Many times, in fact. One of the experiences sticks with me.
I remember it in patches.
They stuck me inside a magnetic resonance imaging scanner–MRI for short. It’s like a big sarcophagus made of metal and plastic. You lay on your back in the dark while a loud hammering noise does semi-circles over your head from left to right and back again, over and over like one of those rotary lawn sprinklers: slow in one direction, fast in the other direction. It’s so loud they have to give you over-ear headphones to protect your eardrums; the headphones double as a communication device. They talk to you through that, and a microphone over your mouth allows you to talk back. Essentially, an MRI scanner takes pictures of your brain by surrounding it with a magnetic field and registering the electromagnetic response. If the technicians are nice, they let you look at your brain pictures when it’s all over.
While I was being scanned, they sedated me with ketamine–yes, the mild hallucinogen ketamine–“Special K” when called by its street name–until I was about, oh, I don’t know, 1% conscious. They allegedly told me a story through the headphones. They brought me out of consciousness until I was about 75% cognizant of my surroundings. While I lay there in the dark, they asked if I remembered anything. I couldn’t recall much of anything, and told them so.
Boom, they sedated me again, a bit less this time. I was about 15% conscious, or so it seemed. Allegedly they told me the same story as before. When they brought me back to about 75% consciousness they asked me if I remembered anything about the story this time. I vaguely recalled some girl by a river with a bridge. And there was a troll. And there was a room, and a boy–some boy–and someone was looking for something, and people were standing in a certain geometrical relationship. And I vaguely recalled the girl having red hair. Or did I make that up? It was a distinct impression, at the very least. The red hair felt real, either by their telling or by my imagining.
They brought me fully out of sedation and told me the story for the third and final time. When they asked me if I remembered anything about the story, I told it to them from beginning to end with total accuracy. I won’t bore you with the details.
They extracted me from the MRI scanner and wheel-chaired me into another room to dry out. A researcher asked about my overall impression of the experience. She seemed really excited about the whole thing. Her face lit up every time I opened my mouth. She made me feel as though my words were important, which encouraged me to speak at length about every last detail. Kudos to her for that.
One interesting side effect during this experience was that at one point I distinctly recall scientists in white lab coats walking around behind me while I was in the MRI scanner. My brain totally made that up. The MRI is sealed on all sides except where your feet are, for one. Secondly, no one was wearing a white lab coat before or after I entered the scanner.
No, there are no lasting effects. Except aliens. I am always surrounded by aliens in pink tutus and they all want to sell me a vegan hamburger. It’s cool though. I just play my ukelele louder until the aliens retreat to a far corner to shoot craps for a while.