Narrator: This is Science Today. It's common knowledge that fear burns memories into the brain, but new research by the University of California, Berkeley now reveals how. Graduate student researcher Aaron Friedman explains that, during a fearful event, the brain's emotional center — called the amygdala — promotes the creation of new neurons in the hippocampus — a part of the brain where memories are formed.
Friedman: It's increasing the rate at which these new neurons are being made, making more neurons to respond to the amygdala, and starting to encode the emotional aspect of that memory.
Narrator: Friedman and his colleagues used a rat model to determine the amygdala's role in creating neurons. They suspect that these new neurons act as a blank slate for the memory and, later, help the brain to recall the emotional aspects associated with the initial experience.
Friedman: So not only is the amygdala helping to create this population of new neurons that might participate in memory, but then later in response to fear, it's activating those cells and, we think, helping them to become part of a network that's encoding the fear memory.
Narrator: For Science Today, I'm Larissa Branin.