Fig. 24
(Figure reproduced from [4])
Diagram illustrating possible schemes for neurovascular coupling, i.e. regulation of blood flow changes associated with nerve activity. Two forms of control are shown, a simple feedback based on the signal to be regulated, e.g. pCO2, and b feedback plus feed-forward. The feed-forward element, signal2, in b, possibly from astrocytes, allows blood flow to increase with smaller changes in the primary quantity to be regulated, signal1