I believe now that we're constantly in nondecisionmaking mode. We're constantly running patterns or taking actions without conscious command or choice, similar to blood running from a cut.

This is one of the main theses of The Power of Habit.

When a rat first navigates a foreign environment, such as a maze, its brain is full of activity as it works to process the new environment and to learn all the environmental cues. As the environment becomes more familiar, the rat's brain becomes less and less active, until even brain structures related to memory quiet down a week later. Navigating the maze no longer requires higher processing: it has become an automatic habit.

The process of converting a complicated sequence of actions into an automatic routine is known as "chunking", and human brains carry out a similar process. They vary in complexity, from putting toothpaste on your toothbrush before putting it in your mouth, to getting dressed or preparing breakfast, to very complicated processes such as backing one's car out of the driveway. All of these actions initially required considerable effort to learn, but eventually they became so automatic as to be carried out without conscious attention. As soon as we identify the right cue, such as pulling out the car keys, our brain activates the stored habit and lets our conscious minds focus on something else. In order to conserve effort, the brain will attempt to turn almost any routine into a habit.