Translate this website into the following languages:

Close Tab
UC San Diego Health
menu iconMenu
search iconSearch
US News and World Report Badge for Neurosurgery 

About Peripheral Nerves

The Peripheral Nervous System (PNS)

Peripheral nerves are an integral part of the human nervous system. The nervous system consists of:

  1. Central nervous system (brain and spinal cord)
  2. Peripheral nervous system

Peripheral nerves reside outside your brain and spinal cord. They relay information between your brain and the rest of your body.

The peripheral nervous system is divided into two main parts:

  1. Autonomic nervous system (ANS): Controls involuntary bodily functions and regulates glands.
  2. Somatic nervous system (SNS): Controls muscle movement and relays information from ears, eyes and skin to the central nervous system.

Nerves In the Peripheral Nervous System

  • Brachial plexus (radial nerve, median nerve, ulnar nerves)
  • Peroneal nerve (foot drop)
  • Femoral nerve
  • Lateral femoral cutaneous nerve
  • Sciatic nerve
  • Spinal accessory nerve
  • Tibial nerve

Within the two main areas of the peripheral nervous system are three types of peripheral nerves:

  1. Sensory: Connects the brain and spinal cord to your skin and allow you to feel pain and other sensations.
  2. Autonomic: Controls involuntary function (e.g., blood pressure, digestion, heart rate).
  3. Motor: Connects the brain and spinal cord to muscles to stimulate movement.

When we move, the brain sends a message to the spinal cord. From there, the nerves carry the message to the necessary muscles to make them contract and produce movement. Similarly when we touch an object, sensory information is carried through the nerves to the spinal cord and then to the brain so that we can make sense of that information.

Symptoms of Peripheral Nerve Disorders

Peripheral Nerve

Peripheral nerve disorders distort or interrupt messages sent between the brain and the rest of the body. This can result in:

  • Painful cramps
  • Numbness
  • Muscle weakness (most common symptom)
  • Tingling or burning

Unlike the brain and spinal cord, peripheral nerves can regrow after an injury. However, surgery is often required to reconnect the peripheral nerves so that movement and sensation can be restored.

Make An Appointment

Call 858-657-5085

Meet Our Specialists

Related Links

Our bimonthly newsletter delivers healthy lifestyle tips, patient stories and research discovery news. Subscribe: