Brain cells that track location in space appear to also count beats in time
If you take enough acid, it can become incredibly difficult to perceive the passage of time with eyes closed. On one of my higher doses, I was in such an uncomfortable state of mental agitation, fetal position under my covers, that I tried killing time by playing a game of pretending hours were passing when I closed my eyes, and I could briefly believe it until an external sound clued me back in.<p>Changes in spatial perception might also explain some mental visions, like truly massive scale structures that are hard to imagine when sober, but those incidents aren&#x27;t as profound on acid in my experience, and you don&#x27;t see them visually. They&#x27;re more high-definition thoughts.