A study published in Nature Communications reveals that basal forebrain cholinergic neurons regulate both cerebral blood flow and cerebrospinal fluid (CSF) movement. Using optogenetic activation and two-photon microscopy in mice, researchers demonstrated that stimulating these neurons induces rapid cortical microvessel dilation, enhancing blood supply. This neural control of the neurovascular unit and CSF flux broadens understanding of brain homeostasis and suggests new targets for neurodegenerative and injury therapies.