New research has uncovered how the brain organises daily experiences into meaningful segments, much like scenes in a film. While we perceive life as a continuous flow, our brains automatically break memories into distinct moments. Scientists have long debated whether these boundaries are set by environmental changes or if they are determined by personal interpretation. Now, a study led by Christopher Baldassano, associate professor of psychology at Columbia University, suggests that the brain actively chooses these transitions based on our goals and experiences, offering new insights into memory formation. How does the brain decide where one memory ends and another begins? To explore this, Baldassano and his team conducted a brain-scan experiment using functional magnetic resonance imaging (fMRI). Volunteers listened to narratives involving various scenarios, such as a business deal, a proposal, and a breakup, while their brain activity was recorded. The research focused on changes in the medial prefrontal cortex (mPFC), a brain region involved in processing ongoing events. The results showed that when key social events in the narratives occurred, such as the …