Definition:
The spinal cord is a long, tubular bundle of nervous tissue that extends from the base of the brainstem down to the lower back. It is a crucial part of the central nervous system (CNS) and acts as a communication pathway between the brain and the rest of the body.
Structure:
The spinal cord is cylindrical in shape and roughly 18 inches long in adults. It is composed of a series of connected nerve cells, or neurons, which are bundled together into tracts. These tracts are organized in a way that reflects the functions and sensory information they carry.
Location:
The spinal cord is protected within the spinal canal, which is formed by the vertebrae of the spine. It runs from the foramen magnum at the base of the skull all the way to the first or second lumbar vertebrae in the lower back.
Function:
The spinal cord plays a critical role in transmitting signals from the brain to the body and vice versa. It serves as the main pathway for sensory information, such as pain, temperature, touch, and pressure, to travel from the body to the brain. It also carries motor signals from the brain to initiate voluntary movements, control muscle coordination, and regulate reflexes.
Protection:
The spinal cord is safeguarded by several layers of protective tissues. The vertebrae, along with intervertebral discs, provide a bony enclosure around the spinal cord. Meninges, a set of three protective membranes (dura mater, arachnoid mater, and pia mater) cover and cushion the spinal cord.
Injuries and Disorders:
Damage or disease affecting the spinal cord can lead to debilitating conditions. Spinal cord injuries may result in loss of sensory or motor function, paralysis, or even complete loss of bodily functions below the level of injury. Disorders like spinal stenosis, herniated discs, or tumors can compress the spinal cord and cause neurological symptoms.