Gary Strong

Speech Prostheses as a Metaphor for Verbal Short-term Memory

  • Gary W. Strong is Program Director for Interactive and Intermedia Technologies at the National Science Foundation, and Coordinator for the NSF on the National Science and Technology Council Committee on Computing, Information, and Communication.

  • Lap-top computers with touch-screens and speech synthesizers can be effective prostheses for people who are unable to speak. Observations of children who have never been able to speak due to physical disability indicate that their synthetically-produced speech is slower than real time speech due to the complexity of language selection from a touch-screen and that their sentences are initially "telegraphic" in grammatical style. Nevertheless, synthetic speech is better than no speech in nearly all situations. But, even more important, remarkable serendipitous benefits have been observed, benefits never anticipated, let alone predicted, by speech therapists.

  • Speech prostheses through dedicated programs on laptops are given some people who are born without the capacity to speak in order to enable them to converse and express their needs. However, observation shows that sometimes in the beginning an inordinate amount of time is spent by users playing with the device by themselves rather than employing it to communicate with others. However, long-term observation suggests that this activity is more than merely play. The way the device is employed resembles an outward expression of verbal short-term or working memory. The user selects words and constructions for himself or herself rather than for others in a way that suggests a rehearsal or recall instead of an intent to communicate with others. If this is true, the computer speech prosthesis may be a standing-in for a verbal short-term memory that was never developed because the users are congenitally without speech.

  • If it is true that such users do not have a verbal short-term memory, they will be unable to internally speak to themselves in a way that normal speakers take for granted. Without this ability, it is possible that the sense of self is impoverished in comparison to that of normal speakers. Therefore, initial behavior with a speech prosthesis may be that associated with discovering for the first time that one has something to say and that it can be sculpted before communication takes place. In this way, the device serves as not only a metaphor for the internal speech process, but as an actual external replacement for an important short-term working memory process that plays a role in the developing sense of self.


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