True, but the equating of a brain with a city is largely specious, especially when trying to understand cognition. Yes a brain regulates many low level parasympathetic processes. But it's the decision making and memory systems that we most want to understand and replicate in silico. And the coordination of a city of mostly independent self-interested humans is a poor analogue for the biological bases for a coherent thought process, unless it's only the medulla or pons that we hope to model.