To be honest, I think almost every neuroscientist has a murky idea of how the brain actually work. Consider that Deep Learning researchers can track every single computation an NN makes, yet we are still in the dark as to how exactly it works. Monitoring of what happens in the brain is extremely sparse, so its anybody’s guess as to what really happens.
To add to our ignorance, Deep Learning systems despite being astonishingly impressive, doesn’t have the kind of adaptability and quick learning as what is found in a brain.
We got a long way to go to understanding any of this.