Infantile autism: a syndrome of multiple primary deficits?

Knapczyk (1989) wrote a theory paper. The author asked: what if autism is not one broken part, but many small breaks at once?

The paper looked at past brain and behavior data. It argued that no single deficit explains every child’s autism.

The paper said autism is a package of many small brain differences. These differences live side-by-side, not as one root cause.

Because of this, each child can show a unique mix of delays: language, play, mood, or sensory.

Later work kept testing the multi-deficit idea. Hudry et al. (2014) tracked early language alone and found its own separate path.

Reyes et al. (2019) showed temperament also moves on its own track in preschoolers. Matson et al. (2013) added that IQ level slightly shifts symptom strength, but never erases it.

Maddox et al. (2015) gave the idea a grown-up twist: half of cognitively able adults with ASD also meet rules for social anxiety disorder. Each study picks one slice—language, temperament, IQ, anxiety—and shows it can ride free of the others, just as Knapczyk (1989) guessed.

Stop hunting for one magic cause during assessment. Instead, run checklists for language, sensory, anxiety, and learning. Score each area on its own. When you write goals, pick the two weakest slices first. This keeps your treatment plan tight and honors the child’s true profile.