Yale scientists discover how stress changes the brain to make memories stronger
Yale scientists have uncovered how the stress hormone cortisol helps the brain turn emotional experiences into stronger, longer-lasting memories. The discovery reveals that stress can reshape communication between brain networks involved in emotion and memory, potentially explaining why certain moments are so difficult to forget.
Key points
- Yale researchers found cortisol strengthens emotional memories by changing brain networks for emotion and memory.
- The study used hydrocortisone pills and fMRI scans to separate emotional intensity from memory formation.
- Cortisol made emotion networks more consistent and memory networks more specialized for emotional information.
Yale University scientists have discovered how stress changes the brain to make emotional memories stronger. The study, published in Science Advances, shows that cortisol alters how brain networks involved in emotion and memory function and communicate.
The research helps explain why intense or meaningful experiences are remembered better, while other experiences fade.
How the study was done
Participants took a pill containing hydrocortisone, a form of cortisol, or a placebo. They viewed pictures while undergoing functional MRI scans and reported their emotional reactions. The next day, researchers tested their memory of the pictures.
Each person completed the experiment twice, once with hydrocortisone and once with placebo, in a double blind design. The team analyzed functional connectivity during brief five-second trials to predict emotional intensity and later memory.
Stress responses are fundamentally adaptive and can help you form strong memories -- but this is specific to experiences that you find to be emotionally intense or meaningful.
— Elizabeth Goldfarb
What the findings show
Cortisol improved memory for emotionally significant experiences. It also strengthened emotional memory through distinct changes in brain networks for processing emotion and forming memories.
In emotion networks, cortisol produced more consistent activity and increased engagement. In memory networks, it made activity patterns more specialized for emotional information. The hormone also increased coordination between the two networks.
Corresponding author Elizabeth Goldfarb said, "Stress responses are fundamentally adaptive and can help you form strong memories -- but this is specific to experiences that you find to be emotionally intense or meaningful."
