@reiver

IQ and Brain Size

[O]n the matter of brain size, it is now unquestioned that people who do best on formal intelligence tests also tend to have larger heavier brains, a once-mocked claim is now confirmed with in vivo MRI tests, with IQ and brain size correlations of between 0.3 to 0.4 (Deary 2001, Hunt 2011).

-- Garett Jones

from "National IQ and National Productivity: The Hive Mind Across Asia"

Quoted on Tue Aug 2nd, 2011