Audio-visual speech perception training for a child with Autism Spectrum Disorders: A Case Study

Children with Autism Spectrum Disorders (ASD) often have difficulty acquiring normal language skills, a deficit that may stem from an inability to integrate audiovisual (AV) information. Audiovisual information is important for language development and enhances language skills. When added to speech, visible facial movements are known to enhance speech perception in noisy environments, removing the equivalent of 20 decibels of auditory background noise. As such, AV integration is critical to the acquisition of an adequate vocabulary in natural, noisy environments. Due to weaker lip reading skills than typically developing children, it has been demonstrated that children with ASD are less able to integrate matched AV speech in noisy environments. Despite these findings, few intervention studies have focused on addressing AV speech perception in children with ASD. The purpose of the current study is to teach lip reading in a changing criterion, multiple baseline design. During the baseline phase, a child with ASD was asked to identify auditory only, visual only, and bimodal consonant-vowel (CV) syllables (e.g. /bi/ and /di/). McGurk fusion stimuli were also tested in the pre-training and post-training periods. Following the initial baseline phase, the child was taught to read lips in increasingly progressively higher multitalker background noise in five stages, with a the criterion for moving to the next stage set at 100% accuracy. The expected outcome was that the child would demonstrate the ability read lips in background noise with greater accuracy compared to baseline. The participant showed increases in all modalities from pre to post-treatment. In addition, there was a consistent increase in correct responses over 4 of the 5 training sessions. Although the data shows general increase throughout the study, there was no change for the McGurk effect. The results of the study suggest that it is possible to train attention to the mouth to enhance perceptual performance using a changing criterion design. Findings are discussed with respect to previous studies of AV perception in ASD and future directions