Scientists have long wondered how the brain updates itself with new information and memories. Some ideas revolve around chemical changes in specific neurons, while others focus on structural shifts among brain cells.
Dr. Tomás Ryan from Trinity College Dublin is among the neuroscientists who have explored these questions by tracking cells involved in learning.
New findings suggest memory formation hinges on connections between groups of engram cells, which are neurons thought to capture and store distinct experiences.
How memories become linked
Researchers believe each experience leaves a pattern of brain cell activation that can be switched on later. To see this process in action, neuroscientists tracked two sets of engram cells, each tied to a different memory.
They discovered that when one set of cells was reactivated, the other set sometimes lit up too, as if the memories had become linked.
This idea runs counter to the old notion that an individual neuron stores an entire memory. Instead, the memory might be in the connections these cells build and reshape over time.
Such structural rearrangements help us handle new information without losing old experiences.
