Phonological Treatment Options for Children with Expressive Language Impairment.

The vast majority of treatment efficacy research in the area of phonology focuses on issues relevant to children who have significant limitations in productive phonology but are "typically developing" in most other ways. The base of evidence to guide clinicians on planning intervention for children with phonological and cooccurring expressive language difficulties (PD + LI) is less well developed. Thus, the goal of this paper is to summarize the evidence on two treatment procedures designed to facilitate growth in phonological inventory for children who also require direct intervention to target other aspects of expressive language. We first review what is known about the delicate interaction between phonology and grammatical morphology. We focus the remainder of the summary on what is known about how to best address the more complex needs of children with PD + LI in intervention.

Neighborhood Density and Syntactic Class Effects on Spoken Word Recognition: Specific Language Impairment and Typical Development.

Purpose: The purpose of the current study was to determine the effect of neighborhood density and syntactic class on word recognition in children with specific language impairment (SLI) and typical development (TD). Method: Fifteen children with SLI (M age = 6;5 [years;months]) and 15 with TD (M age = 6;4) completed a forward gating task that presented consonant-vowel-consonant dense and sparse (neighborhood density) nouns and verbs (syntactic class). Results: On all dependent variables, the SLI group performed like the TD group. Recognition performance was highest for dense words and nouns. The majority of 1st nontarget responses shared the 1st phoneme with the target (i.e., was in the target's cohort). When considering the ranking of word types from easiest to most difficult, children showed equivalent recognition performance for dense verbs and sparse nouns, which were both easier to recognize than sparse verbs but more difficult than dense nouns. Conclusion: The current study yields new insight into how children access lexical-phonological information and syntactic class during the process of spoken word recognition. Given the identical pattern of results for the SLI and TD groups, we hypothesize that accessing lexical-phonological information may be a strength for children with SLI. We also discuss implications for using the forward gating paradigm as a measure of word recognition.

Grammatical treatment and specific language impairment: neighbourhood density & third person singular -s.

The purpose of this study was to test the effect of manipulating verb neighbourhood density in treatment targeting the third person singular lexical affix. Using a single-subject experimental design, six pre-schoolers with Specific Language Impairment (SLI) were randomly assigned to one of two conditions: (1) treatment with sparse verbs or (2) treatment with dense verbs in 12 sessions. The third person singular lexical affix was targeted for 12 sessions of treatment in both conditions. Treatment gain and generalization were measured as the dependent variables. Third person singular % correct change from pre-treatment to post-treatment was measured using sentence production tasks with comparisons across the two treatment conditions. Treatment gain and generalization were greater for children enrolled in the sparse condition. Preliminary clinical recommendations are made and theoretical implications are discussed relative to neighbourhood density effects on lexical activation and storage in children with SLI.

The interface between neighborhood density and optional infinitives: normal development and Specific Language Impairment.

The effect of neighborhood density on optional infinitives was evaluated for typically developing (TD) children and children with Specific Language Impairment (SLI). Forty children, twenty in each group, completed two production tasks that assessed third person singular production. Half of the sentences in each task presented a dense verb, and half presented a sparse verb. Children's third person singular accuracy was compared across dense and sparse verbs. Results showed that the TD group was significantly less likely to use optional infinitives with dense, rather than sparse verbs. In contrast, the distribution of optional infinitives for the SLI group was independent of verb neighborhood density. Follow-up analyses showed that the lack of neighborhood density effect for the SLI group could not be attributed to heterogeneous neighborhood density effects or floor effects. Results were interpreted within the Optional Infinitive/Extended Optional Infinitive accounts for typical language development and SLI for English-speaking children.

The influence of part-word phonotactic probability/neighborhood density on word learning by preschool children varying in expressive vocabulary.

The goal of this study was to examine the influence of part-word phonotactic probability/neighborhood density on word learning by preschool children with normal vocabularies that varied in size. Ninety-eight children (age 2 ; 11-6 ; 0) were taught consonant-vowel-consonant (CVC) nonwords orthogonally varying in the probability/density of the CV (i.e. body) and VC (i.e. rhyme). Learning was measured via picture naming. Children with the lowest expressive vocabulary scores showed no effect of either CV or VC probability/density, although floor effects could not be ruled out. In contrast, children with low or high expressive vocabulary scores demonstrated sensitivity to part-word probability/density with the nature of the effect varying by group. Children with the highest expressive vocabulary scores displayed yet a third pattern of part-word probability/density effects. Taken together, word learning by preschool children was influenced by part-word probability/density but the nature of this influence appeared to depend on the size of the lexicon.

