Cortical specificity in neurovascular coupling.

Despite mounting contrary evidence, the metabolic hypothesis is viewed as the predominant theory underlying neurovascular coupling, or the link between neural activity and cerebral blood flow. In a recent study, Huo et al. (Huo BX, Smith JB, Drew PJ. J Neurosci 34: 10975-10981, 2014) combined multimodal imaging and electrophysiology in experiments using awake, voluntarily moving mice to explore whether neurovascular coupling is uniform throughout the cortex. Whereas their results can be viewed as demonstrating that neural activity and blood flow are uncoupled in the frontal cortex during movement, the importance of this study is the elucidation that the metabolic hypothesis may not be the principle facilitator of neurovascular coupling in some regions of the cortex.