OverviewThe tissue called "gray matter" in the brain and spinal cord is also known as substantia grisea, and is made up of cell bodies. "White matter", or substantia alba, is composed of nerve fibers.
Update Date 2/3/2015
Updated by: Armit M. Shelat, DO, FACP, Attending Neurologist and Assistant Professor of Clinical Neurology, SUNY Stony Brook, School of Medicine, Stony Brook, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.