Individual differences in the shape bias in preschool children with specific language impairment and typical language development: theoretical and clinical implications.

We investigated whether preschool children with specific language impairment (SLI) exhibit the shape bias in word learning: the bias to generalize based on shape rather than size, color, or texture in an object naming context ('This is a wek; find another wek') but not in a non-naming similarity classification context ('See this? Which one goes with this one?'). Fifty-four preschool children (16 with SLI, 16 children with typical language [TL] in an equated control group, and 22 additional children with TL included in individual differences analyses but not group comparisons) completed a battery of linguistic and cognitive assessments and two experiments. In Experiment 1, children made generalization choices in object naming and similarity classification contexts on separate days, from options similar to a target object in shape, color, or texture. On average, TL children exhibited the shape bias in an object naming context, but children with SLI did not. In Experiment 2, we tested whether the failure to exhibit the shape bias might be linked to ability to detect systematicities in the visual domain. Experiment 2 supported this hypothesis, in that children with SLI failed to learn simple paired visual associations that were readily learned by children with TL. Analyses of individual differences in the two studies revealed that visual paired-associate learning predicted degree of shape bias in children with SLI and TL better than any other measure of nonverbal intelligence or standard assessments of language ability. We discuss theoretical and clinical implications.

Empirical Implications of Matching Children With Specific Language Impairment to Children With Typical Development on Nonverbal IQ.

This study determined the effect of matching children with specific language impairment (SLI) and their peers with typical development (TD) for nonverbal IQ on the IQ test scores of the resultant groups. Studies published between January 2000 and May 2012 reporting standard nonverbal IQ scores for SLI and age-matched TD controls were categorized into those that matched and did not match children with SLI and TD on nonverbal IQ. We then compared the nonverbal IQ scores across matching criterions within each diagnostic category. In studies that matched children on nonverbal IQ, children with SLI scored significantly higher on nonverbal IQ tests relative to children with SLI in studies that did not match on this criterion. Therefore, it appears that the nonverbal IQ performance of children with SLI is not comparable across studies that do and do not match samples on nonverbal IQ. This suggests that the practice of nonverbal IQ matching may have unintended consequences for the generalization of research findings to the broader SLI population.

Electrophysiology of Perception and Processing of Phonological Information as Indices of Toddlers' Language Performance.

Purpose: The toddler years are a critical period for language development and growth. We investigated how event-related potentials (ERPs) to repeated and novel nonwords are associated with clinical assessments of language in young children. In addition, nonword repetition (NWR) was used to measure phonological working memory to determine the unique and collective contribution of ERP measures of phonemic discrimination and NWR as predictors of language ability. Method: Forty children between the ages of 24-48 months participated in an ERP experiment to determine phonemic discrimination to repeated and novel nonwords in an old/new design. Participants also completed a NWR task to explore the contribution of phonological working memory in predicting language. Results: ERP analyses revealed that faster responses to novel stimuli correlated with higher language performance on clinical assessments of language. Regression analyses revealed that an earlier component was associated with lower level phonemic sensitivity, and a later component was indexing phonological working memory skills similar to NWR. Conclusion: Our findings suggest that passive ERP responses indexing phonological discrimination and phonological working memory are strongly related to behavioral measures of language.

Focused stimulation for a child with autism spectrum disorder: a treatment study.

This study explored the use of focused stimulation as an intervention technique for a three-year-old boy diagnosed with autism spectrum disorder (ASD). His parents were trained to use focused stimulation to facilitate comprehension of what is x doing question forms. Responses to question probes were collected at both pre- and post-treatment intervals. At the beginning of the study, the child did not respond correctly to any of the target questions. Following intervention, the child made significant gains towards the target goal, but little change towards a control goal used for comparison. These findings provide preliminary support for the usefulness of focused stimulation as an intervention strategy for at least some children with ASD.

Do children with Down syndrome have difficulty with argument structure?

