One particular spirit resented the fact that he could not remember much of what he had known during his physical life. He was grieving over the pleasure he had lost because it had been his chief delight. He was told, though, that he had not lost anything at all and that he knew absolutely everything. In the world where he was now living he was not allowed to retrieve things like that. It should satisfy him that he could now think and talk much better and more perfectly without immersing his rational functioning in dense clouds, in material and physical concerns, the way he had before, in concerns that were useless in the kingdom he had now reached. Now he had whatever he needed for his functioning in eternal life, and there was no other way he could become blessed and happy. So it was the counsel of ignorance to believe that the removal and dormancy of material concerns in the memory led to the disappearance of intelligence, when in fact the more the mind can be led out of the sensory concerns that are proper to the outer person or the body, the more it is raised up to spiritual and heavenly concerns.
In the other life, people are sometimes shown what memories are like by having them presented visually in forms that are merely appearances (many things are presented visually there that for us here are strictly conceptual). The outer memory there looks like a callus, while the inner looks like the medullary substance found in the human brain. This also enables us to recognize their quality.
For people who have focused solely on memorization during their physical lives, without developing their rational ability, their memory has a callused quality that looks hard and streaked with tendons inside. For people who have filled their memories with false notions it looks shaggy because of the random mass of disorganized stuff. For people who have focused on memorization with themselves and the world first in mind, it looks stuck together and bony. For people who have tried to probe divine secrets through acquired information, especially philosophical information, without believing anything before they are convinced by the information, their memory looks dark, with a quality that actually absorbs rays of light and turns them into darkness. For people who have been guileful and hypocrites it looks bony and hard as ebony that reflects light rays.
However, for people who have focused on the good of love and truths of faith, no such callus is visible. This is because their inner memory is transmitting rays of light into their outer memory, and those rays find definition in its objects or concepts as though it were their foundation or their soil, and find congenial vessels there. This is because the outer memory is the outmost element of the design, where spiritual and heavenly matters come gently to rest and dwell when there are good and true contents in it.
from Heaven and Hell, Sections 465, 466