ABSTRACT
Roughly 0.5% of the population have such difficulties producing speech that is intelligible to others that they require some way of augmenting or replacing their natural speech. This chapter considers current clinical applications of speech synthesis, recognizing that high-tech communication devices represent only one component of rich multi-modal communication systems for individuals who use AAC. Speech sounds were generated using a special keyboard, essentially the basis of what is known as a text-to-speech procedure, now ubiquitous in speech synthesis. Much of the early work in speech synthesis focused on achieving a more human-sounding speech output. Since the emergence of DECTalk, both the technology underpinning speech synthesis as well as the applications in which it is now embedded have changed fundamentally. The divisions between pre-recorded digitized speech and text-to-speech synthesis have shifted. Clearly for any speech synthesis to be useful for functional communication, it must be intelligible to interaction partners.