The language transcripts of seven children with Down syndrome (DS) and seven typically developing children with comparable mean length of utterance (MLU) levels were examined for their use of verb argument structure. The children's production of subject arguments, direct object arguments, and inappropriate use of arguments (anomalies) were compared for each group. When compared across verb category, the results of this study revealed no significant group differences for the omission of subject arguments. However, when arguments for transitive verb productions were compared, the children with DS were more likely to omit subject arguments in comparison to direct object arguments. In addition, the normal control group was more likely to use anomalous argument patterns than the children with DS. These findings suggest that syntactic difficulties that are characteristic of children with DS may delay them in overcoming the optional subject (OS) phenomena (Ingham, 1992). A greater number of anomalous arguments used by the normal children suggests an inadequate knowledge of argument structure at this stage of language development. As a result of this activity, the participant will be able to describe the relationship between syntax and semantics as it applies to the knowledge of verbs in children with Down syndrome.

Phonological priming in adults who stutter.

UNLABELLED: The purpose of this study was to compare the speed of phonological encoding between adults who stutter (AWS) and adults who do not stutter (ANS). Fifteen male AWS and 15 age- and gender-matched ANS participated in the study. Speech onset latency was obtained for both groups and stuttering frequency was calculated for AWS during three phonological priming tasks: (1) heterogeneous, during which the participants' single-word verbal responses differed phonemically; (2) C-homogeneous, during which the participants' response words shared the initial consonant; and (3) CV-homogeneous, during which the participants' response words shared the initial consonant and vowel. Response words containing the same C and CV patterns in the two homogeneous conditions served as phonological primes for one another, while the response words in the heterogeneous condition did not. During each task, the participants produced a verbal response after being visually presented with a semantically related cue word, with cue-response pairs being learned beforehand. The data showed that AWS had significantly longer speech onset latency when compared to ANS in all priming conditions, priming had a facilitating effect on word retrieval for both groups, and there was no significant change in stuttering frequency across the conditions for AWS. This suggests that phonological encoding may play no role, or only a minor role, in stuttering. EDUCATIONAL OBJECTIVES: The reader will be able to: (1) describe previous research paradigms that have been used to assess phonological encoding in adults and children who stutter; (2) explain performance similarities and differences between adults who do and do not stutter during various phonological priming conditions; (3) compare the present findings to past research that examined the relationship between phonological encoding and stuttering.

The production of novel root compounds in children with specific language impairment.

This study examined ten children with specific language impairment (SLI), 16 normally developing children, and ten adults for the production of novel root compounds. The participants were asked to invent names for pictures of 24 pairs of contrasting, novel objects. For half of the pictures, the context supported a grammatical novel root compound, 16 contexts supported only an ungrammatical compound, and eight contexts supported a marginally grammatical compound. All participants used novel root compounds in grammatical contexts and relatively few compounds in ungrammatical contexts. The children with SLI used the information presented in the experimental probes less frequently than the normal controls. In addition, the children with SLI made more word-order errors in their production of novel compounds. However, they were as likely as their normal counterparts to resist the use of regular plural markers within compounds. The results of this study support a difficulty associated with processing linguistic information on the part of the children with SLI.

Lexical verb diversity in children with Down syndrome.

The language transcripts of seven children with Down syndrome and seven typically developing children matched for comparable MLU levels were compared for several measures of lexical diversity. These measures were percentage of utterances containing lexical verbs, number of verb tokens produced, a mean number of verbs per utterance (MVU), number of verb types used, and number of mental state verbs used. The results of this study indicated that the children with Down syndrome produced lexical verbs as frequently as their normally developing counterparts. In contrast, the children with Down syndrome were found to produce a larger variety of lexical verbs. An examination of a subset of verbs indicated that both groups of children produced an equal number of mental state verbs. These results support previous findings that when compared to syntactic development, children with Down syndrome show a relative area of strength in expressive vocabulary.

The omission of subject arguments in children with specific language impairment.

Ten children with specific language impairment (SLI) were compared to two groups of normally developing children for the production of grammatical subjects in sentences of varying length and argument structure complexity. The normal controls consisted of a group of younger children matched for mean length of utterance (MLU) and a group matched for chronological age. The participants were asked to produce sentences of varied argument structure complexity using a story completion task. The results indicated that both the children with SLI and the MLU controls omitted more subject arguments in the ditransitive sentences than in sentences with intransitive and ditransitive verbs. In addition, more children with SLI omitted subject arguments as linguistic complexity increased. This effect was not found for the normal age control children who never omitted subjects, regardless of increases in argument structure complexity. These results support the notion that grammatical errors in both children with SLI and their younger, normal counterparts may be due to problems with processing complex linguistic information rather than with limitations in linguistic knowledge.