  Neuronal activity induces changes in blood flow by locally dilating vessels
in the brain microvasculature. How can the local dilation of a single vessel
increase flow-based metabolite supply, given that flows are globally coupled
within microvasculature? Solving the supply dynamics for rat brain
microvasculature, we find one parameter regime to dominate physiologically.
This regime allows for robust increase in supply independent of the position in
the network, which we explain analytically. We show that local coupling of
vessels promotes spatially correlated increased supply by dilation.
