Difference Between Central and Peripheral Nervous System

The key difference between central and peripheral nervous system is that the central nervous system includes the brain and the spinal cord while the peripheral nervous system includes all of the nerves that branch out from the brain and spinal cord and extend to other parts of the body including muscles and organs.

The nervous system is a vital organ system of our body that comprises a set of organs and a network of neurons. Furthermore, it comprises several other components such as other specialized cells, supportive cells, tissues, and biochemicals, etc., which help in the proper functioning of the nervous system. The major functions of the nervous system are acquisition, processing, comprehension, storing and transmission of information throughout the body. For this purpose, there are multiple organs, and sensory organs arranged all over the body, that have varied and very discrete functions.

Thus, depending on the distribution of these organs, we can divide the nervous system into two major components. Namely, they are the central nervous system and the peripheral nervous system. Here, the central nervous system acts as the main processing unit of the information while the peripheral nervous system connects the central nervous system to every other part of the body.

CONTENTS

1. Overview and Key Difference
2. What is Central Nervous System
3. What is Peripheral Nervous System
4. Similarities Between Central and Peripheral Nervous System
5. Side by Side Comparison – Central vs Peripheral Nervous System in Tabular Form
6. Summary

What is Central Nervous System?

Central nervous system is one of the two major components of the vertebrate nervous system. It consists of two main organs; the brain and the spinal cord. Hence, they are vital organs that should be protected from damage. Structurally, these two have very specific bony protective coverings supplemented by the other soft tissues.  They are the skull and the vertebral column. Our skull protects the brain while our vertebral column protects the spinal cord.

When considering the brain structure, there are three major parts in it such as forebrain, midbrain and hindbrain. The discrete regions of the forebrain mediate most of the functional mapping for the muscular movements, the sensory perceptions, and the executive functions. On the other hand, the midbrain is vital in keeping the person alive by coordinating the functions such as defensive physiological reflexes, respiration, and cardiac pacemaker control, etc. Structurally, midbrain constitutes a part of the brainstem as well. Finally, the hindbrain involves the formation of the cerebellum, which is essential in maintaining the balance of our body.

Figure 01: Central Nervous System

Spinal cord is the second major part of the central nervous system. It is a long, thin tubular structure composed of nervous tissue that runs from the brain stem to the lumbar region of the vertebral column. Also, three protective membranes surround the spinal cord. Spinal cord has distinguishable areas that function as the control hub for information from the brain to the peripheral nerves.  Furthermore, it coordinates reflex functions of the peripheral organs as well.

What is Peripheral Nervous System?

Peripheral nervous system is the second component of the vertebrate nervous system. It works as the connective line between the central nervous system and the body parts. Hence, it contains all the nerves and the ganglia for the nerves outside the central nervous system. Also, there are two major divisions of the peripheral nervous system that mediate voluntary and involuntary movements. They are the somatic nervous system and autonomic nervous system. All the involuntary actions such as blood flow, heartbeat, digestion, and breathing, etc., are linked with the autonomic nervous system. In contrast, somatic nervous system coordinates all the voluntary motor activities through cranial nerves and spinal nerves.

Figure 02: Peripheral Nervous System

Here, the involuntary ones are mostly for visceral organs. Thus, they are within the scope of the autonomic nervous system. The autonomic nerves that have distributions to cranial nerves, as well as forming spinal nerve plexi on occasion, are of two types. Namely, they are sympathetic and parasympathetic. The sympathetic nervous system is responsible for flight-fight responses and prepares our body for incoming threats. On the other hand, the parasympathetic nervous system is responsible for the rest and digest response and conserving the energy of the body.

What are the Similarities Between Central and Peripheral Nervous System?

  • Central and peripheral nervous system are the major parts of the nervous system.
  • Both are vital systems in processing and coordinating information within the body.
  • Also, both transmit nerve impulses.
  • And, both contain nerves or neurons.

What is the Difference Between Central and Peripheral Nervous System?

Central and peripheral nervous system are two major parts of the vertebrate nervous system. The difference between central and peripheral nervous system is that the central nervous system includes the brain and the spinal cord while the peripheral nervous system includes all the nerves that lie outside the central nervous system. Another difference between central and peripheral nervous system is the main function they perform. Central nervous system acts as the central processing unit of the information while peripheral nervous system transmits the created information of the central nervous system to every part of the body. Despite these differences, both nervous systems are managed by same cells called neurons. Furthermore, they have equal physiology, same mode of conducting information and similar support structures.

The below infographic shows the difference between central and peripheral nervous system as a side by side comparison.

Summary – Central vs Peripheral Nervous System

Nervous system has two major systems namely central nervous system and peripheral nervous system. Central nervous system is the main hub of processing information. Peripheral nervous system carries information from the central nervous system to every part of the body. This is the key difference between central and peripheral nervous system. Apart from that, central nervous system has two main organs; brain and spinal cord while peripheral nervous system has two systems; somatic nervous system and autonomic nervous system. Peripheral nervous system consists only of nerve cells and ganglia, unlike the central nervous system. This is also another difference between central and peripheral nervous system.

Reference:

1.Lewis, Tanya. “Human Brain: Facts, Functions & Anatomy.” LiveScience, Purch, 28 Sept. 2018. Available here
2.Anatomy of the Spinal Cord (Section 2, Chapter 3) Neuroscience Online: An Electronic Textbook for the Neurosciences | Department of Neurobiology and Anatomy – The University of Texas Medical School at Houston. Available here

Image Courtesy:

1.”13578831923″ by Siyavula Education (CC BY 2.0) via Flickr
2.”1201 Overview of Nervous System” By OpenStax,   (CC BY 4.0) via Commons Wikimedia