The first word that came to me was aftermath. But it doesn't quite do it. Because aftermath refers to the "lingering" effects and what I'm looking for is the memory, the shadow.
Is there a word/phrase for that?
If the memory is upsetting:
- Agonizing physical or mental pain; torment.
Flashback can be used in that sense - with appropriate context. It is often used to describe vivid, traumatic memories - like those of a soldier, for instance.