Bare with me here.
One particular night during sleep, I, at some point, went into a coughing fit and then resumed sleeping. Or at least I think I did.
During the cough, I thought it might've been the first of many symptoms of a brand-new cold (I had that substance in my throat that I couldn't get rid of, no matter how much I coughed). But when I woke up next morning, there no was evidence of sickness. I then figured I just swallowed saliva the wrong way. I also remembered sounds, like my mother calling me, but failed to remember waking up at any point at all. So...what happened?
I read an article in some nature/science magazine that started with the question "Have you ever with certainty remembered something that never happened?" I immediately thought of "The Matrix".
Anyway, the article talked about some neuroscientists who were conducting tests to thicken the line between real recollections and made up ones.
They tested two cranial lobes: the medial-temporal, which takes in details, and the fronto-parietal, which gathers the gist of things.
They gave two test subjects one sheet of paper with a list of words they were obligated to remember. They then took that away and gave them a second sheet with a slightly altered list (some words were replaced). They were to point out the words they remembered seeing from the first list.
When trying to recall words they did not see to begin with (and affirming that they remember them), the frontal-parietal lobe registered the most seismic activity.
My hypothesis would be that the brain, when trying to recall a perception, mostly looks for the things that fit in with the general picture of it, and will settle for those things even when they're incorrect. Memories are questionable, even when they're expressed by a person who first starts with "I remember like it was yesterday....."
The human brain: the first and last frontiers in historical truth-altering process.
Did my brain generally recall the sleep and randomly put in the vision of myself coughing and my mother calling? If so, then we are entering Carl Jung's territory, and can only come to an answer by knowing the unique language of the sub-conscious.
Perhaps a great memory has the frontal part sharpened a little and the medial part dulled a little, to perceive things optimally. But however fine tuned the mind is, it is still finite, and the objective truth, thus, is still lost.