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According to the weak central coherence (CC) account individuals with autism spectrum disorders (ASD) exhibit enhanced local processing and weak part-whole integration. CC was investigated in the verbal domain. Adolescents, recruited using a 2 (ASD status) by 2 (language impairment status) design, completed an aural forced choice comprehension task involving syntactically ambiguous sentences. Half the picture targets depicted the least plausible interpretation, resulting in longer RTs across groups. These were assumed to reflect local processing. There was no ASD by plausibility interaction and consequently little evidence for weak CC in the verbal domain when conceptualised as enhanced local processing. Furthermore, there was little evidence that the processing of syntactically ambiguous sentences differed as a function of ASD or language-impairment status.

Non-word repetition (NWR) was investigated in adolescents with typical development, Specific Language Impairment (SLI) and Autism Plus language Impairment (ALI) (n = 17, 13, 16, and mean age 14;4, 15;4, 14;8 respectively). The study evaluated the hypothesis that poor NWR performance in both groups indicates an overlapping language phenotype (Kjelgaard & Tager-Flusberg, 2001). Performance was investigated both quantitatively, e.g. overall error rates, and qualitatively, e.g. effect of length on repetition, proportion of errors affecting phonological structure, and proportion of consonant substitutions involving manner changes. Findings were consistent with previous research (Whitehouse, Barry, & Bishop, 2008) demonstrating a greater effect of length in the SLI group than the ALI group, which may be due to greater short-term memory limitations. In addition, an automated count of phoneme errors identified poorer performance in the SLI group than the ALI group. These findings indicate differences in the language profiles of individuals with SLI and ALI, but do not rule out a partial overlap. Errors affecting phonological structure were relatively frequent, accounting for around 40% of phonemic errors, but less frequent than straight Consonant-for-Consonant or vowel-for-vowel substitutions. It is proposed that these two different types of errors may reflect separate contributory mechanisms. Around 50% of consonant substitutions in the clinical groups involved manner changes, suggesting poor auditory-perceptual encoding. From a clinical perspective algorithms which automatically count phoneme errors may enhance sensitivity of NWR as a diagnostic marker of language impairment. Learning outcomes: Readers will be able to (1) describe and evaluate the hypothesis that there is a phenotypic overlap between SLI and Autism Spectrum Disorders, (2) describe differences in the NWR performance of adolescents with SLI and ALI, and discuss whether these differences support or refute the phenotypic overlap hypothesis, and (3) understand how computational algorithms such as the Levenshtein Distance may be used to analyse NWR data. (Contains 2 tables and 1 figure.)

Background: Recent studies have indicated that many children with autism spectrum disorders present with language difficulties that are similar to those of children with specific language impairments, leading some to argue for similar structural deficits in these two disorders. Aims: Repetition of sentences involving long-distance dependencies was used to investigate complex syntax in these groups. Methods & Procedures: Adolescents with specific language impairments (mean age = 15;3, n = 14) and autism spectrum disorders plus language impairment (autism plus language impairment; mean age = 14;8, n = 16) were recruited alongside typically developing adolescents (mean age = 14;4, n = 17). They were required to repeat sentences containing relative clauses that varied in syntactic complexity. Outcomes & Results: The adolescents with specific language impairments presented with greater syntactic difficulties than the adolescents with autism plus language impairment, as manifested by higher error rates on the more complex object relative clauses, and a greater tendency to make syntactic changes during repetition. Conclusions & Implications: Adolescents with specific language impairments may have more severe syntactic difficulties than adolescents with autism plus language impairment, possibly due to their short-term memory limitations. (Contains 4 tables and 2 figures.)

It has been argued that children with Specific Language Impairment (SLI) use language in a conservative manner. For example, they are reluctant to produce word-plus-frame combinations that they have not heard in the input. In addition, there is evidence to suggest that their utterances replicate lexical and syntactic material from the immediate language environment. Aims: This study investigated further the linguistic conservatism of children with SLI. It addressed the hypothesis that these children have difficulties using syntactic schemas in a verb-general manner. It employed a technique pioneered by Childers and Tomasello in 2001 that aims to develop verb-general representations through the presentation of appropriate exemplars. In addition, it tested the hypothesis that children with SLI present with input-dependent language use. Methods & Procedures: Twenty-four children with SLI (mean age 5 and 6 years) were matched to 23 typically developing children (mean age 3 and 5 years) on overall language abilities. The children experienced play sessions designed to simulate exemplar-based learning. Facilitative exemplars consisted of sentences that alternated between nouns and pronouns in the argument slots, e.g. Pooh 's churning the plate . See, he's churning it . The children were divided evenly into two groups. One group experienced facilitative exemplars, while the other group heard exemplars with no variation in the argument positions. The training effect was assessed with a procedure in which the children heard novel verbs in a non-transitive frame and were required to produce them in a transitive frame. In addition, the argument types of the children's responses (nouns versus pronouns) were analysed to investigate the issue of input dependence. Outcomes & Results: Few of the children produced novel verbs in the transitive. This result may indicate difficulties using the transitive, although a number of methodological difficulties may be responsible for finding. As hypothesized, the children with SLI demonstrated greater input dependence in terms of the kind of arguments they used in responses during the training sessions. Conclusions: Potential reasons for the low response rate of both groups during the testing stage are explored and a number of methodological adjustments proposed. It is argued that the greater input dependence of the children with SLI may reflect a tendency to reduce processing load within a limited capacity system. It is proposed that input dependence could be a fruitful new area for SLI research and an important issue in the design and delivery of therapy programmes. (Contains 3 tables, 1 figure, and 1 appendix.)

Purpose: This study explored the effect of frequency (number of presentations), and spacing (period between presentations) on verb learning in children with specific language impairment (SLI). Children learn words more efficiently when presentations are frequent and appropriately spaced, and this study investigated whether children with SLI likewise benefit. Given that these children demonstrate greater frequency dependence and rapid forgetting of recently acquired words, an investigation of frequency and spacing in this population is especially warranted. Method: Twenty-four children with SLI (mean age 5;6 [years;months]) and 24 language-matched control children (mean age 3;4) were taught novel verbs during play sessions. In a repeated measures design, 4 experimental conditions combined frequency (12 or 18 presentations) and spacing (all presentations in 1 session, or spread over 4 days). Comprehension and production probes were administered after the final session and 1 week later. Results: Although the children with SLI benefited significantly from frequent and widely spaced presentations, there were no significant effect in the control group. The language-impaired children showed rapid forgetting. Conclusions: The frequency and spacing of presentations crucially affect the verb learning of children with SLI. A training regimen characterized by appropriately spaced intervals and moderate repetition will optimally benefit lexical learning. (Contains 4 tables and 4 figures.)