Future success and achievement in life will be a function of communication ability. Therefore, AAC professionals have an awesome responsibility to do everything possible to optimize that potential. Cognitive science issues encompass a range of AAC considerations, from language representation methods to keyboard size and physical selection techniques. The most positive outcome of the AAC assessment is dependent upon familiarity with and proper consideration of these factors. The general assumption made here is that best success depends on the fastest and most automatic use of the AAC system.
Speed influences social communicative competence and pragmatics.
Speed is important in keeping the attention of the communication partner, maintaining long term relationships, and being generally productivity in educational and vocational pursuits. Automaticity is important to allow cognitive energy to be devoted to the content of communication rather than the process of generating it. These factors are not unrelated. Automaticity is one factor that contributes to speed. The human interface information transfer rate has historically been measured in terms of bits per second.