The patient's speech is, of course, an analogue input. The computer may then apply a number of filtering processes to the signal, to remove electrical 'noise' and to 'clean up' the input. Further processing of the sound information allows the computer to analyse the patient's speech patterns, and allows it to prepare the data for display. A simple 2-dimensional plot may be displayed, or more sophisticated presentation methods, such as interactive 'games' can be used. Further, stored information about the patient's previous speech patterns may be re-played to the patient via a sound card and speakers.
Games can be used to help speech therapy, especially in children with, for example, cleft palate .
The patient's own voice is recorded and analysed before radical surgery, and is subsequently used as a goal for that patient's therapy after surgery is complete. However, prices for these systems remain between 1500 and 20,000 and as such are still primarily used by speech scientists. However, much development is still necessary before this will be clinically useful. See what has to say on Speech Therapy.