What is the Enteric Nervous System?

Most people believe that man has only one nervous system that is further divided into sub-systems. There is, however, a second nervous system in the body. It is called the enteric nervous system and it has grabbed the attention of medical researchers who suspect that it just might have the ability to operate as a second "brain." Where exactly is the enteric system?

The esophagus or food tube, stomach, small and large intestines are lined with sheaths of tissue containing neurons (nerve cells) that are "soaked" in the same neurotransmitters that exist in the brain and are influenced by them. Neurotransmitters are substances necessary for the transmission of messages throughout the nervous system. The enteric nervous system has been declared a distinct entity being a complete network of neurons neurotransmitters, and special proteins responsible for communications, "thinking," "remembering," and even "learning."

Is a "gut feeling" produced by a thinking enteric nervous system or are both nervous systems more closely intertwined than doctors think? This is very possible especially when considering embryonic development. A mass of tissue known as the neural crest forms during the development of a baby. Part of the neural crest becomes the central nervous system while the other part develops into the enteric nervous system. It is no wonder that the "central" brain can upset and throw off kilter the "brain" of the enteric nervous system and vice versa. This is why this system is often called the nervous system of the gut. However, it is more accurate to describe it as the nervous system of the gastrointestinal system since the esophagus is involved and the esophagus is not the gut.

Effect of the Central Nervous System on the Enteric Nervous System

It's interesting that prescription and over-the-counter medications as well as herbal remedies that affect the central nervous system also affect the enteric nervous system. For example, drugs to alleviate pain, such as morphine, always affect the gut. The side effects of prescription drugs and most over-the-counter medicines are almost always very harmful while those of herbal remedies might or might not be harmful. In fact, some of them are beneficial. It has also been discovered that the "brain" of the gut is intricately involved in gastrointestinal conditions such as colitis.

Further evidence of the effect of the enteric nervous system on the body and its insuperable relationship with the brain include observances when faced with sudden fear, embarrassment, anger, or sadness. "Butterflies" can form in the stomach when an individual becomes queazy or nervous. Constant worry is often the cause of the formation of stomach ulcers. There are also the times when someone can have a "lump" in the throat brought on by his or her mental state.

Source:

Dr. Rosalyn M. King, Professor
The Enteric Nervous System: The Brain in the Gut
King's Psychology Network