Brain Gut Connection

Brain-Gut-Chess-2Unfortunately, it is not uncommon to hear people say that functional bowel problems are all in your mind.
And yes, there probably are people out there that may think you are exaggerating or trying to get attention. If you have IBS or another functional gut disorder, you are far from ‘faking’ or imagining it.
This association most likely comes from comes the link between stress and IBS.
It is important to know that stress is not the cause of IBS. Stress however can make the symptoms worse…but how? To answer this question we need to know more about the brain and gut and how they function in relation to each other.


Brain-Gut Axis

It begins with the gut and brain originating from the same clump of tissue in the embryo. As the embryo evolves and grows, the the brain to one end and the gut slides down the opposite end. That does not mean they are not still connected. In fact,the brain and gut are still connected via the Vagus nerve or visceral/peripheral nervous system.

There are strong connections in the nervous system between brain and the gastrointestinal system. These are in the form of neurotransmitters that relay information to and from the gut to the brain. Therefore, the brain signals to the gut system via nerves that carry messages and control the pattern of activity in the gut.

In fact the gut contains as many neurons(nerve cells) as the spinal cord. This neural network in the gut is called the Enteric Nervous System ( ENS), also known as the second brain or mini brain (because of its ability to work with and independent of the brain (Central Nervous system).An example would be to look at the ENS as a library of programs for different gut behaviours.

Chemicals are released by the CNS (acetylcholine and adrenalin) that tells the stomach when to produce acid in the stomach, when the churn the food and when to rest. Movements through the intestines is also helped by similar signals. The digestive system responds by sending electrical messages to the brain, creating such sensations as hunger, fullness, nausea pain, discomfort, and possibly sadness and joy. (Woolston, 2002)

Another important neurotransmitter for digestive functioning is serotonin(5-HT). It is not common knowledge that 95% of the serotonin in the human body is found in the digestive tract. It is a vital vital part of the communication system between the brain and the gut. It also seems to play a part in motility, sensitivity, and secretion of fluids. It is also the ‘feel good’ hormone which helps to explain the correlation between anxiety/mood and functional gut problems. (Mulak & Bruno 2004)

(Woolston C, 2002; Surprising Link Between Mood and Digestion. Gut Feelings: CONSUMER HEALTH INTERACTIVE
Mulak A & Bonaz B: Irritable Bowel Syndrome: A model of the brain gut connection. Medical Science Monitoring, 2004; 10(4)RA55-62.