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DeepLeftAnalysis🔸's avatar

Regarding the association between autism and family achievement in the field of engineering, is this controlling for the fact that those who have higher SES might also have a higher average parental age? While it is true that autism is heritable, it may also be epigenetic. The genes for autism may lie dormant or latent in a population, and only become expressed or activated due to late parental age. When the genes for autism remain dormant, they may express themselves in positive ways, but when they become expressed due to reproductive damage from parental aging, they are deleterious.

Autism is not simply a heightened level of testosterone, but also an atrophy of social functioning. Otherwise, a person on steroids would become autistic. Autism could also be thought of as sickle cell anemia, where certain expressions of a gene are positive, but other expressions are deleterious.

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DC Reade's avatar

"What appears paradoxical given that autism is characterized by below-average IQ can be resolved under the hypothesis that autism involves enhanced, but imbalanced, components of intelligence. Crespi reviews several studies suggesting that increased local brain connectivity in autism is linked with specific enhanced abilities such as hyper-sensitivities and attention to detail but that comes at the cost of reduced long-range brain connectivity which could contribute to such imbalances by reducing general intelligence. Autism is indeed the only psychiatric condition characterized by notable rates of savant skills (Treffert, 2009), which account for their highly limited range of enhancements.

Another study consilient with IQ research found that autistic people had higher SD in IQ. They are are 12 times more likely to score within the intellectual disability range but also 1.5 times within the superior range (Billeiter & Froiland, 2022)."

The autism spectrum is only one trait cluster within a wider set of "non-neurotypical" features thus far found to appear in a significant fraction of the human population. Most of the research is very, very recent. Simply when considering the presentation of autism, beyond the simple interpretive estimates of low-functioning and high-functioning, verbal and nonverbal, there may be even more subsets to be identified. For example, the "idiot savant" manifestations of autism may have specific neurological pathways that strengthen those uncanny specialized abilities, or they may be enabled by the innate weakening of other brain capacities. (Or both. Or maybe it's a field effect. Etc.)

Some other forms of "non-neurotypical" variation include the attention deficit disorders; dyslexia; patterning and looping behaviors like OCD; variations in short-term memory recall capacity and long-term memory recording (possibly including idiosyncratic variation in regard to accuracy); eidetic imagery; extraordinary spatial modeling facility (Tesla, Beethoven); etc. Autism ("verbal", not low functioning) has already been shown to be correlated with a test-dependent variation in scores on IQ tests, often to a pronounced degree. Now results of that sort are showing up in the case of diagnosed ADD individuals (although the test-dependent correlation is quite different from that associated with verbal autistic individuals.) More and more attention is being given to examining the role of non-neurotypical variation as a confounding factor on IQ exam performance, and it's a subject that's only been given concerted research attention within the last 20 years or so.

What does this say about Spearman's "g" concept--that all intelligence abilities emerge from the same substrate, posited as a general foundation amenable to linear measurement- similar to, say, grip strength?

Except for means of measurement, of course, with grip strength determined by quite straightforward testing process to yield an unambiguously quantifiable result, whereas...let's just say that IQ tests don't rely on a similarly direct approach. A grip strength test and an IQ test are identical in only one respect: they yield a measurable score that's amenable to linear ranking.

Yet the result of an IQ test is somehow considered similarly precise and accurate--and considered much more significant than the result of a grip strength test, both in terms of its probative value both for the evaluation of individuals, and populations. This, despite the fact that the only result a written IQ examination can ever offer is a probability estimate, generated indirectly on the basis of a design intended to work for the purpose of providing an interpretive conclusion.

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