The retrosplenial cortex is essential for forming the basis for contextual memories, which helps you recall events. Perhaps you remember exactly where you were when you learned of the events of September 11, 2001. Can you describe the room you were in? That’s your retrosplenial cortex hard at work, providing the context.
Your brain automatically maps whatever space you enter, but if nothing significant happens there, it doesn’t store the information very long. So, if you can’t describe the place you grabbed a run-of-the-mill lunch last week, maybe that turkey sandwich didn’t make a big impact on you.
The researchers say this work could help understand contextual memory disorders, such as Alzheimer’s disease.