Matthew Rispoli

This study piloted CHIPUTIL, an automated tool in CLAN for analysing sequential lexical overlap in parent–child conversations. In a sample of 44 dyads (child age M = 1;9), child spontaneous lexical overlap was positively associated with parent imitations and expansions, across the conversation and within sequential turns. Children were more than twice as likely to respond with lexical overlap when parents first produced an imitation or expansion. These findings offer insight into how lexical overlap may unfold in early conversations. We discuss implications of automated coding and future directions in exploring the role of lexical overlap in children’s language development.

Purpose: This tutorial is an introduction to first phase syntax (FPS; Ramchand, 2008 ). FPS provides a new, cross-linguistically motivated perspective on clause internal structure. A new sequence of syntactic development is proposed based on FPS with 4 levels of complexity: (0) verb particles and adjectives in the 1-word stage, (1) semantic relations of entity + location/attribution, (2) intransitive structures encoding change of location/state, and (3) transitive sentences with an internal argument that changes state/location and an external, causer argument. A novel prediction of this framework is that a Level 2 structure emerges earlier than a Level 3 structure. Method: Archival longitudinal data of 15 children (8 boys) were selected to test the proposed developmental sequence. The 15 children's data were drawn from the DeKalb corpora ( Rispoli, Hadley, & Holt, 2008 , 2009 ) and Champaign corpora ( Hadley, Rispoli, Holt, Fitzgerald, & Bahnsen, 2014 ), selected because their mean lengths of utterance did not exceed 2.54 at age 2;6 (years;months). One-hour language samples taken every 3 months from 1;9 to 2;6 were searched for Level 1–3 structures. The diversity of the internal argument was tracked across levels. Results: Average argument diversity shifted across levels over the period of 1;9–2;6. At 2;0, argument diversity was highest for Level 1; at 2;3, diversity was highest for Level 2; and at 2;6, it was highest for Level 3. Paired-samples t test revealed that, at 2;3, argument diversity in Level 2 was significantly higher than that in Level 3. Conclusion: This developmental application of FPS provides a theoretical framework for a developmentally ordered sequence of syntactic goals and treatment targets for children struggling with the acquisition of syntax.

Purpose The purpose of this letter is to clarify the psycholinguistic underpinnings of the tense marker total and tense agreement productivity score and to extend the discussion of when composite diversity and productivity measures are best used. Conclusion We encourage the use of composite diversity and productivity measures when assessing grammar early in development, but we discourage the use of composite accuracy measures until children demonstrate emergence of diverse tense/agreement morphemes across a sufficient number of low-frequency sentence frames.

Purpose This clinical focus article describes how to assess and when to target diverse, simple sentences as part of early language intervention. Method The theoretical foundations and clinical motivations for assessing sentence diversity based on unique combinations of subjects and verbs are explained, followed by a description of how to compute the measure. Sentence diversity is then related to familiar developmental measures of lexical diversity, utterance length, and grammatical complexity in a sample of 40 typically developing toddlers at 30 months of age. Descriptive and correlational analyses are used to demonstrate how sentences become more diverse as utterances also become longer and more complex. Conclusions The ability to produce simple sentences with diverse subject–verb combinations is proposed as a general developmental expectation for toddlers at 30 months of age. All 40 children produced at least 10 different subject–verb combinations in 30 min of parent–toddler conversation. Sentence diversity is also associated with familiar developmental measures. Recommendations are provided for using the measure of sentence diversity to inform treatment planning and monitor progress for young children with language disorders. Supplemental Material https://doi.org/10.23641/asha.5895976

Purpose: This article focuses on toddlers' revisions of the sentence subject and tests the hypothesis that subject diversity (i.e., the number of different subjects produced) increases the probability of subject revision.Method: One-hour language samples were collected from 61 children (32 girls) at 27 months. Spontaneously produced, active declarative sentences (ADSs) were analyzed for subject diversity and the presence of subject revision and repetition. The number of different words produced, mean length of utterance, tense/agreement productivity score, and the number of ADSs were also measured.Results: Regression analyses were performed with revision and repetition as the dependent variables. Subject diversity significantly predicted the probability of revision, whereas the number of ADSs predicted the probability of repetition.Conclusion: The results support the hypothesis that subject diversity increases the probability of subject revision. It is proposed that lexical diversity within specific syntactic positions is the primary mechanism whereby revision rates increase with grammatical development. The results underscore the need to differentiate repetition from revision in the classification of disfluencies.

Purpose: This follow-up study examined whether a parent intervention that increased the diversity of lexical noun phrase subjects in parent input and accelerated children's sentence diversity (Hadley et al., 2017) had indirect benefits on tense/agreement (T/A) morphemes in parent input and children's spontaneous speech. Method: Differences in input variables related to T/A marking were compared for parents who received toy talk instruction and a quasi-control group: input informativeness and full is declaratives. Language growth on tense agreement productivity (TAP) was modeled for 38 children from language samples obtained at 21, 24, 27, and 30 months. Parent input properties following instruction and children's growth in lexical diversity and sentence diversity were examined as predictors of TAP growth. Results: Instruction increased parent use of full is declaratives (η _p ² ≥ .25) but not input informativeness. Children's sentence diversity was also a significant time-varying predictor of TAP growth. Two input variables, lexical noun phrase subject diversity and full is declaratives, were also significant predictors, even after controlling for children's sentence diversity. Conclusions: These findings establish a link between children's sentence diversity and the development of T/A morphemes and provide evidence about characteristics of input that facilitate growth in this grammatical system.

Purpose The goals of this study were to quantify longitudinal expectations for verb lexicon growth and to determine whether verb lexicon measures were better predictors of later grammatical outcomes than noun lexicon measures. Method Longitudinal parent-report measures from the MacArthur-Bates Communicative Development Inventory (Fenson et al., 2007) from ages 21 to 30 months from an archival database were used to model growth in common noun and verb lexicon size for 45 typically developing toddlers. Communicative Development Inventory growth coefficients and 24-month measures of lexical diversity from spontaneous language samples were used to predict 30-month grammatical outcomes on the Index of Productive Syntax (Scarborough, 1990). Results Average verb growth was characterized by 50.57 verbs at 24 months, with linear growth of 8.29 verbs per month and deceleration overall. Children with small verb lexicons or slow linear growth at 24 months accelerated during this developmental period. Verb lexicon measures were better predictors of grammatical outcomes than noun lexicon measures, accounting for 47.8% of the variance in Index of Productive Syntax scores. Lexical verb diversity in spontaneous speech emerged as the single best predictor. Conclusion Measures of verb lexicon size and diversity should be included as part of early language assessment to guide clinical decision making with young children at risk for language impairment.

The contribution of parent input to children's subsequent expressive verb diversity was explored in twenty typically developing toddlers with small verb lexicons. Child developmental factors and parent input measures (i.e. verb quantity, verb diversity, and verb-related structural cues) at age 1;9 were examined as potential predictors of children's verb production in spontaneous language samples at age 2;3. Parent verb input diversity, rather than input quantity, was the primary input factor contributing to children's subsequent verb diversity. Regression analysis showed that verb diversity in parent input at age 1;9 accounted for 30% of the variance in children's verb production six months later, with children's total vocabulary size at age 1;9 accounting for an additional 16% of the variance. These findings demonstrate the relative contributions of developmental and input factors to individual differences in toddlers’ language development and establish the importance of input diversity to verb acquisition.