IQ is highly correlated with reaction times.[1] It's extremely difficult to explain that result if you assume IQ is purely cultural, rather than neurological.

IQ is highly correlated with reaction times.[1] It's extremely difficult to explain that result if you assume IQ is purely cultural, rather than neurological. [1]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5608941/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5608941/