Augmentative and Alternative Communication (AAC)

Is there much research on AAC? 

Yes, there is a great deal of research on AAC. Calculator & Black, (2009) reviewed 102 published articles and identified effective practices for teaching AAC to students with severe disabilities, including:

  • using naturalistic teaching,
  • using a system of least prompts,
  • training peers and teachers to use the devices,
  • teaching multiple modes of AAC,
  • teaching a single symbol for a variety of purposes, and
  • introducing the use of communication devices early in a child’s life.

Their literature review also suggests strong evidence for the use of AAC for students with severe disabilities. Numerous researchers have disproved the belief that persons with significant levels of cognitive disabilities could not benefit enough from communication devices to justify the cost (Light, Roberts, Dimarco, & Greiner, 1998; McNaughton, Light, & Arnold, 2002; Romski & Sevcik, 1997; Romski & Sevcik, 2000).

Will the use of AAC keep a child from learning to talk?

No, the use of AAC including voice output devices absolutely does not prevent the development of speech. Some of the best evidence for this comes from a thorough meta-analysis of the literature by Millar, Light, and Schlosser (2006). They reviewed hundreds of studies, eliminating those that were not well designed. They narrowed their focus down to 23 studies of high quality that involved 67 individuals from ages 2 to 60. These subjects included individuals with developmental disabilities, intellectual disabilities, mental retardation, or autism. They looked at speech production before, during, and after the introduction of AAC. They found unequivocally that AAC use did not slow or prevent the development of spoken language. In fact, speech production increased in 89% of the subjects. There was no evidence of decreases in speech in any subjects. For 11% of the subjects across all studies there was no change, but for 89% of those individuals provided with AAC, their speech production increased.

Will the use of AAC with voice output decrease other communicative attempts?

No, the use of AAC does not decrease other communicative behaviors. Schepis, Reid, Behrmann, & Sutton, (1998) investigated the potential for use of AAC to decrease communication behaviors such as gestures, vocalizations and words. They found no evidence that use of a voice output device decreased the frequency of gestures, vocalizations or word use. In fact, increases were seen for all children for one or more of the other communicative responses when they had access to AAC with voice output.

Will the use of AAC to slow down the development of speech?

No, AAC Intervention with young children with developmental delay actually facilitates the development of speech better than spoken language intervention alone. Romski, Sevcik, Adamson, Cheslock, Smith, Barker, & Bekeman (2010) studied 68 toddlers with developmental disabilities. Prior to the start of the study, they had fewer than 10 spoken words each. They randomly assigned them to three groups who were provided AAC for input (receptive language), AAC for output (expressive language), or spoken language intervention only. For the first group, the adult used symbols and pointed to them when speaking, for the second group the adult used hand over hand to help the child use a speech generating device. Their vocabulary use was checked after 18 sessions and 24 sessions. In both augmented interventions the children made modest, but significant gains. Children receiving spoken intervention only did not. The children who received AAC for output were more likely to produce spoken words.

What is the best way to teach a child to use AAC?

Key components to teaching a child to use AAC include:

  1. providing a robust vocabulary (don’t use a very restricted vocabulary);
  2. represented by symbols (type is not as important as previously thought); and,
  3. using a modeling-based intervention (presented with lots of modeling of aided language use by the adult).

Sennott, Light & McNaughton (2016) reviewed 10 studies, which included 31 participants in nine single subject design studies and one group design study and found the AAC modeling interventions led to meaningful linguistic gains across four areas including (a) pragmatics, indicated by increases in the number of communication turns taken; (b) semantics, shown by increases in receptive and expressive vocabulary; (c) syntax, marked by increased use of multi-symbol turns; and (d) morphology, as shown by increases in specific target morphology structures.

Using an AAC modeling-based intervention includes the adult repeatedly using the child’s AAC system to model how to initiate, respond, negate, continue, greet, wrap-up and all the other conversational turns we take. Research shows that this is the only way to show the child how they can do it.  By using their AAC system for real reasons, we show them what the symbols mean and how the whole process works. Remember that this may take a long time before the child starts doing it (we talk to infants for around 18 months before they start speaking), but an AAC modeling-based intervention is absolutely critical to develop communication skills (Sennott, Light & McNaughton, 2016).  It has been shown to increase receptive vocabulary – which totally makes sense (Dada & Alant, 2009) as well turn taking (Beck et al, 2009) and other communication skills.

Are there any resources about the use of AAC?

Yes, there are websites with resources about AAC:

 There is also a good review of the questions about AAC services that arise in Early Intervention. Search for: Cress & Marvin. (2003). Common Questions about AAC Services in Early Intervention.

What is the greatest challenge in teaching children to use AAC?

The greatest challenge is in training communication partners. Research by Binger et al., (2010); Kent-Walsh et al., (2010) Cumley & Beukelman, (1992); Light, Collier, & Parnes, (1985) shows that communication partners tend to:

  • Dominate interactions;
  • Ask predominantly yes/no questions;
  • Take the majority of conversational turns;
  • Provide few opportunities for client initiation or response;
  • Interrupt communicative attempts; and
  • Focus disproportionately on the technology

The ImPAACT Program (Kent-Walsh & Binger, 2013) is one intervention program that has been documented to yield positive results for clients using AAC. The Communication Partner instructional Protocol suggests that training of communication partners needs to:

  • Model effective AAC use;
  • Use an “expectant delay” (wait for the student to process, plan, and complete a response);
  • Ask “Wh—” questions (to prompt higher level expression)
  • Use verbal prompting (specify what to do);
  • Reinforce communicative attempts.

And finally, remember that the use of AAC, both low and high tech, is recognized as evidence based practice (EBP) (Morin, Ganz, Gregori, Foster, Gerow, Genc-Tosun, & Hong, 2018).