Cross-sectional studies of grammatical morphemes in autistic and mentally retarded children.

Allison et al. (1980) looked at how autistic and intellectually disabled children use little grammar words. These words are called functors. Examples are “the,” “is,” and “he.”

The team compared the two groups. They wanted to see who skipped these words and in what order.

Autistic children left out functors far more often. Their drop-out pattern did not match typical kids or kids with intellectual disability.

The missing words formed their own odd sequence. This hints that the problem is not just slow language growth. It looks autism-specific.

Eigsti et al. (2007) later saw the same odd gaps in verbal five-year-olds with autism. The 1980 pattern still held, just in younger kids.

Faught et al. (2021) pooled many later studies. They confirmed trouble with tricky pronouns like “himself.” The old 1980 data sit inside this bigger picture.

Webb et al. (1999) seems to clash. Three autistic students learned full sentences on a computer and used them in new places. Grammar improved, so the deficit may not be locked in stone. The 1980 view was static; the 1999 view says teaching can move the needle.

When you test language, do not stop at sentence length. Count how often the child drops “he,” “the,” or “is.” If the pattern looks quirky, plan explicit drills for those functors. Try computer lessons or error-correction scripts. The 1980 paper warns the gap is real, but the 1999 paper shows you can narrow it.