Act III of episode 585 of This American Life (a WBEZ radio show broadcast on NPR and distributed via podcast) discussed this phenomenon and spoke with a few individuals with HSAM:
https://www.thisamericanlife.org/585/in-defense-of-ignorance...
One of the individuals was a script supervisor in Hollywood responsible for ensuring continuity between scenes during filming. But it also ventures into powerful emotionally resonant territory, touching on the bittersweet implications of experiencing loss when memories never fade.