A communication system for the severely dysarthric speaker with an intact language system.

Two severely dysarthric speakers who had previously spelled entire messages on an alphabet board were taught a system in which they pointed to the first letter of each word as they spoke. Rate and intelligibility of speech produced with (aided) and without (unaided) the communication system were judged by observers who viewed videotaped samples. The rate of aided and unaided speech was markedly faster than spelling the entire message. Aided speech was slower but more intelligible than unaided speech. Further analysis revealed that intelligibility was influenced by at least two factors: (1) rate and (2) information provided by the identification of the first letter of each word. For one speaker both factors contributed to increased intelligibility, while for the other speaker only initial letter information appeared to influence intelligibility.