Though it isn’t formally a diagnostic factor for autism, a delay in speech development is a common early sign of autism spectrum disorder. But why are speech development challenges common in ASD?
Though it’s not clear why speech delays are common in children on the autism spectrum, multiple factors are likely at work. One factor is differences in brain function and development in children with ASD. Challenges in socialization also likely have an impact on speech development, since language skills grow primarily through social interactions.
Sensory processing difficulties may also be a factor. Some children with ASD have difficulty processing multiple stimuli at once. For instance, what they see in a social situation may be difficult for them to synchronize with what they hear, contributing to impaired language development.