naming Task

PURPOSE

The purpose of the study was to investigate the role that cospeech gestures play in lexical production in preschool-age children with expressive specific language impairment (E-SLI).

METHOD

Fifteen preschoolers with E-SLI and 2 groups of typically developing (TD) children matched for chronological age (n = 15, CATD group) and for language abilities (n = 15, LATD group) completed a picture-naming task. The accuracy of the spoken answers (coded for types of correct and incorrect answers), the modality of expression (spoken and/or gestural), types of gestures, and semantic relationship between gestures and speech produced by children in the different groups were compared.

RESULTS

Children with SLI produced higher rates of phonological simplifications and unintelligible answers than CATD children, but lower rates of semantic errors than LATD children. They did not show a significant preference for spoken answers, as TD children did. Similarly to LATD children, they used gestures at higher rates than CATD, both deictic and representational, and both reinforcing the information conveyed in speech and adding correct information to co-occurring speech.

CONCLUSIONS

These findings support the hypotheses that children with SLI rely on gestures for scaffolding their speech and do not have a clear preference for the spoken modality, as TD children do, and have implications for educational and clinical practice.

Subordinate clause comprehension and tense/agreement inconsistency in children with specific language impairment

Several recent studies have suggested that the production errors of children with specific language impairment (SLI) such as The girl singing may be explained by a misinterpretation of grammatical adult input containing a similar structure (e.g., The boy hears the girl singing). Thirteen children with SLI and 13 younger typically developing children with comparable sentence comprehension test scores (TD-COMP) completed a comprehension task to assess their understanding of sentences involving a nonfinite subject-verb sequence in a subordinate clause such as The dad sees the boy running. TD-COMP children were more accurate on subordinate clause items than children with SLI despite similar performance on simple transitive (e.g., The horse sees the cow) and simple progressive (e.g., The cow is eating) items. However, no relationship was found between the SLI group's specific subordinate clause comprehension level and their specific level of auxiliary is production, casting some doubt on this type of structure as a source for inconsistent use of auxiliary is.

LEARNING OUTCOMES

The reader will learn that children with specific language impairment (SLI): (1) have difficulty understanding complex sentences that include nonfinite subject-verb sequences; (2) that this difficulty is apparent in comparison to younger typically developing peers who have similar scores not only on a sentence comprehension test, but also on simple sentences that correspond to the component parts of the complex sentences; and (3) that this weakness is concurrent with these children's inconsistent use of auxiliary is in production. Although novel verb studies show a clear connection between how children with SLI hear new verbs and how they use them, we do not yet have evidence that this connection is tied to a poor understanding of the input sentences that house the verbs.

Past Tense Production in Children With and Without Specific Language Impairment Across Germanic Languages: A Meta-Analysis

PURPOSE

This study examined the extent to which children with specific language impairment (SLI) across Germanic languages differ from their typically developing (TD) peers in the use of past tense morphology.

METHOD

A systematic literature search identified empirical studies examining regular and/or irregular past tense production by English and non-English Germanic-speaking children with SLI and their TD peers. Data from qualifying studies were extracted and converted to Hedges's g effect sizes.

RESULTS

Seventeen English and 8 non-English Germanic studies met inclusionary criteria. Comparing children with SLI and their TD age-matched (TDA) peers resulted in large combined effect sizes for English and non-English Germanic regular and irregular past tense production. Comparisons between children with SLI and their TD younger (TDY) peers also revealed large combined effect sizes for English and non-English Germanic regular past tense production. Effect sizes for studies comparing SLI and TDY irregular past tense production were large for non-English Germanic-speaking children and moderate for English-speaking children.

CONCLUSIONS

Results suggest that children with SLI across Germanic languages do indeed have more difficulty marking verbs for past tense than TDA and TDY peers. The findings suggest that the potential value of past tense production as a clinical marker of SLI may well extend beyond English.

Input sources of third person singular -s inconsistency in children with and without specific language impairment

We tested four predictions based on the assumption that optional infinitives can be attributed to properties of the input whereby children inappropriately extract non-finite subject-verb sequences (e.g., the girl run) from larger input utterances (e.g., Does the girl run? Let's watch the girl run). Thirty children with specific language impairment (SLI) and thirty typically developing children heard novel and familiar verbs that appeared exclusively either in utterances containing non-finite subject-verb sequences or in simple sentences with the verb inflected for third person singular -s. Subsequent testing showed strong input effects, especially for the SLI group. The results provide support for input-based factors as significant contributors not only to the optional infinitive period in typical development, but also to the especially protracted optional infinitive period seen in SLI.

