Abstract
PURPOSE: The current study examined the predictive role of gestures and gesture-speech combinations on later spoken language outcomes in minimally verbal (MV) autistic children enrolled in a blended naturalistic developmental/behavioral intervention (Joint Attention, Symbolic Play, Engagement, and Regulation [JASPER] + Enhanced Milieu Teaching [EMT]). METHOD: Participants were 50 MV autistic children (40 boys), ages 54-105 months (M = 75.54, SD = 16.45). MV was defined as producing fewer than 20 spontaneous, unique, and socially communicative words. Autism symptom severity (Autism Diagnostic Observation Schedule-Second Edition) and nonverbal cognitive skills (Leiter-R Brief IQ) were assessed at entry. A natural language sample (NLS), a 20-min examiner-child interaction with specified toys, was collected at entry (Week 1) and exit (Week 18) from JASPER + EMT intervention. The NLS was coded for gestures (deictic, conventional, and representational) and gesture-speech combinations (reinforcing, disambiguating, supplementary, other) at entry and spoken language outcomes: speech quantity (rate of speech utterances) and speech quality (number of different words [NDW] and mean length of utterance in words [MLUw]) at exit using European Distributed Corpora Project Linguistic Annotator and Systematic Analysis of Language Transcripts. RESULTS: Controlling for nonverbal IQ and autism symptom severity at entry, rate of gesture-speech combinations (but not gestures alone) at entry was a significant predictor of rate of speech utterances and MLUw at exit. The rate of supplementary gesture-speech combinations, in particular, significantly predicted rate of speech utterances and NDW at exit. CONCLUSION: These findings highlight the critical importance of gestural communication, particularly gesture-speech (supplementary) combinations in supporting spoken language development in MV autistic children.