Neuroanatomy, Substantia Gelatinosa

Excerpt

The substantia gelatinosa of Rolando (SGR) is a grey matter structure of the dorsal spinal cord primarily involved in the transmission and modulation of pain, temperature, and touch. The structure is eponymously named after famed Italian anatomist Luigi Rolando, who first described the neuroanatomical region in the early 19th century. The gelatinous appearance of the SGR is due to the region’s abundant neuropil and relatively lower density of myelinated neurons.

The SGR spans the entire spinal cord extending rostrally into the medulla oblongata, where it becomes the spinal nucleus of the trigeminal nerve. Moreover, the structure receives and integrates inputs from peripheral sensory fibers (e.g., C, A-delta, and A-beta) of the dorsal root ganglia (DRG) along with descending pathways from the brain and brainstem and finally outputs to other regions of the dorsal horn and ascending pathways of the anterolateral system. The SGR serves a critical neurophysiological role in the gate control theory of pain.