Augmentative and Alternative Communication - Rate Enhancement Strategies

Rate Enhancement Strategies

Augmentative and alternative communication is typically much slower than speech, with users generally producing 8–10 words per minute. Rate enhancement strategies can increase the user's rate of output to around 12–15 words per minute, and as a result enhance the efficiency of communication. There are two main options for increasing the rate of communication: encoding and prediction.

Encoding is a technique permitting an AAC user to produce an entire word, sentence or phrase using only one or two activations of their AAC system. In numeric, alpha-numeric, and letter encoding (also known as abbreviation-expansion), words and sentences are coded as sequences of letters and numbers. For example, typing "HH" may retrieve "Hello, how are you?". In iconic encoding strategies, such as Semantic compaction, icons (picture symbols) are combined in a sequence to produce words or phrases.

Prediction is a rate enhancement strategy in which the device attempts to predict the letter, word or phrase being written by the user. The user can then select the correct prediction without needing to write the full word. Word prediction software may determine the words predicted based on their frequency in language, association with other words, past choices of the user, or grammatical suitability.