Bioshock (1) had some (alleged) memory hallucinations caused by the ADAM you had used - memories from the gentic codes from the Splicers the ADAM had been recycled from. It was used as an alternate presentation of plot events in telling various stories/events in previous inhabitants lives.
Ghosts in Rapture - a Better Explanation (since DNA/RNA cannot hold 'memories')
Sorry RNA/DNA containing memories is a 30 years gone Sci-Fi idea. There is no way to build brain patterns either electrical temporary or physical synaps links from a maybe long molecule that encodes about 20 million(DNA) ACTG combinations (or less for RNA or DNA 'patches') -- to make this Video-Recording-like 'ghost story' effect work.
Recycled ADAM might have breakdown contaminants which exacerbate brain behaviors leading to 'ghost' delusions.
Subliminal whisperings (someone hiding in the woodwork? PA systems, whatever, hidden wall scrawlings) ? Jack who is now a Splicer and potentially insane hears them accumulatively and subconsciously, sees in some places the setting/props/results of the events that allegedly unfolded and his brain fills in an apparition to his conscious mind. This 'brain filling in the details' is a well documented phenomenon.
Possibly the 'ghost' story he sees is not real (something different than what actually occured - if anything did) but again the result of ADAM's effects on his mind. We dont ever see the original events to compare. We do get to hear some events via Accu-Vox recordings which are detailed and played out/hinted at. Some happen to get heard after the ghost story apparition though, so its back to subliminals in the ambient location *OR* (heh) we hallucinate the played recording(think we hear it a certain way) to match the apparition we already 'saw' ??? Hows that for being Philip K Dick ??.
Also possible - Coincidence that Jack imagines pretty much the same 'story' as the tapes reflect (if they hadnt been heard yet ...) Note - awful lot of 'coincidence' contrived in these games so whats a little more matter ???
The problem is DNA doesnt encode that - its all environmentally (life experience) generated upon the basic 'blank' structure of your brain. The detail 'info'/'data doesnt go down to that fine a level (and with 20mil crude bits of data even if it did, it is not enough info for the literally billions/trillions of very specific synaps connections in your brain to holographically build up just one of these ghost stories).
As for the memories fed into the "First Utopian" -- remember THAT it is quite likely ( only ?) a delusion on Sofia Lamb's part. Apparently it never actually worked -- did it ? Gil Alexander was turned into a freakish monstrocity and he doesnt actually say that anything of the sort worked on him. Lamb was crazy as a loon thinking to eliminate human nature from humans (apart from doing THAT somehow being superior). SO she might believe in that 'memories' idea but it has no basis in reality beside some 'ghost story' effect some people think they saw, but she couldnt directly analyze herself as she wasnt a Splicer. Has Sofia really even seen any such result (and Eleanor as the 'second try' might be clever enough to play along and use it against Sofia) or had that part really even gotten started yet. (vagueness is largely what we get).
(BTW- since 'ghost stores' were explained to be missing BS2 because they became too muddled with too much recycling - passing through too many people - weirdness with the Big Sisters and such ...
What kind of 'memory' gibberish in the ADAM might be left to use any more (assuming that idea even worked) ???)
Little Sisters seem to see 'dreams' ? Well same effect as mentioned way above (they are as ADAM addled as any Splicer). Who knows what they have seen or heard from some combination of Splicer talk, their previous life, their conditioning, media they come upon, etc.... They already have that weird view we saw thru their eyes (however THAT was supposedly done - we took POSSESSION of a 7 year old child - and we saw not just through their eyes but through their conditioned filtering how they see things ... neat but who knows what weirdness Lamb and Alexander had done to them (new ones) - Since I rely on Psi effect stuff to try to turn the plasmids into sci-fi instead of fantasy -- i can allow some kind of guided mental projection potentially with lasting results.
Eleanor herself ... same thing. She might think she sees dreams from Little Sisters (who share her genetics... whatever that means) but she's been subjected to even more ADAM (first as a LS and later with whatever Sofia pumped into her and whatever else was done to her).
The memories Eleanor feeds into Delta ? Well his brain was reconstituted (or never became mulch and was intact enough still to revive) and who knows how selective SHE was to pre-pick 'conditioning'/imaging/memories to foster Delta coming to save her. Delta has a 2 way radio (and a TV transmitter that seems to be used to watch what he sees??? why not a image reciever of some kind too?), but what other brain injection mechanisms was used with BDs (or at least attempted with his experimental model) to issue them orders and such.
Funny is that the whole construct of 'Delta seeing Lamb order him to kill himself' could have been some recording and this daddy 'Delta' is just some (any) available Alpha body/brain which those memories were impressed upon by Eleanor's modified Vita Chamber.
The above brings up an interesting point in that Sofia Lamb's delusion required lots of Memory-rich ADAM to be 'extracted' to build her Franken-utopian. Did that mean that anyone who wasnt already a Splicer would be forced to become one (likely with nullified Tonic/Plasmidsthat would be useless/non-empowering to the 'future extractee'...). The addiction certainly would make them more susceptable to her coersion (if the thuggery wasnt being effective enough).
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A Strange Explanation for (some of) the Ghost Stories :
Since Genetic Memories are physically impossible (explained elsewhere), and this is 'Classic' Rapture ...
Ghost Stories (assisted a bit by ADAM hallucination/derangement) is actually done by crazy "Mime" Splicers covered in phoshorescent/Bioluminescent paints (BUT some talk ?? - I DID say 'crazy'...)
They act out their little skits (which they practice endlessly) and have a good laugh at their confused ADAM-addled victims, and run away before the victims realize (or use it as a distraction to mug them).
This is a much better explanation than the aforementioned impossible genetic vector (transmitted via recycled ADAM), or some metaphysical alternative (or interdimensional time portal or whatever).
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