Does AAC stop children from learning to talk?

Some parents worry that a device will make their child less likely to try speaking. Researchers have studied how speech changes after AAC is introduced since the 1970s.

What did the research find?

In 2006, three researchers reviewed every study they could find on AAC and speech in people with developmental disabilities. They looked most closely at the six studies with the strongest designs, which covered 27 people. Not one of them lost speech after AAC was introduced. About 1 in 10 showed no change, and 89 percent gained speech. The authors noted that the gains were mostly modest.¹

Reviews of studies with autistic children had similar results. A 2008 review concluded that AAC does not get in the way of speech, and that most studies found speech went up somewhat, though not dramatically.² A 2021 update, covering research up to 2020, again found AAC was linked to more speech, though children's use of AAC usually grew faster than their speech.³

What about toddlers?

A randomized trial published in 2010 included 68 toddlers with developmental delays who had fewer than 10 spoken words. They were put into groups by chance. Parents in some groups were coached to use a speech-generating device with their child; parents in another group were coached to use speech only. The device groups learned more words and used spoken words as well as the device; the speech-only group produced very few spoken words. The researchers concluded that AAC "does not hinder, and actually aids" speech in young children with delays.⁴

And older children?

A 2014 randomized trial worked with 61 minimally verbal autistic children aged 5 to 8. Children whose therapy included a speech-generating device from the beginning made bigger gains in spontaneous spoken language, new words and comments than children taught with spoken words alone.⁵ A separate review found AAC also benefits autistic teenagers and adults.⁶

What does ASHA say?

ASHA, the American Speech-Language-Hearing Association, says that AAC use "may help improve natural speech when used in a multimodal approach" (meaning alongside speech, signs and gestures), and that "early AAC use can help develop speech and language." It also lists the belief that AAC delays language among the common misconceptions it hears from families.⁷

Why might AAC help speech?

The studies don't settle why. Two explanations come up often: a device says each word the same way every time, which gives a child a consistent model to copy, and being understood may take some pressure off speaking. The studies haven't shown whether either explanation is right.

Other worries parents raise

• "My child has to be ready first."ASHA says there are no prerequisites for AAC.⁷ A review of 114 studies found AAC helped about as much whatever a child's age, diagnosis, number of words or ability to imitate.⁸
• "AAC is a last resort."It is often used alongside speech therapy, for example with childhood apraxia of speech.⁹
• "A talking device is only for children without learning difficulties."High-tech AAC has shown benefits for people with intellectual and developmental disabilities,¹⁰ and ASHA says impaired cognition doesn't rule out communication.⁷
• "If we give the device, our child will figure it out."The strongest evidence is for adults using the device themselves as they talk, which is called modeling.¹¹ See examples of AAC modeling.

Limits of the research

Most of these studies include small numbers of children, and the speech gains they report are usually modest. They can't predict whether a particular child will talk.