Spinal cord

The spinal cord extends caudally from the medulla oblongata through the vertebral canal and functions as the major conduit for neural signals between the brain and peripheral structures. It is organized into segmental levels, each giving rise to paired spinal nerves that innervate specific regions of the body. Within the spinal cord, grey matter (containing neuronal cell bodies) is centrally located and shaped like a butterfly, while white matter (composed of myelinated axons) surrounds it and carries sensory and motor pathways.

Anatomical features such as the central canal, median [dorsal] sulcus, and fissura mediana [ventralis] help define the spinal cord’s internal architecture, while the three protective meningeal layers—dura mater, arachnoid mater, and pia mater—support its structural integrity. Together, the brain and spinal cord coordinate reflexes, voluntary actions, and autonomic functions, forming the command center for all physiological processes.