This post is about taking a crap. As I was reading Gut - Inside Story of Our Body's Most Underrated Organ, I was impressed to find that this daily necessity of ours is actually more sophisticated than I thought.
Every time we go to the toilet, it's an effort by two nervous systems (The brain and the Gut) working tirelessly in tandem to dispose of our waste as hygienically as possible.
Within your ass hole (pardon my language), there are these muscles called the sphincters. And there are 2 of them, the internal sphincter and the external one.
You should be familiar with the external sphincter, it's the muscle you control whether to let the crap out.
It's the reason why you can hold going to the toilet until you reach home.
The internal sphincter works for the Gut, while the external sphincter works for your brain.
When what's left of our food reaches the internal sphincter, its reflex response is to open.
But it doesn't just open the floodgate and let everything out, instead it allows a small "taster" through.
This space between the internal and external sphincter muscles has a large number of sensor cells. They analyse the product delivered to them, test whether it's solid or gaseous, and send the result 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".
The brain will then send a message back to the sphincter: "I've had a look and we're now seated in our house's toilet, so open up!"