>>12558834(cont.)
One interesting feature of this memory is that because it succesfully passed all the sensory filters and preprocessing it's always considered "true" and never doubted, on the contrary, your brain actively works to complement, repair or ignore any vague or inconsistent data there. When you're awake and sensory data flows like normal this works great filling the inherent gaps in it, but when the sensory input and most brain processes shut down during the sleep the area becomes filled with semi-random noise based on memories and subtle remnants or impressions that are normally drowned out by stronger real signals during the day. Naturally, this leads to dreams, while still following some sort of continuity and having varying amount of details depending on your lucidity, still often being nonsensical, having weird time flow (since you don't actually experience events but rather randomly acquire the memories of experiencing them, time skips included), and you taking all of it as perfectly normal until you wake up and try to analyze it consciously. It's when you realize that the plot jumped all over the place, the places you've been in are randomly pieced together from real world and imagined parts, and people you felt really close to or were familiar with were actually more like "that person" placeholders with little actual detail. It's also the reason why dreams fade away fast after waking up: your short-term memory gets flushed with stronger real input replacing remnants of the dream, and you have to actively remember (copy to long-term memory) or write it down to be able to recollect it later.