Past tense -ed omissions by children with specific language impairment: The role of sonority and phonotactics

Children with Specific Language Impairment (SLI) frequently omit past tense -ed. Omission rates are subject to phonological context. Two phonological characteristics were manipulated; the sonority profile of the stem-final phoneme plus affix, and the phonotactic probability of the word-final phonemes (/i:pt/ in beeped). Seventeen children with SLI (mean age 6;7) and 21 language-matched children (mean age 4;8) repeated sentences containing regularly inflected verbs according to a 2 (sonority) by 2 (phonotactic legality) design. Affix omissions were analysed. There was a significant effect of sonority only, characterised by a difficulty with level-sonority clusters, and no interaction. Syllabic affixes, e.g. head-ed, were produced relatively accurately. It is argued that -ed omissions in SLI may reflect a low-level speech or articulation difficulty which surfaces in uniquely challenging clusters. This is not an alternative to morphosyntactic accounts; rather past tense omissions are best explained according to complexity in multiple domains; syntactic, morpho-syntactic and phonological.

Evaluation of three proposed markers for language impairment in English: a meta-analysis of diagnostic accuracy studies

PURPOSE

The goal of the study was to determine to what extent 3 proposed markers of language impairment (LI) in English (verb tense, nonword repetition, and sentence repetition) accurately distinguish affected and unaffected English-speaking individuals.

METHOD

Electronic databases were searched for diagnostic accuracy studies involving the 3 markers. Quality of relevant studies was described. Numbers of true and false positives and negatives were extracted and used to calculate likelihood ratios (LRs).

RESULTS

Thirteen studies met the selection criteria. The majority were based on clinically ascertained samples. Pooled LRs and 95% confidence intervals (CIs) for tense (LR+) and sentence repetition (LR+ and LR-) were suggestive of presence (LR+) or absence (LR-) of LI. Wide CIs around the value of inconsistency I2 index reduced reliability of pooled values for sentence repetition. High between-study heterogeneity precluded pooling of LR values for tense (LR-) and nonword repetition (LR+ and LR-).

CONCLUSION

The limited evidence available suggests that the proposed markers may be at best suggestive of LI in English. Future research may refine existing marker tasks to increase their accuracy and test the most promising tasks in unselected samples of participants with and without LI.

Children with a history of SLI show reduced sensitivity to audiovisual temporal asynchrony: an ERP study

PURPOSE

The authors examined whether school-age children with a history of specific language impairment (H-SLI), their peers with typical development (TD), and adults differ in sensitivity to audiovisual temporal asynchrony and whether such difference stems from the sensory encoding of audiovisual information.

METHOD

Fifteen H-SLI children, 15 TD children, and 15 adults judged whether a flashed explosion-shaped figure and a 2-kHz pure tone occurred simultaneously. The stimuli were presented at 0-, 100-, 200-, 300-, 400-, and 500-ms temporal offsets. This task was combined with EEG recordings.

RESULTS

H-SLI children were profoundly less sensitive to temporal separations between auditory and visual modalities compared with their TD peers. Those H-SLI children who performed better at simultaneity judgment also had higher language aptitude. TD children were less accurate than adults, revealing a remarkably prolonged developmental course of the audiovisual temporal discrimination. Analysis of early event-related potential components suggested that poor sensory encoding was not a key factor in H-SLI children's reduced sensitivity to audiovisual asynchrony.

CONCLUSIONS

Audiovisual temporal discrimination is impaired in H-SLI children and is still immature during mid-childhood in TD children. The present findings highlight the need for further evaluation of the role of atypical audiovisual processing in the development of SLI.

Children with specific language impairment and their contribution to the study of language development

Children with specific language impairment (SLI) are distinguishable from typically developing children primarily in the pace and course of their language development. For this reason, they are appropriate candidates for inclusion in any theory of language acquisition. In this paper, the areas of overlap between children with SLI and those developing in typical fashion are discussed, along with how the joint study of these two populations can enhance our understanding of the language development process. In particular, evidence from children with SLI can provide important information concerning the role of language typology in language development, the optimal ages for acquiring particular linguistic details, the robustness of the bilingual advantage for children, the role of input in children's acquisition of grammatical details, the unintended influence of processing demands during language assessment, the contributions of treatment designs to the study of typically developing children, and the study of individual differences in language development.

Decreased sensitivity to long-distance dependencies in children with a history of specific language impairment: electrophysiological evidence

PURPOSE

One possible source of tense and agreement limitations in children with specific language impairment (SLI) is a weakness in appreciating structural dependencies that occur in many sentences in the input. This possibility was tested in the present study.

