https://courses.lumenlearning.com/suny-ulster-ap1/chapter/spinal-cord A cross-sectional view shows that the spinal cord consists of gray matter made of cell bodies not covered in myelin and is surrounded by white matter made of axons covered in myelin. The description of the CNS is concentrated on the structures of the brain, but the spinal cord is another major organ of the system. Spinomesencephalic- ascends as part of the anterolateral system, it originates in the contralateral posterior horn, and terminates on multiple nuclei of the midbrain. Whereas the brain develops out of expansions of the neural tube into primary and then secondary vesicles, the spinal cord maintains the tube structure and is only specialized into certain regions. Summary. The gray matter is divided bilaterally into the dorsal (or posterior) horn, lateral horn, and ventral (or anterior) horn, each of which has unique functions. Some of the largest neurons of the spinal cord are the multipolar motor neurons in the anterior horn. Latin: cornu laterale medullae spinalis: Gray's: subject #185 753 The anterior horn of the spinal cord (also known as the anterior cornu) contains the cell bodies of motor neurons that affect the skeletal muscles. 2. an excrescence or projection shaped like the horn of an animal. The intermediolateral nucleus (IML) is found in the lateral horn of the spinal grey matter, which is part of Rexed lamina VII.The lateral horn exists only in certain segments of the spinal cord, viz the first thoracic to the second lumbar segments (the sympathetic outflow), and from the second to the fourth sacral segments (the parasympathetic outflow). Anatomically, the spinal cord is located within the spinal canal and extends from the bottom of the medulla (at the first cervical vertebra C1) to the conus medullaris (between L1 and L2). The cell bodies of these autonomic neurones are found in the lateral horn of the grey matter of the 1st thoracic to 2nd lumbar, and sacral segments 2-4 (see below). horn [horn] 1. a pointed projection such as the paired processes on the head of various animals, or other structure resembling them in shape. Top. In the dorsal horns (or posterior horns), many incoming sensory neurons synapse with interneurons, which then distribute information to other parts of the spinal cord and brain. Lateral horn; A spinal nerve with its anterior and posterior roots. The lateral horn, which is only found in the thoracic, upper lumbar, and sacral regions, is the central component of the sympathetic division of the autonomic nervous system. (Lateral column labeled at center right.) The Spinal Cord. The spinal cord is part of the central nervous system and coordinates motor, sensory, and reflex signals. The gray matter is the area of the spinal cord where many types of neurons synapse. Transverse section of the medulla spinalis in the mid-thoracic region. b.) The spinal cord is cylindrical, but it is wider in two areas- the cervical region (neck) and the lumbar region (lower back). (Lateral column labeled at top.) Blood is supplied to the spinal cord from the branches of the … Cervical and Lumbar Expansions of the Cord. The horn is further divided into segments (or columns) with to the dorsal horn situated to the back, the lateral horns placed to the sides, and the anterior horn located upfront.