How can a Pure Titans recover the full body after extended period?


It is said that Ymir spent about 60 years in Pure Titan form. It is also said
that Pure Titan only have original subject's spine instead of full body like
one of Nine ([see ref [25] here or search word "spine" if number
shifts](https://attackontitan.fandom.com/wiki/Titan)).

So, how exactly she could recover back to complete human with brain,
conciousness and memories while turning into one of Nine? Other
transformations explicitly shown or mentioned so far generally only take less
than hour between turning human into Pure and upgrading to Nine, so it less of
a concern, but 60 years? Shouldn't pretty much of whatever was original Ymir
be long lost by then?




**That is outdated information.** It was revealed later on in the series that
Pure Titans are humans who transformed into Titans. _They were not absorbed,
they transformed, notice the difference_. Their body parts, brain and all,
just got bigger. Their transformation to pure Titans, however, limit their
ability to think although it does not mean that it completely eradicates their
brain. If I were to speculate, I believe something in their transformation
causes a part of their brain to be 'locked out' and can only be accessed once
they consume another Titan Shifter.

Official information about this from the manga, though, is yet to be revealed.
But what we do know is that _Titans have regeneration abilities and
immortality_. **So, no, the original Ymir would not be long lost by then.**