METHOD

Children with a history of SLI (H-SLI; n = 12; M = 9;7 [years;months]) and typically developing same-age peers (TD; n = 12; M = 9;7) listened to and made grammaticality judgments about grammatical and ungrammatical sentences involving either a local agreement error (e.g., "Every night they talks on the phone") or a long-distance finiteness error (e.g., "He makes the quiet boy talks a little louder"). Electrophysiological (ERP) and behavioral (accuracy) measures were obtained.

RESULTS

Local agreement errors elicited the expected anterior negativity and P600 components in both groups of children. However, relative to the TD group, the P600 effect for the long-distance finiteness errors was delayed, reduced in amplitude, and shorter in duration for the H-SLI group. The children's grammaticality judgments were consistent with the ERP findings.

CONCLUSION

Children with H-SLI seem to be relatively insensitive to the finiteness constraints that matrix verbs place on subject-verb clauses that appear later in the sentence.

What Works in Therapy: Further Thoughts on Improving Clinical Practice for Children With Language Disorders

Purpose

In this response to Kamhi (2014), the author reviewed research about what does and does not help children with language impairment (LI) to learn grammatical features and considered how that research might inform clinical practice.

Method

The author reviewed studies about therapy dose (the number of learning episodes per session) and dose frequency (how learning episodes are spaced over time) and also reviewed studies about dose form, including input characteristics and therapy strategies.

Conclusion

Although the research is limited, it offers implications for how clinicians do therapy. Children with LI need many learning episodes clustered together within sessions but spread out over time across sessions. Input must be grammatical and consistent while providing varied exemplars of the target features. Learning episodes should actively engage children in producing utterances with the target form, but only after they have had the chance to hear some utterances with that feature. The author suggests a session plan that starts with a structured activity and then incorporates the target form into an embedded activity such as storytelling.

Maternal input to children with specific language impairment during shared book reading: is mothers' language in tune with their children's production?

BACKGROUND

The literature on input addressed to children with specific language impairment (SLI) has shown contrasting results on the role that parents assume during conversational interactions. Some studies have shown that parents compensate for the child's linguistic limitations. In contrast, other studies have indicated that mothers are able to adjust their communication in response to their children's language characteristics.

AIMS

To assess the 'closeness of fit' between maternal input and child language profiles in children with SLI during shared book reading. To achieve this aim, the individual linguistic features of a group of children with SLI and their mothers were compared with those of two typically developing (TD) groups and the 'distances' (i.e., the differences between the mother's and her child's linguistic indices) within each dyad were compared.

METHOD & PROCEDURES

Three groups of children with their mothers participated in the study: 14 children with expressive SLI, 14 language age-matched TD children (LA-matched group), and 14 chronological age-matched TD children (CA-matched group). Each mother-child dyad was videotaped during two weekly sessions of shared book reading, at home. All sessions were entirely transcribed. For each session, the following indices were then considered: whole-word phonological indices, grammatical categories and lexical indices for types and tokens, and the distance between the mother's and the child's linguistic indices within individual dyads.

OUTCOMES & RESULTS

Analysis of the differences between phonological, lexical and morphosyntactic characteristics of the mothers' and children's language indicated that both children with SLI and their mothers produced adjectives and adverbs with lower phonological complexity and with higher frequency of use compared with the CA-matched group, and nouns with lower frequency of use and higher age of acquisition compared with the LA-matched group. In addition, individual dyads within the SLI group displayed reduced distances between linguistic indices produced by the mother and child compared with dyads within the CA-matched group.

CONCLUSIONS & IMPLICATIONS

On the whole these findings suggest that mothers of children with SLI are able to tune their language to their children's linguistic limitations. These findings may contribute to improving early intervention programmes with children with SLI by focusing on the mother-child interaction during shared book reading.

Children's responses to telegraphic and grammatically complete prompts to imitate

PURPOSE

The purpose of this study was to determine whether children in the early stage of combining words are more likely to respond to imitation prompts that are telegraphic than to prompts that are grammatically complete and whether they produce obligatory grammatical morphemes more reliably in response to grammatically complete imitation prompts than to telegraphic prompts.

METHOD

Five children between 30 and 51 months of age with language delay participated in a single-case alternating treatment design with 14 sessions split between a grammatical and a telegraphic condition. Alternating orders of the 14 sessions were randomly assigned to each child. Children were given 15 prompts to imitate a semantic relation that was either grammatically complete or telegraphic.

RESULTS

No differences between conditions were found for the number of responses that contained a semantic relation. In contrast, 3 of the 5 children produced significantly more grammatical morphemes when presented with grammatically complete imitation prompts. Two children did not include a function word in either condition.

CONCLUSION

Providing a telegraphic prompt to imitate does not offer any advantage as an intervention technique. Children are just as likely to respond to a grammatically complete imitation prompt. Further, including function words encourages children who are developmentally ready to imitate them.