Or in the case of memories that seem to alter this often I think Terry Pratchetts "inspiration particle" is more relevant than anything like science. How photons act in the real world, and how they act after forty odd years of a remembering are entirely different. Memories are often more like dreams, and the version we tell others to make the story interesting become what we though happened, regardless of pesky facts. We see it all the time, people who think certain foods tasted better before, who remembered TV shows having better effects (or in the case of Doctor Who people imagining the sets wobbled, despite a lack of wobbling on the screen), people who are sure something amazing happened on holiday as a kid, because their family would tell them, rather than because it happened.
When any useful data changes too much, you have to assume the memory is not a good basis for investigation as you no longer have a datum to measure others from.
This first page of this article on Cracked of all places highlights some of the perils of relying on memory, and just how easy it is to manipulate it:
5 Common Crime Fighting Tactics (Statistics Say Don't Work)