The Power of Habit: Why We Do What We Do and How to Change

by Charles Duhigg

Why had this gratitude habit proved so powerful? The researchers began examining the letters and discovered they tended to “use a greater proportion of ‘we’ words and positive emotion words, and a lower percentage of negative emotion words,” when compared to the writings of the introspective group. What’s more, when the researchers looked at the neurological activity of the grateful letter writers, they found “greater neural sensitivity in the medial prefrontal cortex, a brain area associated with learning and decision making.” In other words, developing a habit of writing grateful notes had put the letter writers into positive mindsets, had reminded them of how many friends and supporters surrounded them, had activated those parts of their brains that made it easier to make decisions and act. The letter writing habit had generated other mental habits that had made it easier to do things like put the dishes in the dishwasher, or forgive an incompetent barista.