Differentiating the effects of phonotactic probability and neighborhood density on vocabulary comprehension and production: a comparison of preschool children with versus without phonological delays.

PURPOSE: To differentiate the effect of phonotactic probability from that of neighborhood density on a vocabulary probe administered to preschool children with or without phonological delays. METHOD: Twenty preschool children with functional phonological delays and 34 preschool children with typical language development completed a 121-item vocabulary probe in both an expressive and receptive response format. Words on the vocabulary probe orthogonally varied on phonotactic probability and neighborhood density but were matched on age of acquisition, word frequency, word length, semantic set size, concreteness, familiarity, and imagability. RESULTS: Results show a Phonotactic Probability x Neighborhood Density interaction with variation across groups. Specifically, the optimal conditions for typically developing children were rare phonotactic probability with sparse neighborhoods and common phonotactic probability with dense neighborhoods. In contrast, only rare phonotactic probability with sparse neighborhoods was optimal for children with phonological delays. CONCLUSIONS: Rare sound sequences and sparse neighborhoods may facilitate triggering of word learning for typically developing children and children with phonological delays. In contrast, common sound sequences and dense neighborhoods may facilitate configuration and engagement for typically developing children but not for children with phonological delays because of their weaker phonological and/or lexical representations.

A Cross-Sectional Comparison of the Effects of Phonotactic Probability and Neighborhood Density on Word Learning by Preschool Children.

Two experiments examined the effects of phonotactic probability and neighborhood density on word learning by 3-, 4-, and 5-year-old children. Nonwords orthogonally varying in probability and density were taught with learning and retention measured via picture naming. Experiment 1 used a within-story probability/across-story density exposure context. Experiment 2 used an across-story probability/within-story density exposure context. Results showed that probability and density interacted to create optimal learning conditions. Specifically, rare/sparse sound sequences appeared to facilitate triggering of word learning. In contrast, the optimal convergence for lexical configuration and engagement was dependent on exposure context. In particular, common sound sequences and dense neighborhoods were optimal when density was manipulated across stories, whereas rare sound sequences and sparse neighborhoods were optimal when density was manipulated within a story. Taken together, children's phonological and lexical representations were hypothesized to be interdependent on one another resulting in a convergence of form characteristics for optimal word learning.

An online calculator to compute phonotactic probability and neighborhood density on the basis of child corpora of spoken American English.

An online calculator was developed (www.bncdnet.ku.edu/cml/info_ccc.vi) to compute phonotactic probability--the likelihood of occurrence of a sound sequence--and neighborhood density--the number of phonologically similar words--on the basis of child corpora of American English (Kolson, 1960; Moe, Hopkins, & Rush, 1982) and to compare its results to those of an adult calculator. Phonotactic probability and neighborhood density were computed for a set of 380 nouns (Fenson et al., 1993) using both the child and adult corpora. The child and adult raw values were significantly correlated. However, significant differences were detected. Specifically, child phonotactic probability was higher than adult phonotactic probability, especially for high-probability words, and child neighborhood density was lower than adult neighborhood density, especially for words with high-density neighborhoods. These differences were reduced or eliminated when relative measures (i.e., z scores) were used. Suggestions are offered regarding which values to use in future research.

Word learning by children with phonological delays: differentiating effects of phonotactic probability and neighborhood density.

UNLABELLED: This study examined the ability of 20 preschool children with functional phonological delays and 34 age- and vocabulary-matched typical children to learn words differing in phonotactic probability (i.e., the likelihood of occurrence of a sound sequence) and neighborhood density (i.e., the number of words that differ from a target by one phoneme). Children were exposed to nonwords paired with novel objects in a story and learning was measured by a picture naming task. Results showed that both groups created lexical representations for rare sound sequences from sparse neighborhoods. However, only children with typical development appeared to build on this initial lexical representation to create a full representation of the word (i.e., lexical-semantic connection and semantic representation). It was hypothesized that creating a lexical representation may be too resource demanding for children with phonological delays, leaving few resources available to create a lexical-semantic connection and/or a semantic representation. LEARNING OUTCOMES: The reader will be able to (1) define phonotactic probability; (2) define neighborhood density; (3) identify how these variables impact the word learning process in general; (4) identify potential areas of deficit in the word learning process for children with functional phonological delays.