I remember some times when I’d be up for a long time, eventually it felt like the part of my brain that controlled awareness of another person’s presence would glitch out. Like if I was alone in my room playing video games, I’d get a sense that it was time to pass the controller when I died, or to comment on something for the other person that wasn’t really there.

But I was alone in my room, which made it pretty easy to recognize what was going on as a form of hallucination (I’d also see dark spots moving around in my peripheral, which I suspect some less self-aware people might think are bugs moving around at the edge of their vision). If I was out walking, where it was harder to logically be sure that you’re alone when your senses lie to you, I could see it developing into a strong paranoia. Would suck for that to be a normal feeling rather than something that happens after staying up way too long.