Why are flashbulb memories so long-lasting?

Flashbulb memories are a type of long-term memory that normally involves an extremely emotional event. One theory proposes that flashbulb memories last so long because of the physiology of the brain.

The amygdala is responsible for emotion. The hippocampus is involved in long-term memories. It just so happens that these regions are very close in proximity with each other. Memories with strong emotions tie these two regions together, thus resulting in a longer-lasting memory.