Vowel distinctiveness as a concurrent predictor of expressive language function in autistic children.

Speech ability may limit spoken language development in some minimally verbal autistic children. In this study, we aimed to determine whether an acoustic measure of speech production, vowel distinctiveness, is concurrently related to expressive language (EL) for autistic children. Syllables containing the vowels [i] and [a] were recorded remotely from 27 autistic children (4;1-7;11) with a range of spoken language abilities. Vowel distinctiveness was calculated using automatic formant tracking software. Robust hierarchical regressions were conducted with receptive language (RL) and vowel distinctiveness as predictors of EL. Hierarchical regressions were also conducted within a High EL and a Low EL subgroup. Vowel distinctiveness accounted for 29% of the variance in EL for the entire group, RL for 38%. For the Low EL group, only vowel distinctiveness was significant, accounting for 38% of variance in EL. Conversely, in the High EL group, only RL was significant and accounted for 26% of variance in EL. Replicating previous results, speech production and RL significantly predicted concurrent EL in autistic children, with speech production being the sole significant predictor for the Low EL group and RL the sole significant predictor for the High EL group. Further work is needed to determine whether vowel distinctiveness longitudinally, as well as concurrently, predicts EL. Findings have important implications for the early identification of language impairment and in developing language interventions for autistic children.

Miniature Linguistic Systems for Individuals With Autism Spectrum Disorder: A Systematic Review and Meta-Analysis.

PURPOSE: Miniature linguistic systems (also known as matrix training) is a method of organizing learning targets to achieve generative learning or recombinative generalization. This systematic review is aimed at determining whether matrix training is effective for individuals with autism spectrum disorder (ASD) in terms of improving recombinative generalization for instruction-following, expressive language, play skills, and literacy skills. METHOD: A systematic review methodology was employed to limit bias in the various review stages. A multifaceted search was conducted. Potential primary studies were imported into Covidence, a systematic review software, and inclusion criteria were applied. Data were extracted regarding (a) participant characteristics, (b) matrix designs, (c) intervention methods, and (d) dependent variable. A quality appraisal using the What Works Clearinghouse (WWC) Single-Case Design Standards (Version 1.0, Pilot) was carried out. In addition to the visual analysis of the data, an effect size estimate, non-overlap of all pairs (NAP), was generated for each participant. Independent t tests and between-subjects analyses of variance were conducted to identify moderators of effectiveness. RESULTS: Twenty-six studies including 65 participants met criteria for inclusion. All included studies were single-case experimental designs. Eighteen studies received a rating of Meets Standards Without Reservations or Meets Standards With Reservations. The aggregated combined NAP scores for acquisition, recombinative generalization, and maintenance of a range of outcomes were in the high range. CONCLUSIONS: Findings suggested that matrix training is an effective teaching method for individuals with ASD for acquisition, recombinative generalization, and maintenance of a range of outcomes. Statistical analyses to identify moderators of effectiveness were insignificant. Based on the WWC Single-Case Design Standards matrix training meets criteria to be considered an evidence-based practice for individuals with ASD.

Feasibility and Preliminary Efficacy of Direct Instruction for Individuals With Autism Utilizing Speech-Generating Devices.

Direct instruction (DI) is an evidence-based approach to education that has been shown to be effective across a wide variety of student populations. Growing evidence suggests that DI may be an efficacious strategy for individuals with autism spectrum disorder (ASD). The current study aimed to evaluate the feasibility of using DI with students with ASD who utilize speech-generating devices (SGDs); 3 students with ASD whose primary mode of communication was an SGD were exposed to the Language for Learning Curriculum, Lessons 1-10. Student performance on pre- and posttests was measured, as well as student performance on exercises within each lesson. The average time to complete an exercise, number of repetitions, number of terminated sessions, and student affect were also evaluated. Results indicated that all 3 students could participate and complete exercises with some modifications to support SGD use. The students demonstrated improved performance, positive affect, and overall timely completion of exercises. Taken together, these findings suggest that DI may be feasible for some students with ASD who utilize SGDs.