Spinal cord

The spinal cord is part of the central nervous system with the brain. It carries neural signals from the brain and sensory information from the rest of the body, and is also responsible for certain reflexes. As it so vital to control of the body, it is enclosed by part of the vertebral column so that the vertebrae, or bones of the spine, protect it. The spinal cord is about 18 inches (46cm) long on average in human adults, and extends from the base of the brain down to the waist area. Spinal nerves branch off down the cord, connecting the motor neurons and other spinal tissue to other parts of the body.

The spinal cord can be affected by various diseases, such as: multiple sclerosis, which is an autoimmune disorder; spina bifida, in which the vertebral bones do not properly enclose it; and spinal muscular atrophy, in which the motor neurons deteriorate.