BublTalkDoes AAC delay speech?
Short answer: no. Across four decades of studies, researchers have not found that AAC reduces speech. Most found the opposite. But the honest version of that answer comes with limits, and I want to give you those too.
The fear
When a speech therapist first recommended AAC for my youngest, everything in me said no.
He'd had a handful of early words, and then they went away. He went quiet. And the idea of handing him a device that would talk for him felt like quietly giving up on him talking himself. I was scared that the moment he had an easier way to be understood, he'd stop trying to use his voice.
If that's where you are right now, I understand it completely. It's the most common worry parents have about AAC. It deserves a real answer, not reassurance.
So before we did anything, I went and read.
What the research found
The most-cited review
Millar, Light and Schlosser (2006, Journal of Speech, Language, and Hearing Research) pulled together the studies rigorous enough to draw conclusions from. In their best-evidence analysis of 27 cases, none showed a decrease in speech. Eleven percent showed no change, and 89 percent showed gains.
The study closest to our situation
Romski and colleagues (2010, same journal) ran a randomised controlled trial with 68 toddlers who had fewer than ten spoken words. Children in both AAC groups produced spoken target words. Children in the spoken-language-only group produced very few. The authors concluded that augmented communication "does not hinder, and actually aids, speech production abilities in young children with developmental delays." A 2021 follow-up analysis of the same data found no significant difference in speech sound errors, which rules out the obvious counter-worry.
Autism specifically
Schlosser and Wendt (2008, American Journal of Speech-Language Pathology) reviewed AAC studies in children with autism and found that AAC interventions "do not impede speech production," with most studies reporting increases.
And it has held up
White and colleagues replicated the finding in 2021 across 28 studies. A 2025 meta-analysis by Pope, Light and Laubscher found language outcomes were notably stronger when AAC was included in early intervention.
Four decades, different research groups, different methods, same direction. I could not find a single study pointing the other way, and I looked hard for one.
What the research does not say
This part matters as much, and it's where a lot of writing on this topic oversells.
"Does not impede" is not "accelerates." Most of this evidence shows an absence of harm. That's the answer to the fear, and it's genuinely reassuring. It is not proof that AAC will make your child talk.
The gains were modest. Schlosser and Wendt say so directly, and call for realistic expectations. Millar says the same. Nobody in this literature is promising a breakthrough.
The studies aren't a perfect match for a tablet app. The Millar review covered ages 2 to 60 and looked mostly at hand signs and non-electronic picture systems, with literature ending in 2003. The Romski trial used a speech-generating device delivered with 24 sessions of structured parent coaching from clinicians. That is not the same as a parent downloading an app and figuring it out alone. No study I found has tested a self-serve consumer app used without a therapist's support, and I'm not going to pretend otherwise about the one I built.
What the evidence supports is the direction: giving a young child a way to communicate does not take speech away from them.
What I'd tell another parent
The fear is reasonable. It's also, as far as forty years of research can tell us, not what happens.
What I'd add from our own life: the pressure in our house dropped. When a child has no way to tell you what they need, the day fills up with guessing, and guessing wrong, and the meltdown that follows. A way to be understood took some of that away. That's not a research finding, it's just ours.
Talk to your child's speech therapist. They know your child, and this article doesn't.
Common questions
Does AAC delay speech?
No. Across four decades of research, no study has found that AAC reduces speech production. In the best-evidence analysis of one widely cited 2006 review, none of 27 cases showed a decrease in speech, 11 percent showed no change, and 89 percent showed gains. Later reviews in 2008, 2021 and 2025 point in the same direction.
Will giving my toddler an AAC device stop them trying to talk?
The research does not support that fear. In a randomised controlled trial of 68 toddlers who had fewer than ten spoken words, children in both AAC groups produced spoken target words while children in the spoken-language-only group produced very few. The authors concluded that augmented communication does not hinder, and actually aids, speech production in young children with developmental delays.
Does AAC make children talk?
That is a stronger claim than the evidence supports. Most of this research shows an absence of harm rather than proof of benefit, and where researchers did find speech gains they described them as modest. AAC gives a child a way to be understood while speech develops. It is not a treatment that reliably produces speech.
Written by BublTalk's founder, a parent of a toddler who uses AAC. This article is not medical advice. It summarises published research so you can bring better questions to your child's speech-language pathologist. See our editorial policy.
References. Millar DC, Light JC, Schlosser RW (2006). Journal of Speech, Language, and Hearing Research 49(2):248-264 · Schlosser RW, Wendt O (2008). American Journal of Speech-Language Pathology 17(3):212-230 · Romski M et al. (2010). Journal of Speech, Language, and Hearing Research 53(2):350-364 · Walters C, Sevcik RA, Romski M (2021). American Journal of Speech-Language Pathology · White EN et al. (2021) · Pope L, Light J, Laubscher E (2025). Journal of Autism and Developmental Disorders 55(9):3078-3099