Thinking Beyond Science

There is a buzz of constant activity beneath our skin. We are perpetually flowing, pumping, sucking, squeezing, bursting, repairing, and rebuilding. A whole crew of ingenious organs works so perfectly and efficiently together that, in an adult human being, they require as much energy as a 100-watt light bulb.

Our lungs are so cleverly designed that we use energy only when we breathe in. Breathing out happens without any expenditure of energy at all. If we were transparent, we would be able to see the beauty of this mechanism: like a wind-up toy car, only bigger, softer and more lung-y. While some of us might be sitting around thinking Nobody cares about me!, our heart is currently working its seventeen thousandth 24-hour shift – and would have every right to feel a little forgotten when its owner thinks such thoughts.

We develop, roughly speaking, from three tubes. The first tube runs right the way through us, with a knot in the middle. This is our cardiovascular system, and the central knot is what develops into our heart. The second tube develops more or less parallel to the first along our back, then forms a bubble that migrates to the top end of our body, where it stays put. This tube is our nervous system, with the spinal cord including the brain at the top, and myriad nerves branching out into every part of our body. The third tube runs through us from end to end. This is our intestinal tube – the gut.

Each of the two sphincters looks after the interests of a different nervous system. The outer muscle is a faithful servant of our consciousness. When our brain deems it an unsuitable time to go to the toilet, the external sphincter obeys and stays closed with all its might. The internal sphincter represents our unconscious inner world.

The main thing for the internal sphincter is to keep everything comfortable and in its place. These two sphincter muscles have to work as a team. When what’s left of our food reaches the internal sphincter, that muscles reflex response is to open. But it does not just open the floodgates and let everything out, leaving the outer sphincter to deal with the onrush. First, it allows a small ‘taster’ through. The space between the internal and external sphincter muscles is home to a large number of sensor cells. They analyze the product delivered to them, test it to find out whether it is solid or gaseous, and send the resulting information up to the brain. This is the moment when the brain realizes: it’s time to go to the toilet! … or maybe it’s just a bit of wind? It then does what it is so good at, with its conscious awareness: it adapts to the environment we find ourselves in. It compares the information it receives from our eyes and ears to the data in its memory bank of past experiences. In this way, the brain takes just a matter of seconds to make an initial assessment of the situation and send a message back to the sphincter: ‘I’ve had a look, and we’re at Great Aunt Berthas, in the living-room We might get away with breaking a little wind, if we can squeeze it out silently. Anything more solid might not be such a good idea’

The external sphincter gets the message, and dutifully squeezes itself closed even more tightly than before. The internal sphincter receives this signal from its more outgoing partner and respects the decision for now. The two muscles work together and maneuver the taster back into the holding pattern. Of course, it will have to come out sooner or later, just not here and not now.

If we suppress our need to go the loo too often or for too long, our internal sphincter begins to feel browbeaten. In fact, we are able to re-educate it completely. That means the sphincter and the surrounding muscles have been disciplined so often by the external sphincter that they become cowed. If communication between the two sphincters breaks down completely, constipation can result.

Source – Gut: The Inside Story of Our Body’s Most Underrated Organ by Giulia Enders, Jill Enders (Illustrator)

Goodreads – https://www.goodreads.com/book/show/23013953-gut