Childhood autism is difficult to distinguish from ADHD, which commonly co-occurs with it, and often difficult to diagnose as distinct from neurotypical development.
A quick video game session invites the child to imitate witnessed movements (controlling body configuration and transition perceptions). This turns out to be a remarkably reliable yet inexpensive diagnostic tool
To imitate another, one must internally generate the reference values that result in the externally observed behavioral outputs. Theory-blinded researchers, lacking ‘control theory glasses’, talked of ‘mirror cells’ in the CNS. This 2012 overview infers from eye-tracking in infants that the system develops before 12 months. A look at the developmental timing (verified many times by Plooij and other researchers) strongly suggests therapeutically relevant properties of autism and its early emergence.
6-9 months — relationships
9-11 months — the more complex relationships that we call categories
11-13 months — sequences
This correlation suggests that problems in the emergence of relationship-level control systems are at the root of later problems of autism in control of relationships, categories, and sequences as well as of the more overtly obvious impairment of ability to infer and ‘mirror’ the probable CVs and reference values of others by observing their motor outputs. I believe this suggests PCT-grounded early diagnosis and intervention with developmentally appropriate toys, etc. (as in The Wonder Weeks) supporting the emergence and control proficiency of systems at these levels of the control hierarchy.