Well… if time didn’t exist in heaven, I would answer yes.
But the issue is that Heaven has two aspects as a “state” and a “place”.
Places, which are creations, and are subject to change or bringing into existence are not completely outside of time – for context see eg: Revelation 21:1
So: I will answer that God, himself, is outside of time – BUT the incarnate Son, who is a creature in hypostatic union with the divine Son (God); that person was and is not entirely outside of time but able to move freely within time, and outside of it.
For example, Jesus as a boy who was & is in perfect union with the Divine Son, could “learn”, he grew in wisdom while on earth ( Luke 2:52 ) even though the Son was already omniscient whenever decided to access that omniscience.
Something else which I am not going to explain, but just mention is that where & when heaven is concerned; Jesus says something very peculiar: Matthew 24:36, Mark 13:32, etc.
Also, back to the subject of “forgetting your past life” and what-not, wouldn’t it not make complete sense to say that human souls forget their life’s journey completely? Heck, the saints are often dedicated as the patron saints of so-and-so (doctors, throat-related illness, anxiety, and whatever else). I doubt the saints would be like, “Wait, what does so-and-so have to do with me?” because they forgot what made them the patron saint of that particular thing in the first place. Right?
Well, I’ll admit we’re in a bit of difficulty.
The resurrection hasn’t happened yet, temporally. So, there is the issue you seem to be commenting on, vis: that the saints do not have a body with a hipocampus in it yet… and St. Thomas Aquinas theorizes that such a separation between body and spirit is a temporary punishment brought about by original sin. However, I need to say I’m not a Thomist, though I do respect his opinions and consider them. St. Thomas’ explanation has always bothered me, because no one (except Mary and Jesus) has a body in heaven, yet; even if they are declared saints, immediately in heaven, by the church.
So, it would appear – that given the Dogma of the bodily resurrection at ‘the end of time’ – that all saints must suffer the temporary loss of their body.
I’m not sure what to tell you – although we could explore the scriptural roots of the question; I’m not well prepared for it at the moment.
However, there is at least a partial answer in the fact that all these saints are in communion with someone who does have a body (Jesus), and therefore, through the actions of the Holy Spirit (The sap, between the vine and the branches), anything Jesus has can be communicated to the saints you are speaking of. eg: His memory, or his views of time, can be selectively presented to their intellect / spiritual souls.
We have examples of the divine ability to bring things to mind – either that which could be remembered of the past – or which could not of the future.
eg: John 14:26, “So much converse I have held with you, still at your side. He who is to befriend you, the Holy Spirit, whom the Father will send on my account, will in his turn make everything plain, and recall to your minds everything I have said to you.” or again, regarding future knowledge, even:
John 16:12-15; “I have many things to say to you, but you can not bear them now.”
It’s important to notice that we have been talking about episodic memory. The memory of one’s past events as a sequence of events (There are other kinds of memory). So, I’d like to point out regarding saints knowing who they were, that intellect is capable of recognizing one’s self in a movie, even if the actual memory of those events does not exist. eg: I have seen myself as a child in films from my parents which I don’t recall the events – but I DO recognize myself in those movies. I am able to figure out who represents ‘me’ in that movie.
Just so, I don’t see that its a problem for a saint to know who they were if God supplies them sufficient clues to replace their lost memory.