How much energy does it take to think?

"The brain is not purely a cognition machine, but an object sculpted by evolution — and therefore constrained by the tight energy budget of a biological system.

Thinking may make you feel tired, then, not because you are out of energy, but because you have evolved to preserve resources.

This study of neural metabolism, when tied to research on the dynamics of the brain’s electrical firing, points to the competing evolutionary forces that explain the limitations, scope and efficiencies of our cognitive capabilities."

Read more here at Qanta Magazine