Gandalf the Grey or Gandalf the White? Well your brain is both
Your brain is often referred to as the 3 pounds of "grey matter" between your ears.
It's "grey matter" because it literally looks greyish in reality - the bulk of our brains are formed by neurons, which are greyish in colour.
But if you notice, in the image above, there is also "white matter".
What is this "White Matter"? (if your answer is bone.... please give yourself a punch).
This white matter is myelin.
||| Myelin is a key reason why what we think or do often becomes easier and more natural
First, don't be intimidated by the picture above. It's just how our neurons (our brain cells) look like.
On the left side of the picture, the "nerve cell", this is simply the body of the cell.
On the right side of the picture is the "the nerve cell fibre" - you can think of this as the "mouth" of the cell. After the cell body decides on something, it tries to tell other cells through its "mouth".
Myelin is a white (white matter, remember?) sheath of fat and protein that wraps around the connecting tube between the cell body and the cell's "mouth".
What causes this fatty sheath of myelin to develop?
Repetition. When we repeatedly think or do something, myelin starts to develop. And from the picture of the brain above, you can see that there is a fairly significant amount of myelin in our brains.
And so what does myelin do?
Myelin makes it faster and easier for the cell body to send messages to the mouth, and in turn to other cells. The speed and efficiency at which a message that passed out is important. Think about it like social media vs print media. When something happens, Twitter, Facebook, and Instagram will quickly buzz with activity and discussion. In contrast, newspapers only get printed the next day - by the time the newspapers are out, social media had already covered the news extensively.
Similarly, cells with myelin can quickly disseminate ideas or information to other neurons, which in turn causes them to start triggering their own messages and reactions.
The presence of myelin is the reason why, when we answer the same questions or perform the same actions, we can do so much quicker and seemingly more automatically. In turn, this makes it feel easier.
But it's also important to note that the development of myelin is values free. It doesn't judge whether the answer or action we consistently give is correct or not. This also explains why it is hard to change a particular way of thinking, or a say an incorrect action which you've become used to.