The true nature of human sleep patterns — a species that, as far as the emotions could tell, Riley belonged to — was helplessly concealed, at least for humans themselves, by the frequency at which Mental Notes, the building blocks for memories, came in. It was very easy to see, from an emotion's perspective: lots of Mental Notes came in during the day, none came in during most of the night, and only a handful came in during the part of the night when dreams happened.
Thus, when humans talked to each other about dreams, a variation on the idea was exactly how they approached the subject. To them, all of the night, or at least a vast majority of the night, was taken up by dreams, and those dreams definitely felt only as long as a fraction of the actual night. After all, that's what the night felt like: falling asleep, the dream, and then, waking up, with a significant break in perception. There was no way that it could be anything else.
Yet, it was all a thick veil of lies concocted by the interplay of Imagination and Consciousness, and the emotions were in the mostly-unique position of knowing the truth — if you disregarded Dream Theatrical Studios, the department of the mind responsible for dreams, for a moment. If you asked an emotion, they would tell you that dreams only took up small portions of the sleep, in a phase known as Rapid Eye Movement, or REM for short. The other phase, often called "deep sleep", would have no dreams at all. These two phases came in cycles of roughly 90 minutes, with the deep sleep coming first and the REM sleep taking up the rest in a cycle, and in each successive cycle, the REM phase would be ever-so-slightly longer.
Luckily, humans, at least those studying neuroscience, were finally starting to catch onto the truth that the emotions had known all this time. This was why Joy could think of the two distinct phases as "deep sleep" and "REM"; those were the accepted scientific terms. Yet, it still frustrated Joy to no end; there was an absolute wealth of knowledge to be unlocked by simply giving the mind a cursory glance, and it was all out of reach for humans. Perhaps emotions living inside other humans shared the frustration; however, there was no way that Joy could have known.
In fact, for Riley's emotions, there was no real way to be sure that the people around her even had emotions and minds like the one they lived in. Sure, those people treated Riley as one of their own, and they looked to be dealing with the same sort of problems and having the same sort of reactions as Riley. Yet, Riley's emotions still couldn't know. Perhaps the world seen through the Consciousness Screen didn't exist at all, and was more like an elaborate video game: once the "GAME OVER" screen appeared, the emotions would be free to live out the rest of their lives, being relieved from their duties.
The thought was a bit exciting, Joy had to admit. If the outside world didn't exist and didn't matter at all, then it would basically be indistinguishable from a video game. Riley, the emotions' player character, would be little more than a blank slate for the emotions to project themselves onto, and the console would be like an intricate controller allowing for the most minute control of her actions. And, given that there weren't any real rules or repercussions for breaking them, the sky was the limit.
However, given what the atmosphere in the supposed game was around, it was for the best to assume that it was all real. Riley was an actual teenager with actual parents, actual friends, and an actual home. Though the actual home was rather unusual for an American, the actual parents were incredibly supportive, the actual friends were great fun, and Riley's life, in general, was good.
Yet, dreams were these pesky little things that challenged all of those presumptions. In a dream, an emotion could be made to forget everything they knew about their host, and instead be forced to play along with the rules set forward by Dream Theatrical Studios, which were simply not the same from night to night. If they wanted, they could bring forward a quite heartwarming dream, in which Riley could breathe underwater. However, the next night, the vast expanses of water would become the setting of a nightmare, in which Riley would be in a perpetual state of suffocation, with the pain never stopping.

YOU ARE READING
Inside Out reImagined
FanfictionSmack dab in the middle of puberty, Riley Andersen often feels as though she can't control herself. To one's surprise, though, five emotions inside her mind think very much the same; they just can't pull their girl's strings like they used to. As lu...