This remarkably well describes my experiences with mushrooms. I recall all of it, its not some brain fog like from alcohol or weed, but those experiences perceived by massively 'expanded' brain simply are not the same as when remembering it sober, its like seeing a tiny crop of an original picture, it may still make some sense but you are probably missing most of what actually happened.
But let me tell you, once I got into another trip, those memories from previous trip again made complete sense and they were very detailed, if only for that brief amount of time.
Anyway back to the topic, when tripping (alone, laying in bed with eyes closed, shamanic music in background, late evening), I felt I gradually lost all my senses (ie weird to keep 'seeing' as experiencing what was happening, yet organ of the eyeball was unreachable at that moment to my brain, and so were the others), all connection to my body. Heart rate went to very low mode (I held breath for what I referenced as few mins just to try this new situation, not more than 3, and I could 100% control all feedback from desperate body spasming for any air while I was casually observing it, not a worry in the world for that experiment - just to clarify I don't do any freediving or similar activity where you train to hold your breath). At the height I was a mist of atoms, dancing or more like swirling in the air in the music, nothing in nothingness. Those atoms were tiny parts of me, alone useless and incoherent, meaningless.
And once trip was ending, very very gradually (I'd say it alone took 90 min easily), coming down from that peak one step at a time, re-discovering senses and body. All those atoms joining one by one. I felt very strongly that if I had any major character flaw or unresolved issues, this would be the moment where putting back those atoms wouldn't work very well.
I had this without getting any info from more experienced users or research (those mushrooms I grew myself from growkit from Amsterdam, we talk about cca 2007), and the part about splitting into atoms and then combining them back together sounds similar to neuroplasticity you describe.
Just for the love of god don't do such strong stuff if you have some unresolved inner issues. There is a chance you can solve it for good via this, but the risk of something going wrong and ending up in catatonic nightmare, or even some (additional) permanent damage ain't worth it. If it would be long term legal and accepted and you would be able to have professional managing the set then this part should be without major worries.