The Brain's Supply Chain Challenges: Neurons Make Do with Limited Blood Flow.
Neuroscientists have discovered that blood flows in the brain like water down rivers, where it can, not where it is needed. This implies that the brain actually uses blood as it is supplied. The inability to multitask might have its origins in blood flow to the brain being supply-limited, not demand-based. The parts of the brain with the highest densities of neurons will be the first to be affected when there is a shortage of blood supply, just like the largest cities feel the pain of a drought before smaller ones. Taking care of the capillaries that keep neurons supplied with blood through a healthy diet and exercise may help maintain brain health in old age.