I believe that "Narrow Localizationism" is a scientific objection rather than political. Although it looks like some sort of political ideology, in fact it means the theory of narrow localization of the brain functions inside brain.
This seems plausible, since at the time it was known about localization of certain functions (Wernike's area, Broca's area Wernicke's area - Wikipedia, the free encyclopedia) while it was also known that higher cognitive function/thinking/ideation/conceptualization etc required broader capabiliities of whole telencephalon.