Does Gestural Communication Influence Later Spoken Language Ability in Minimally Verbal Autistic Children?

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.