A more detailed brain scan would only be half of the answer. I am coming to the conclusion that there are two main affective elements - the nature of the channels / connections between the left and right brain, and an element of hypothalamic dysfunction affecting the endocrine system.
The range of possible combinations inherent in these differences would present as a "spectrum" of different potential effects sharing baseline similarities in a majority of cases, which can be affected (treated) in many different ways by different methods, from synthetic drugs to vitamins and proprioceptive exercises, with many different potential results depending on individual physical, social, mental and intellectual factors.
These can be further affected or exacerbated by external influences such as pollution, medication, diet / additives, chemical usage/abuse, trauma/stress (physical, emotional and social), and surgery on any part of the exocrine system.
Thus any "presented" or perceived Autistic "traits" or behaviours can be driven by a multitude of causative physical or hormonal effects or interactions within the organism, which is what the externally / perceptually -focused DSM erroneously concentrates on while ignoring the internal imbalances and deficiencies, in an attempt to categorise different"levels" or "types" of Autism.
Diagnostics and therapies need, IMO, a holistic approach beginning with bringing the body's various systems into balance and stabilising the physical organism, ideally prior to the application of psychoactive meds or cognitive therapies.
Note that I have said "affective" and not "causative" elements. I am not confident positing that there is a cause of Autism per se, as the increase in diagnoses could simply be down to greater awareness, greater availability of diagnostic practitioners, or greater population numbers. I do not feel that there is adequate data available for this to be accurately assessed.
In Potentia there could be an external physical cause, there could be a genetic/evolutionary cause, or there could be a genetic cause or even all of these.
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Aspie Score 173/200. NT score 43/200. AQ 37.
BAP: 108% Aloof. 117% Rigid. 112% Pragmatic.
Conformity sucks anyway.