One interpretation I’ve seen is that ~130 is about as high as a human brain can get while still using basically the same architecture as an IQ 100 brain. The further beyond that you get, the more you’re using significantly different systems. These differences may tend to be autism-related, such that the higher IQ comes at the expense of impairments.
My reading of the behavioral genetics literature is that high intelligence being driven by rare autism variants is looking unlikely. DeFries-Fulker extremes analyses like “Thinking positively: The genetics of high intelligence”, Shakeshaft et al 2015 aren’t consistent with the (relatively) high end being due to rare variants (but are consistent with the low end being due to rare variants) and current attempts to find rare variants enriched in the very high IQ with large effect sizes have turned up nothing: “A genome-wide analysis of putative functional and exonic variation associated with extremely high intelligence”, Spain et al 2015. There is also an autism heritability observed in the GCTAs/LD score regression using only common SNPs (>=1% population frequency), along with a positive autism/intelligence genetic correlation, which undermines that idea.
My speculation at this point is that Spearman’s law of diminishing returns is—based on all the genetic correlations with intelligence which have piled up and the current trends in brain imaging studies finding brain volume/thickness & global connectivity & white-matter integrity & connection speed to be the best predictors of intelligence—is due to intelligence reflecting a bottleneck between all the regions of the brain communicating to solve problems and that as the global communication becomes closer to optimal due to better health & development, individual specialized brain regions start to become the bottleneck to higher performance and shrinking the g factor.
My reading of the behavioral genetics literature is that high intelligence being driven by rare autism variants is looking unlikely.
I haven’t looked at this literature, but people with autism and very high IQs might be able to fake being neurotypical. As Steve Hsu told me, we don’t know if von Neumann had a normal personality because he certainly had the intelligence to fake being normal if he felt this suited his interests.
von Neumann was noted as being social and extraverted long before he began his lobbying and politicking, and was never described as a second Dirac, so I don’t think he was simply acting out of expediency. If high intelligence enabled faking extraversion & social skills, which are useful in almost all contexts*, we would see a noted personality correlation with intelligence and increasing with intelligence, which we don’t—extraversion is largely independent of IQ, it’s Openness in the Big Five which correlates. High-functioning autistic people are also not noted for easily acquiring psychopath-level skills in imitating & manipulating without feeling.
* see for example the correlation of increasing extraversion with increasing lifetime income in the Terman semi-high IQ sample
One interpretation I’ve seen is that ~130 is about as high as a human brain can get while still using basically the same architecture as an IQ 100 brain. The further beyond that you get, the more you’re using significantly different systems. These differences may tend to be autism-related, such that the higher IQ comes at the expense of impairments.
My reading of the behavioral genetics literature is that high intelligence being driven by rare autism variants is looking unlikely. DeFries-Fulker extremes analyses like “Thinking positively: The genetics of high intelligence”, Shakeshaft et al 2015 aren’t consistent with the (relatively) high end being due to rare variants (but are consistent with the low end being due to rare variants) and current attempts to find rare variants enriched in the very high IQ with large effect sizes have turned up nothing: “A genome-wide analysis of putative functional and exonic variation associated with extremely high intelligence”, Spain et al 2015. There is also an autism heritability observed in the GCTAs/LD score regression using only common SNPs (>=1% population frequency), along with a positive autism/intelligence genetic correlation, which undermines that idea.
My speculation at this point is that Spearman’s law of diminishing returns is—based on all the genetic correlations with intelligence which have piled up and the current trends in brain imaging studies finding brain volume/thickness & global connectivity & white-matter integrity & connection speed to be the best predictors of intelligence—is due to intelligence reflecting a bottleneck between all the regions of the brain communicating to solve problems and that as the global communication becomes closer to optimal due to better health & development, individual specialized brain regions start to become the bottleneck to higher performance and shrinking the g factor.
I haven’t looked at this literature, but people with autism and very high IQs might be able to fake being neurotypical. As Steve Hsu told me, we don’t know if von Neumann had a normal personality because he certainly had the intelligence to fake being normal if he felt this suited his interests.
von Neumann was noted as being social and extraverted long before he began his lobbying and politicking, and was never described as a second Dirac, so I don’t think he was simply acting out of expediency. If high intelligence enabled faking extraversion & social skills, which are useful in almost all contexts*, we would see a noted personality correlation with intelligence and increasing with intelligence, which we don’t—extraversion is largely independent of IQ, it’s Openness in the Big Five which correlates. High-functioning autistic people are also not noted for easily acquiring psychopath-level skills in imitating & manipulating without feeling.
* see for example the correlation of increasing extraversion with increasing lifetime income in the Terman semi-high IQ sample
What definition of “autism” would you use in this case?