It's clear humans have several networks working together. Some Mathematicians report they 'see' the solution, these rely on a visual network *. Others report they prefer to do math symbolically (relying on the language network?).
Perhaps there are also multiple human paths to higher-level thought, with Keller (who lost her sight) using the language facility while others don't have to.
* Given Box 1 contents, the article authors seem unaware of the research on this? e.g.
https://www.youcubed.org/resource/visual-mathematics/
https://www.hilarispublisher.com/open-access/seeing-as-under...