The brain not only reacts to changes in the environment, but organizes our experiences into chapters based on what is important to us at each moment, so expectations and priorities influence how we remember the day’s events.
What determines how the brain divides the day into individual events that we can understand and remember separately? It seems that in addition to the environment that surrounds us, our mentality and expectations also influence the way our brain organizes the “index” of the day’s events, according to a new study published in the journal Current Biology that sought to answer this question. ask.
A clear example of this occurs when a person goes outside and enters a restaurant: at that moment, the brain begins a new “chapter” of the day, which causes a significant change in brain activity. These changes happen throughout the day as we face new environments, such as going to lunch, attending our child’s soccer game, or settling in to watch television at night.
The research team made interesting findings. Researchers wanted to better understand what drives the brain to delineate the events we experience, recording them as a new “chapter” of the day. One possibility is that these episodes are caused solely by large changes in the environment, such as moving from the street to a restaurant.
However, it is also possible that these chapters are dictated by internal scripts that our brain writes based on previous experiences, and that even large environmental changes can go unnoticed if they are not related to our priorities and goals at that moment.
How priorities and expectations influence the ‘script’ of the day
To test this hypothesis, the researchers created 16 audio narratives, each lasting three to four minutes. Each narrative occurred in one of four locations (a restaurant, an airport, a grocery store, and a conference room) and was about one of four social situations (a breakup, a marriage proposal, a business agreement, and a chance encounter). ).
The results showed that the way the brain breaks down an experience into individual events depends on what the person considers important at that moment. For example, when listening to a story about a marriage proposal at a restaurant, participants’ brains tended to organize the story around the events surrounding the proposal, until reaching (hopefully) the final “yes.”
However, the researchers were able to change the way the brain organized the story by asking participants to focus on the details of the couple’s dinner order. In these cases, moments such as choosing the dishes became new key chapters.
“Our research found that the brain is actively organizing our life experiences into fragments that make sense to us”
“We wanted to challenge the idea that changes in brain activity as we begin a new chapter of the day are just passive responses to changes in the environment,” said Christopher Baldassano, an associate professor of psychology at Columbia University who led the team with Alexandra De Soares, then a member of his laboratory. “Our research found that the brain is actively organizing our life experiences into fragments that make sense to us,” he added.
The researchers measured where the brain created new chapters both by watching MRI scans to identify new brain activity, and by asking another group of participants to press a button when they thought a new part of the story had begun.
They discovered that the brain divided stories into separate chapters depending on the perspective they were focused on. Not just in the restaurant proposal story: in a story about an airport breakup, a participant who paid attention to airport details could identify new chapters as they passed through security or arrived at the gate. Likewise, in a story about a business agreement in a store, the chapters could focus on both the steps of the agreement and the phases of the purchases, depending on the attention given.
In the future, the researchers plan to explore the impact of expectations on long-term memory. As part of the study, they also asked participants to remember as much as they could about each story. They are analyzing data to understand how the perspective adopted while listening influences the way events are remembered. This study is part of a broader effort to build a comprehensive theory about how real-life experiences are broken down into event memories. The results suggest that prior knowledge and expectations play a key role in this cognitive process.
Baldassano described the work as an exciting project: “Tracking activity patterns in the brain over time is a huge challenge that requires complex analysis tools,” he said. “Using meaningful stories and mathematical models to discover something new about cognition is just the kind of unconventional research in my lab that makes me most proud and excited,” he concludes.
