The Brain's Default Mode and the Price of Separation

About 46.9 percent of our waking hours, our minds wander unintentionally. That statistic from a 2010 study by Killingsworth and Gilbert points to something deeper, according to neuropsychologist Dr. Aldrich Chan: the human brain is wired for separation from the immediate present. This capacity—which he calls the MOTS network (mental time travel, others, and the self)—allows us to simulate futures, recall pasts, and reflect on ourselves. But it also creates a chronic sense of disconnection from nature, from our bodies, and from each other.

The SAD Theory: Separation, Alienation, Discord

Chan has developed an original framework called the SAD theory to explain how human cognition creates suffering. The first phase, separation, describes how the brain's default mode network (DMN) and central executive network allow us to suspend the immediacy of space and time. The DMN enables mind-wandering, self-reflection, and social cognition. The central executive network handles goal-directed activity and analysis. Together, they gave humans symbolic thought—evident in cave paintings from 64,000 years ago—but also created the experience of being separate from nature.