“All our life, so far as it has definite form, is but a mass of habits,” William James wrote in 1892.
One paper published by a Duke University researcher in 2006 found that more than 40 percent of the actions people performed each day weren’t actual decisions, but habits.
While each animal wandered through the maze, its brain—and in particular, its basal ganglia—worked furiously. Each time a rat sniffed the air or scratched a wall, its brain exploded with activity, as if analyzing each new scent, sight, and sound. The rat was processing information the entire time it meandered.
And within their brains, something unexpected occurred: As each rat learned how to navigate the maze, its mental activity decreased. As the route became more and more automatic, each rat started thinking less and less.