Thanks for sharing, I'll have to look into that book sometime. Also a real throwback to see Jonah Lehrer's name on a piece of scientific journalism.
Looks like in 2018 there's a few [0] interesting [1] papers [2] on the link between senescent glial cells and neurodegeneration, which I think would support a theory of glial cells playing some role in cognition. Seems to be a fairly active area of research.