Coupling of Function, Metabolism, and Blood Flow in the Brain

Abstract

Functional activity, metabolism, and blood flow in the brain, although locally heterogeneous, are tightly coupled. Blood flow is adjusted to local activity in two ways: 1) short-term, dynamic coupling mediated by local vasoactive factors that ensure second-to-second regulation;and 2) long-term, static coupling apparently mediated by changes in capillary density. Recognizing these two mechanisms permits one to distinguish apparent from real uncoupling.