I’ve touched on this for Sapien Medciine’s Superhuman Genius v2.0
It appears people who have such vivid memories have very large amygdalas with superior connections to their hippocampus. Episodic memory is the name of the game, although having there are those like kim peek who have both sides of the coin with declarative (facts/semantics) and episodic (emotional/events), but Kim would have lack a corpus callosum and fault temporal lobe so is a hobbledehoy in any other playing field of cognitive function
Both brain areas appear to be superior vs the average person. eximiously the hippocampus -
Neuro4Kids | Superior Autobiographical Memory: The Hippocampus Hard-drive | by Rohan Poosala | Medium
[Neuro4Kids | Superior Autobiographical Memory: The Hippocampus Hard-drive | by Rohan Poosala | Medium]
(Neuro4Kids | Superior Autobiographical Memory: The Hippocampus Hard-drive | by Rohan Poosala | Medium)
And the things is a fallacy/loblogic ipsedixitist dogmatic doctrinarian anoia/idiocy. EVERYONE has a photographic/eidetic memory, but imperfect recall.
There is a new study on DAMB receptors where they studied flies that have these receptors and how the receptors played a role in forgetting/lethean. They could remember everything because they could not forget!
So i would approach this with the inverse thinking mental model of reverse engineering what makes such abilities possible.
Control what you forget, and you never haver to worry about what to remember.