Motor nerve

A motor nerve is a nerve located in the central nervous system (CNS), typically within the spinal cord, that sends motor signals from the CNS to the muscles of the body. This is different from sensory nerves that send signals from the body to the CNS.

Structure

Motor nerves originate in the motor cortex of the brain. The cell bodies of motor neurons are located in the spinal cord, but their axons can extend to muscles throughout the body.

Motor nerves are composed of motor neurons, which are a type of nerve cell. There are two types of motor neurons: upper motor neurons and lower motor neurons.

Function

The primary function of motor nerves is to stimulate muscle contraction. They do this by transmitting signals from the brain and spinal cord to the muscles. This allows for voluntary movement of the muscles as well as the maintenance of muscle tone and posture.

Clinical significance

Damage to motor nerves can result in motor nerve diseases such as Amyotrophic lateral sclerosis (ALS), Spinal muscular atrophy (SMA), and Guillain-Barré syndrome (GBS). Symptoms of motor nerve damage can include muscle weakness, muscle atrophy, and twitching.

See also

• Nervous system
• Neuron
• Motor neuron disease
• Peripheral neuropathy

References

• A single isolated motor nerve cell of an ox spinal cord
  A single isolated motor nerve cell of an ox spinal cord
• Hand-book of physiology (1892)
  Hand-book of physiology (1892)
• 
  Forest of memory