The acquisition of language skills by autistic children: can parents do the job?

James et al. (1981) asked a simple question. Can parents teach their non-verbal autistic preschoolers to talk?

They trained six families in basic operant tricks: model words, wait, prompt, praise. Parents practiced at home every day for six months.

Kids were tested before, right after, and one year later. No control group—just the kids themselves.

Every child learned new words. Most doubled their spoken vocabulary.

One year later the gains were still there, but frozen. Without more teaching, kids did not add new words.

Bottom line: parent training works, but progress stalls if coaching stops.

Bradshaw et al. (2017) shows the idea still works today. They swapped pure operant drills for Pivotal Response Treatment and got the same language jump in toddlers.

Ouyang et al. (2024) looked at 32 newer trials and agrees: parent training helps, but only while parents keep high fidelity. The 1981 stall fits their pattern.

Higgins et al. (2021) repeated the setup with PRT and found the same freeze over the study period. Together these papers say: start with parents, stay with coaches.

You can give families a running start, not a finish line. Teach parents the first 20 words, then schedule monthly booster sessions. Use brief fidelity checks and refresh prompts before they fade. This keeps the curve climbing instead of flattening.