Synthetic Speech Perception in Individuals With and Without Disabilities.

Individuals with little or no functional speech frequently rely on non-speech communication systems to augment or replace natural speech. These systems include speech generating devices (SGDs), which provide synthetic speech upon activation. This paper comprises a summary of research conducted over the past 20 years on the perception of synthetic speech by nondisabled listeners and listeners with intellectual, language, and hearing impairments. A wide variety of perceptual studies have been conducted into how human listeners understand synthetic speech. Research has shown that perceptions of synthetic speech in individuals with intellectual and/or language impairments depend upon several general factors, including the acoustic-phonetic properties of the synthesizer, complexity of the perceptual task, and the experience of the listener. Additionally, individuals with intellectual and/or language impairments exhibit greater difficulties than nondisabled listeners with regard to processing synthetic speech signals that impose substantial cognitive demands.