Investigation of spontaneous– so-called‘resting-state'–activity of the central nervous system with functional magnetic resonance imaging (fMRI) holds great clinical potential to identify possible prognostic and diagnostic biomarkers for pain disorders and provides novel insights into the functional architecture of the central nervous system. Although previous resting-state studies in humans characterized functional networks of the brain and recently of the spinal cord, the resting-state networks of the entire central nervous system–delineating the interaction between the cord and the brain–have not been well characterized, possibly due to technical difficulties of corticospinal fMRI. Given the important role of ascending and descending pathways to understand disorders chronic pain disorders, here we characterize the resting-state functional connectivity networks along the whole neuroaxis in 29 healthy humans as a step prior to clinical studies. 31 brain slices and 12 cervical spinal cord slices from were acquired with a tailored fMRI sequence on a 3T system. Time courses of dorsal and ventral horns were used to map spinal cord's connection to the brain via a seed-based approach. Functional connectivity maps revealed that dorsal and ventral horn are significantly correlated with sensory and motor areas in the brain such as primary and somatosensory and motor cortices as well as with the thalamus. At the same time, we have observed that they somewhat distinct functional connectivity profiles in line with their functional segregation; frontal, occipital and insular cortices were more synchronized with ventral horn whereas caudate and thalamus appeared to be more synchronized with dorsal horn reflecting their functional division. NIH NINDS R01 NS109450.