Here is link to an article in Psychology Today about a Yale University brain study. This new study looked at the effects of mindfulness meditation practice on the brain state called the ‘default-mode network’ or DMN. The DMN has been shown to be important in self-referencing (helping us shape our view of ‘who we are’) and in mind-wandering. While mind-wandering may be helpful sometimes (it is linked to creativity when you are aware that you are mind-wandering) most of us mind-wander up to 50% of the time, and without any awareness that we are doing so. This in effect means we are not present with what we are doing for half our lives, instead, our minds are wandering to other sorts of thoughts – worries, ruminations, thoughts of the past or future, etc.