Effect of auditory-motor mapping training and speech repetition training on consonant and vowel accuracy in minimally verbal children with autism spectrum disorder

Abstract

Various therapies exist for teaching first words to minimally verbal (MV) children with autism spectrum disorder (ASD). Previous outcome measures have focused on number of words imitated or produced spontaneously, or on communication rate. No studies thus far have examined phonetic accuracy in MV ASD as a result of therapy, yet understanding whether therapy improves articulation in MV ASD is important for understanding how speech is affected in ASD and how best to treat these children. In this preliminary study of 30 children with MV ASD, we report on perceptual analysis of their speech after 25 sessions of one of two therapies, employing bisyllabic stimuli with a variety of consonant types. Twenty-three children received Auditory Motor Mapping Training (AMMT), where stimuli are intoned at approximately one syllable per second. Seven children, matched on age and cognition to 7 AMMT participants, received Speech Repetition Training (SRT), where non-intoned stimuli are presented at a normal speech rate. ANOVAs indicated that AMMT resulted in greater gains in consonant production accuracy than SRT. Both therapies produced equally significant improvement in vowel accuracy. Additional, ongoing analyses concern participants’ accuracy for different consonant types, investigating whether accuracy is greater for earlier-appearing than later-appearing consonant types.