Had an MRI and it fucked with me a bit more than I had thought it would. First off the technician said the MRI should be only around 25 minutes, but when in the actual machine there wasn't a way to figure out how much time is passing. Luckily the fact that the sounds the machine was making wasn't constant which at first startled me, ended up being a very useful distraction. It was pretty much the only sense that was getting stimulated and I latched onto it hard. It would have variable frequency, variable speed, repeat for variable number of times while slowly modulating a variable amount before a variable amount of 'silence'. Where silence being the standard still pretty loud background noise. And so I grouped the patterns of sounds into blocks based off of 'silent' intervals, can estimated that to a certain amount of time per block, and estimated that 25 minutes should be around ten such blocks. Counted down the blocks from ten until it reached negative four when I was pulled out. At that point the technician gave me a board to hold over my chest and said ten more minutes. I was in a bit of disbelief. That was only fifteen minutes? It felt like forty five! So in I went into the machine again for another indeterminable length of time. Not as long as the first time, but more than 1/2 as long at least. He pulls me out of the tube on more time to take away the board, and in I go again. By that time I was completely zoned out just listening to the noise wishing it was over, questioning time and reality it self. How could all of this be only twenty five minutes? When it was finally over and I was away from the loud sound, everything felt really quite. Eventually I got back to my stuff. and needless to say I wasn't in the MRI room for ~25 minutes, but closer to an hour and five minutes. Worst part of an MRI? Claustrophobia? No. Loud Noise? No. Sensory deprivation.