Michael Halassa: Did John Nash Really Have Schizophrenia? is a good article on the genetics of psychosis. Previous research found that schizophrenia genes decreased IQ but increased educational attainment. Usually IQ and education are correlated, so this was surprising. The new research finds two components to schizophrenia genetic risk. The first component, shared with bipolar, increases educational attainment. The second component, not shared with bipolar, decreases IQ. They average out to the observed full-spectrum genetic signal of constant-to-increased educational attainment paired with constant-to-decreased IQ.

In 2021, I discussed tradeoff vs. failure models of psychiatric conditions, and said that most conditions were probably a mix of both. The new research seems to confirm this: the first genetic component of schizophrenia is a tradeoff: bad insofar as it gives you higher schizophrenia risk, good insofar as it gives you higher educational attainment. Most likely this has something to do with creativity or motivation. The second component is a failure: bad in every way, with no compensating advantage. Most likely this is detrimental mutations in genes for neurogenesis and synaptic pruning.

I mostly wasn't thinking about schizophrenia when I wrote about tradeoffs vs. failures, so I was surprised to see the theory so nicely reflected there. But in retrospect, this is common sense. All multifactorial problems should naturally be combinations of tradeoffs and failures.

https://www.astralcodexten.com/p/how-natural-tradeoff-and-failure