Gf, they found, was associated with a broadly distributed network of brain regions primarily within the right hemisphere … This pattern of findings suggests that Gf reflects the ability to effectively integrate verbal, spatial, motor, and executive processes via a circumscribed set of cortical connections in the right hemisphere.
Lesion-study evidence demonstrates that fluid intelligence — the gold-standard measure of general cognitive capacity — is primarily a right-hemisphere function dependent on long white-matter integration tracts.
, The Matter with Things: Our Brains, Our Delusions, and the Unmaking of the World, 2021thesis