If you're considering AAC for your child, someone has probably told you to wait. "Give speech a chance first." "If you give them a device, they'll never learn to talk." "It's a crutch." These are common AAC myths that don't hold up to scrutiny.
This concern comes from a good place. Parents want their children to speak. But the idea that AAC prevents or delays speech development is not supported by research. In fact, the evidence points in the opposite direction.
Let's look at what the studies actually found.
The Big Question
The fear boils down to this: if a child has an easy way to communicate without speaking, will they stop trying to talk?
It's intuitive. It makes sense on the surface. But it turns out that communication doesn't work like a zero-sum game. Having more ways to communicate doesn't reduce the drive to speak. It often increases it.
What the Research Says
Millar, Light, and Schlosser (2006)
This is one of the most cited studies in the AAC field. Millar, Light, and Schlosser conducted a systematic review of 23 studies involving 67 participants, looking at whether AAC interventions affected speech production.
Their findings:
- No participants showed a decrease in speech after starting AAC
- The vast majority of participants either maintained or increased their speech production
- The gains were observed across different types of AAC (sign language, picture systems, speech-generating devices) and across different disability groups
This wasn't a single study with a small sample. It was a review of the entire body of evidence available at the time, and the conclusion was clear: AAC does not inhibit speech.
Romski and Sevcik (2005)
Romski and Sevcik spent years studying children with developmental disabilities who used speech-generating devices. Their longitudinal research found that AAC use was associated with improvements in both comprehension and production of spoken language.
They proposed that AAC works as a language scaffold. The device gives children a reliable way to participate in conversations, which gives them more language exposure, more communication turns, and more reasons to engage. That increased engagement appears to support speech development rather than hinder it.
Schlosser and Wendt (2008)
Schlosser and Wendt conducted a meta-analysis examining the effects of AAC on speech production in children with autism. Their analysis included studies using various AAC modalities: sign language, picture exchange (PECS), and speech-generating devices.
The results were consistent with earlier findings. AAC either had no effect on speech or had a positive effect. There was no evidence that any form of AAC suppressed speech development in the populations studied.
More Recent Evidence
The research hasn't stopped. A systematic review by Logan, Iacono, and Trembath (2017) examined research on aided AAC to increase social-communication functions in children with autism spectrum disorder. Their analysis found consistent evidence of positive effects on communication, with no evidence of speech decline after AAC introduction.
The consistency of this finding across decades, research teams, disability groups, and AAC types is what makes it so reliable. This isn't one promising study. It's an entire field's worth of evidence all pointing in the same direction.
Why AAC Might Actually Help Speech
The research shows a pattern, but why does it work this way? Several explanations have been proposed:
Reduced pressure
When a child has a reliable way to communicate, the pressure to speak decreases. Paradoxically, this can make speech more likely. Children who are anxious about being understood may avoid speaking entirely. AAC removes that pressure and creates a safe context for attempting speech.
Increased language input
When families start AAC, they often become more intentional about communication in general. They model language more, narrate activities, and create more opportunities for interaction. The child ends up getting significantly more language input than before, which benefits speech development.
Multimodal reinforcement
When a child taps a symbol and the device says the word, they hear the word at the exact moment they're thinking about the concept. This pairing of motor action, visual symbol, and auditory output creates multiple pathways for learning. Some researchers believe this multimodal input strengthens the neural connections involved in speech production.
Communication success breeds motivation
Children who can communicate successfully are more motivated to keep communicating. AAC gives them early wins: they tap "want" and get what they asked for. That success builds confidence and motivation to communicate in all forms, including speech.
But What About My Child Specifically?
Research deals in patterns, and your child is an individual. That's a reasonable concern. Here are some honest nuances:
AAC is not guaranteed to increase speech. The research shows it doesn't decrease speech, and it often helps. But some children will remain primarily AAC users, and that's okay. The goal is communication, not speech specifically.
The type of AAC matters less than how it's used. Whether you use a high-tech app, picture cards, or sign language, the research shows similar patterns. What matters most is that communication partners (that's you) are actively modeling and using the system with the child.
Starting earlier is better than waiting. Several studies have found that children who begin AAC earlier show better outcomes than those who start later. The "wait and see" approach can mean missing critical periods for language development.
What to Tell People Who Push Back
You will encounter skepticism. Family members, acquaintances, sometimes even professionals who aren't current on the research. Here are the facts, stated simply:
- Decades of research across multiple AAC types and disability groups show no evidence that AAC reduces speech production
- Most children who start AAC maintain or increase their speech
- Waiting to introduce AAC does not improve speech outcomes and can delay overall language development
- The goal of AAC is communication. Speech may or may not follow, and either outcome is valid
You don't need to convince everyone. But you can feel confident that the evidence is on your side.
The Bottom Line
The question "Does AAC delay speech?" has been studied repeatedly for over 20 years. The answer is consistent: no. AAC does not delay, prevent, or reduce speech. In the majority of cases, it supports speech development.
If your child needs a way to communicate, don't wait. Give them the tools now.
Download SabiKo free and start today.
References
- Millar, D.C., Light, J.C., & Schlosser, R.W. (2006). The impact of augmentative and alternative communication intervention on the speech production of individuals with developmental disabilities: A research review. Journal of Speech, Language, and Hearing Research, 49(2), 248-264.
- Romski, M.A., & Sevcik, R.A. (2005). Augmentative communication and early intervention: Myths and realities. Infants & Young Children, 18(3), 174-185.
- Schlosser, R.W., & Wendt, O. (2008). Effects of augmentative and alternative communication intervention on speech production in children with autism: A systematic review. American Journal of Speech-Language Pathology, 17(3), 212-230.
- Logan, K., Iacono, T., & Trembath, D. (2017). A systematic review of research into aided AAC to increase social-communication functions in children with autism spectrum disorder. Augmentative and Alternative Communication, 33(1), 51-64.