Study reveals how the brain divides days into 'movie scenes'

New brain scans may help unravel a fundamental mystery about how our memory works on a day-to-day basis.

Similar to how a movie is divided into scenes, our brains organize our memories of each day into segments — separating when we went out to lunch from when we came home from work, for instance. But in movies, directors and editors decide when one scene ends and a new one begins. So how does the brain choose?

In theory, shifts in our environment may dictate when we've "entered a new scene," or instead, the brain may somehow determine the boundary between scenes.

Now, in a paper published Oct. 3 in the journal Current Biology, researchers found that the latter theory is likely correct — and that we may have more control over how we interpret the day's events than scientists previously thought.

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Senior study author Christopher Baldassano, an associate professor of psychology at Columbia University, and his team wanted to understand what leads the brain to form boundaries around daily events, essentially changing from one "scene" to another. The leading theory has been that these boundaries are raised by a major change in the environment, such as when you walk into a movie theater or enter a grocery store, going from outside to inside.

However, another hypothesis suggests that these boundaries are created by our own past experiences and feelings about certain events or environments. So, while a change in environment can affect the segmentation of someone's day, it's possible that this influence can be overridden by our own priorities and goals.