The 'go' and 'no-go' pathways, influenced by dopamine, are metabolically consuming and can lead to mental fatigue.

“Because, the next kind of level down of alertness, or autonomic arousal is clear, calm and focused where we have that kind of sweet spot between, our willingness to pursue action. We're in a mode of go, and it's not always physical action but it can be pursuing hard bouts of learning. But that our ability to suppress is also very good. And this is because, and I don't wanna get into too many details, because of the way that dopamine competes for these dopamine one receptors in the go pathway and dopamine two receptors in the no-go pathway.”