It was previously believed that children with severe language delays, who did not use phrases or speech by age 4, would not go on to develop fluent speech at all. But Marina Sarris of The Kennedy Krieger Institute says research is shedding new light on the subject. A study of over 500 nonverbal or minimally verbal autistic children showed that about 70% had achieved use of phrases or fluent speech by age 8.
The biggest factors in language acquisition seem to be non-verbal IQ and social behaviors like using facial expressions and sharing items. Repetitive interests, sensory issues, and stimming were not factors that influenced outcomes. They also said that children who developed speech after age 8 were hindered more by anxiety symptoms than cognitive abilities. You can find the full study here. Participants in this study had only one child in the family diagnosed with autism and no genetic disorders; more research is needed to know if these findings apply more broadly.
The biggest take-aways from the findings are the importance of continued work on joint attention and pro-social activities, as well as language development intervention. The most effective strategies are those that encourage communication while socializing. Despite previous beliefs, the window of opportunity may be bigger than we thought.
