Vocal Modelling and Prompting

What is modelling?

Most AAC users will seldom witness other ACC users. Therefore, it might be helpful for you also to use the AAC within the interaction by modelling. You play an important role in shaping and reinforcing the AAC process, and conversation can be established through modelling and prompting.

Modelling refers to when a communication partner uses the AAC modality and demonstrates how to communicate with it. For example, if caregivers and educators utilise manual signing, it becomes the norm, and the learner is more likely to adopt the modality. Modelling works best when the individual identifies with the model - and some learners, such as adolescents, may also benefit from their peers' modelling. However, one important consideration when modelling is whether the learner can respond to a model as a prompt. This requires the learner to have imitation skills. Thus, before selecting this teaching strategy, evaluating the learner's ability to imitate is essential.

What is Vocal Modelling?

AAC-based modelling interventions contain two key components:

Modelling aided AAC modality as you speak;

Engaging in the context of naturalistic communication interaction.

In sum, you combine the physical demonstration of the use of the AAC with the relevant vocalisations to encourage the learner's development of vocal language. AAC modelling can occur naturally within the context of the learner's day, such as during a play routine or while reading a book. For example, whilst engaging in an activity, simultaneously model language using both the AAC device and speech. For example, if during a painting activity the learner is using blue paint, you might touch the symbols on their AAC modality for PAINT and BLUE, and say the associated words, or expand on the verbal model by stating, “you are painting with blue paint”. It might be helpful to prepare the AAC modality in advance to ensure it includes the vocabulary for upcoming activities.

What is Echoic Prompting?

Echoic prompting occurs when the learner repeats your vocalisations to learn through imitation and to produce the desired communication output.

You can provide verbal instruction combined with the relevant ACC response (e.g. say "book" whilst pointing to the picture of the book).

As the learner's understanding of language develops, you can begin to create sentences.

By speaking the vocal meaning of the AAC icons, you are allowing the AAC user to imitate your vocal model.

The goal is that eventually, the learner may independently vocalise the associated words whilst still engaging in functional communication via their AAC modality, and over time, their vocal communication without the assistance of AAC is strengthened.

Example:

Sara uses a Picture Exchange Communication System (PECS), which requires exchanging a picture of the preferred item with her communication partner to access the item. When she handed her sentence strip of "I want ball", her communication partner gave a vocal prompt of "ball". When Sara did not initially emit a vocal imitation after two further vocal prompts, her initial request with PECS was honoured, but she was only given the ball for a short period of time (differential reinforcement). After the ball was put away, her sentence strip was returned to the book. A second attempt occurred, whereby Sara delivered the same sentence strip to her communication partner, and when given the vocal prompt "ball", Sara made a partial vocalisation "ba", and her communication partner responded with the vocal model of "I want the ball!" and gave Sara access to the ball for a longer period of time. The process was repeated, and eventually, Sara provided the full vocalisation of "ball" for three consecutive trials.

There are two important aspects to keep in mind when using prompting strategies:

Identify a prompt that the person will respond to consistently;

Fade out the need for prompting over time so that the person learns to communicate without being prompted.

There are multiple ways to do this, including waiting longer before initiating a prompt (time delay is discussed in the next section), using less intrusive prompts (least-to-most prompting will be discussed later on), and using less and less of the prompt over time.

What is the benefit of incorporating vocal modelling into communication interventions?

Vocal modelling and echoic prompting are evidence-based strategies for aiding a learner's spoken language development. Pairing the spoken word with an aided symbol can improve comprehension and may enhance input-output asymmetries. It requires you to slow down to match the symbol with your speech and provides the added benefit of additional processing time for the learner. Implementing vocal modelling with an individual who uses a Speech-Generating Device means that the voice output serves as a third source of auditory input that helps the learner.

Incorporating vocal modelling into AAC interventions can make the communication experience more dynamic and effective, ultimately supporting better language development and social interaction for individuals who rely on these technologies.

Even when the learner is not yet imitating, vocal modelling can support their communicative competence by creating context for and encouraging language comprehension and communication.

References

Ganz, J. B., Hong, E. R., Leuthold, E., & Yllades, V. (2019). Naturalistic Augmentative and Alternative Communication Instruction for Practitioners

and Individuals With Autism. Intervention in School and Clinic, 55(1), 58-64. https://doi.org/10.1177/1053451219833012

Greenberg, A.L., Tomaino, M.E., & Charlop, M.H. (2014). Adapting the Picture Exchange Communication System to Elicit Vocalisations in Children

with Autism. Journal of Developmental and Physical Disabilities, 26, 35-51. https://doi.org/10.1007/s10882-013-9344-2.

Sennott, S. C., Light, J. C., & McNaughton, D. (2016). AAC Modeling Intervention Research Review. Research and Practice for Persons with Severe

Disabilities, 41(2), 101-115. https://doi.org/10.1177/1540796916638822

Sigafoos, J. (2021). Teaching Communication Skills to People with Intellectual and Developmental Disabilities. In Lang, R., Sturney, P. (Eds.),

Adaptive Behavior Strategies for Individuals with Intellectual and Developmental Disabilities. Autism and Child Psychopathology Series. Springer.

https://doi.org/10.1007/978-3-030-66441-1_4.

White, E.N., Cagliani, R.R., & Tyson, K.M. (2024). Effects on Speech Development With Modifications to Picture Exchange Communication System.

Focus on Autism and Other Developmental Disabilities, 39(1), 14-23. https://doi.org/10.1177/10883576231178266.