Normal brain function requires continuous supply of oxygen and glucose in a strict manner.The close spatial and temporal relationship between neural activity and cerebral blood flow (CBF) is termed as neurovascular coupling,which is dependent or not dependent on astrocytes.The increase in flow evoked by brain activity is mediated by the concerted action of multiple mediators that originate from different cells and act at different levels of the cerebral vasculature.More studies are needed for further understanding the precise mechanisms underlying neurovascular coupling,especially the implications of astrocytes.