What is output? It is the way communication is delivered to the communication partner. It can be through speech or sounds, or through visual displays or printouts.
The ideal output for an individual AAC user will match not only his/her hearing and vision, but also the hearing and vision of communication partners as well as the context in which the communication takes place.
There are three basic categories of output types: auditory output (including synthesized speech) visual output, which includes gestures, manual signs, visual symbols as well as printed messages and electronic output, for example to connect to a telephone or computer. Follow these links to read more, but return here to read Clinical Considerations with Output below.
The importance of output for AAC strategies is sometimes underestimated. AAC manufacturers often incorporate only one output method in each device and many AAC specialists tend to select strategies with the access method in mind rather than the output. In addition, many clinicians forget that low tech or no tech AAC techniques have output that must be considered in electing to use a particular one.
When considering output options for an AAC aid, the following must be considered carefully:
1) The hearing and vision abilities of the AAC user, who must hear/see the output to verify the communication was correct;
2) The hearing and vision abilities of the communication partners, to ensure that all partners can receive the message that was delivered.
3) The visual memory of the communication partner. An alphabet board requires the partner to remember the sequence of letters as he/she watches the AAC user spell; A word board or symbol board requires the partners to remember the concepts as a longer message is being composed.
4) The language abilities of the communication partners. It would be a shame to provide voice output in English to a family that does not understand it. This is particularly problematic with synthesized speech, which is harder to understand than digitized speech. It is similarly inappropriate to provide a device with printed output to a child in a classroom of peers who cannot yet read.
5) The noise level and light levels of the communication environments, to ensure that the output is understandable.
6) The types of electronic devices that the user needs to control and the availability of funding and maintenance for those controls.
7) Any non-speech sounds that the user needs, including:
Notice in the list above that the output is governed more by the needs and capabilities of the communication partner and the environment than by the capabilities of the AAC user himself/herself. This is very important and it makes sense if you think about it. After all, speakers change the output of their communication depending on their partners. I speak more loudly to an uncle with a hearing loss; I speak English slowly to my mother-in-law in Japan, and I speak babytalk to my friend's infant. AAC users must also use different output to different partners in different circumstances, for example voice output to a group but visual output only for a private request. Unfortunately, there remains a tendency to let the output be determined by the user's diagnosis, as we discussed in an earlier lesson. Don't let yourself fall into that trap.
Interestingly, Galena (1989) found that the output affected the interaction style of the communication partner. When an AAC user had a low tech display, the adult partners increased their use of yes/no and multiple choice questions, presumably to control the interaction. When there was intelligible speech output or legible printed output, the partners asked fewer questions and controlled the conversation less. (Source: Glennen & DeCoste, 1997). This may be due to prejudices on the part of the partner who may have higher expectations of AAC users with devices than they do of people without devices.