Optogenetic stimulation of striatal neurons and several afferents evoke robust negative fMRI responses in the striatum, while striatal electrophysiological recordings during the same stimulations show increases in neuronal activity. Pharmacological manipulations during D1MSN-induced negative striatal responses suggest responses are downstream of MSN activity, but not interneurons or local DA release. Fiber-photometry data from D2MSNs shows a similar pattern of neurovascular uncoupling/negative coupling. This negative fMRI response is also apparent in the human brain. Our results indicate that positive BOLD in the striatum is mediated through DA release, and that negative BOLD in the striatum is induced by local neuronal activations.