It's interesting that you posted this-- DD was recently chatting with me and a friend (also HG+ college student) about children's museums and the like-- and she recalled details of a children's museum visit that were a little fuzzy around the edges, but sufficiently detailed that I was astonished-- she was reminding ME of an outing which had occurred when she was 13months old. She had thought that she was "less than four" but she definitely wasn't confabulating/conflating different events into a single narrative, which was what I'd expected. In fact, I initially dismissed the narrative as not being an accurate recounting of a trip to a different location which had taken place when she was nearly FOUR-- because her details didn't match that trip. Then she started telling me other details, and I finally remembered, because she mentioned something really architecturally distinctive. It was definitely a day that I hadn't though much about in about 13 years.
There were some details, in fact, which were contrary to a photo taken that morning-- for example, in the photo she is holding a pair of shoes (which she loved-- and she reported that when I produced the photo later after hunting through a box of early photos), but it was not the pair that she wore that day. She had also remembered what she was wearing-- and what's more, she remembers things that I don't-- such as which car we took, and what I was wearing.
She remembered the layout of part of the children's museum in Minneapolis, circa 1999-2000. We moved when she was 18months, and went just once when she was 13months old, during a one-week period between getting her first medic-alert bracelet and having it resized for her tiny wrist. I know that because she was wearing it on her ankle instead, that day. I remember that because it dictated what kind of shoes she could wear (not her favorite ones in the photo), and it drew attention from another adult.
I have to think that memory is entirely authentic-- I remember the day fairly well, but it wasn't a "special" day which becomes the stuff of family lore or anything. The detail is stuff that I remember only because of my heightened anxiety about her-- it was really our first outing after her diagnosis, and it was stressful-- something that she also recalls. She recalled that we didn't permit her to venture where we couldn't be within arm's reach and maintain a line of sight to her, and that this was annoying. She also recalls wanting to play with the older of a pair of children, there with an older adult (grandparent?)-- the girl was about 7, and the boy was about 4 (I recall that family).
Many of her very early memories are like that, with sensory detail, and memories of people (but not necessarily their faces or identities, just what they were like and the social interactions/dynamics with others). She remembers colors and spatial details relatively well, too.
I also remember snippets of my very early childhood-- before age 3-- but DH categorically does not.
Sadly, DD had much better recall of some of that stuff (from before age 10) that she'd invested so much time into (she went through a Yad Vashem phase at about age 8, for example) a couple of years ago. I think that her PTSD and trauma has wiped places in her memory-- or at least impaired her retrieval so that it amounts to the same thing.
It was interesting to me that this astonishingly detailed and intact memory had surfaced so casually. I don't think she's ever reinforced it, so it has always just been there in her brain, I guess.
Anyway-- that's my anecdote about early memories.
I know that rehearsal is apparently hypothesized to be how memory is consolidated and how retrieval pathways are thought to work.
I'm not sure that rehearsal plays that large a role in consolidation/retrieval, at least for DD. I'm not sure that it does for me, either-- I recall things that have sensory detail associated with them, mostly-- auditory and tactile, for me personally. And they aren't things that I necessarily have thought about much during my lifetime. I can recall my great grandmother singing to herself (and not in English)-- she died when I was five, and I last saw her when I was three, so that memory is earlier than that. I picked something that I haven't considered in years for that example, btw-- that is, I went through my mental roladex of family members who died when I was a young child, and saw seldom beforehand, just to see if I had clear memories of it, and if so, what the nature of them might be.
I kind of wonder if the type of memory you're referencing isn't a different sort of encoding mechanism, though, Bluemagic. That is, purely informational material seems to be much more volatile long-term in kids. Is that it?
Because yes, I'd say that stuff seems to be much more use-it-or-lose-it. I knew (apparently) a TON about archaeology as a child of 4-6yo, but I recall very little about that now, and didn't even in my teens. It no longer mattered so much to me, I guess.
