Sometimes people joke about there being two brains: a female one inside the head and a male one inside the trousers. If you think that I’m going to talk about this supposed second brain, then you’re mistaken. What I’m going to talk about is another brain – the one inside our digestive system. It is not as glamorous and as interesting as our sex drive but can be just as wild and unpredictable – and we use it far more because our digestive brain goes into action several times every day.
It’s fair to say that the intestine, which is divided into the large intestine and small intestine, is not the part of our anatomy we are most passionate about, nor the one that increases our pulse rate. No famous poet has written an ode to it, and normally artists are not inspired by the ‘beauty’ of the digestive system. Quite the opposite, in fact. The most common view of the gut is that it is an ugly body part that looks a bit like a snake, smells bad, and sometimes makes socially unacceptable and embarrassing noises.
However, I promise you that we have a true second brain in our insides and its neuronal function is very similar to the brain in our heads. Inside our bellies there is an extensive network of neurons located between the two muscular layers of the walls of the digestive system. Moreover, the structure of these digestive neurons is identical to that of neurons in the brain: both produce similar chemical molecules – neuro-transmitters and hormones that are mostly necessary for our intercellular communications and the correct functioning of the body.
The enteric nervous system
Let me introduce you to the enteric nervous system (ENS), our ‘second brain.’ This is not a metaphor; it is the official name accepted by medical professionals. The importance of the ENS was only demonstrated relatively recently with the publication of the work of Professor Michael Gershon, chairman of the Department of Anatomy and cell Biology at Columbia University, New York, and the forerunner of the new science of neurogastroenterology. This new area of speciality studies the symptoms of psychosomatic upsets that have a gastrointestinal expression and relates them to the central nervous system (CNS). Dr. Gershon has spent 30 years of his scientific career on an in-depth study of the attitude and behaviour of the human gut, and he has confirmed that our nervous digestion system has its own cerebral activity and intelligence.
According to new data, the total number of neurons found in the small intestine is around a hundred million. This figure represents a considerably higher number of neurons than in the spinal cord, for example. The brain in our gut is the main production line responsible for producing and storing the chemical substances called neuro-transmitters, most of which are identical to those found in the central nervous system (CNS), such as acetylcholine, dopamine and serotonin. These substances regulate our moods and our emotional and psychological well-being. They form a group of essential substances ensuring correct communication between the neurons and the body’s warning system. They represent the ‘words’ in the neuronal language. The presence of such a wide variety of neuro-transmitters in our intestines is a clear indication of the complexity of the rich digestive language and its ability to carry out neuronal functions and express its own emotions.
I can assure you that the relationship between the two brains, which involves hormonal, metabolic, and emotional levels, is very complex – we could even call it ‘intellectual’; it is also normally quite democratic and mutually respectful.
Evolution and the ancient brain
In the earliest developments of the cerebral cortex, the mental activity of our ancestors was more basic than ours today; it was guided more by instinct and intuition. Our distant relatives listened to their guts and acted on the signals their intestinal brains sent them. We ‘higher beings’, in contrast, have suppressed the intuitive capacity in favour of the all-powerful guiding voice of our mind and conscience.
Nevertheless, each of us from time to time has a ‘gut feeling,’ a warning that comes from deep inside and appears in intense or extreme emotional situations. It presents itself as a whole range of sensations, from a pleasurable thrill to a nervous knot, a hollow feeling, or a pain. This is our intestinal brain talking to us. Poor brain. To attract our attention and goad us into action, it has to shout loudly using its own ‘language’: bouts of diarrhea, spasms, or nausea.
The intestinal brain has developed alongside its higher twin, growing in size, and increasing the diversity and quantity of neurochemical substances produced. It has perfected its control of the vital functions and adapted to the new demands and needs of the human body. This evolution continues today.
After prolonged development, the enteric nervous system has been transformed into something much more important than a mere relic of our ancestors: it is now a modern system that performs highly complex vital functions without us having to make any mental effort or control its work.
The enormous hidden potential of your gut
We have the internal mechanisms we need for recovery and cure. Our body talks to us and warns us. If we could just decode its signals and take notice of them, we would be much stronger and healthier. Our two brains are both masters. They engage, talk, sabotage, or reinforce each other. It depends on the day and the emotional and digestive situation.
It has been shown that the digestive system has tremendous neurological and hormonal potential. This is why scientists and the pharmaceutical industry are currently devoting so much of their research and testing to neurogastroenterology. The question is, therefore: How can we take advantage of this valuable resource and make the best use of it for mental and digestive health?
From Digestive Intelligence, © 2014 by Irina Matveikova, published by Findhorn Press.