I suspect a slow decline affects some of us, just like the cognitive decline of senile dementia. I’ve just attended a thirty year Uni reunion and I had no trouble recognising just about everyone there (about one hundred and ten old classmates from a graduating class of around two hundred), whereas as hard as I try, I frequently have trouble recognising my kids’ teachers and their friends’ parents when they greet me in the shops & streets (out of context). They’ll look familiar, but I just can’t place them or remember their name. These are people I’ve only met in the last decade, so it appears I am not as good at imprinting memory as I once was, but retrieval of old memories seems to be working well, which fits with well known difference between old and new memories. Unfortunately, I’m easier to recognise and my kids are well known in the community, so I often feel terrible and try to make up for it by being very polite.