Well, I was going to write about writing conflict in stories today, but I think I’ll have to put that off for another week because last week I experienced something that I really want to write about—spending two and a half hours in an MRI machine.
I volunteered to be a part of a cognitive research study at a local university, and so I got to spend two and a half hours in an MRI machine getting an fMRI scan. The “f” in fMRI is for functional, and all that means is that they take images of the brain while it is functioning, i.e. while the test subject (in this case, me) is performing some task.
It is because you are doing tasks that you have to be in the machine so long. First they do about twenty minutes of preliminary scans during which you lie still with your eyes closed, then about an hour and a half of scans while you are performing tasks (mental tasks that you “perform” by pushing buttons on a remote control of sorts), followed by another twenty-five minutes of passive scans at the end.
Of course, to do this kind of scan one must not be claustrophobic, as more than two hours in a narrow tube would be anathema to someone who is claustrophobic. Since, thankfully, I’m not claustrophobic, this was not my issue.
But there were two things that did upset me a bit. One was my fault entirely. The other couldn’t have been predicted based on what I knew at the time.
The first thing had to do with metal. MRI stands for Magnetic Resonance Imaging. The images these machines produce come from the radio waves generated by the very powerful magnetic field that is generated when the machine is turned on. A video on iflscience.com, shows some researchers demonstrating just how powerful the magnets are—with one object (an office chair) being pulled by the magnets by 2000 pounds of force. Yikes!
Because the magnetic force is so powerful, it is imperative that any metal that reacts to magnets be removed from the room before the machine is turned on. So no office chairs on wheels and no earrings either (just imagine an earring being ripped from your earlobe!!).
Before you can do the scan there is a huge list of questions you must answer about any potential metal on or in your person that could be affected by the magnetic field. And I answered no to all of them. Though, when I got to the question about dentures, I did ask about crowns (I have a lot of crowns—dumb fillings didn’t last!). They said the crowns would be fine, so I went merrily on my way.
About ten minutes into the first scan, I had started to feel some pressure in my sinuses and then in my jaw. It may have been psychosomatic, but I swear I could feel my molars—the ones with the crowns. Now, it wasn’t painful or even uncomfortable, it was more like an awareness of them that I’d never felt before. And it’s entirely possible it was mere suggestion that made me think I was feeling them. In any case, I suddenly remembered something I had completely forgotten, and I started to panic.
I have a metal post in my mouth from a broken tooth that had to be rebuilt when I was eight years old. I guess because that was about forty years ago, I didn’t think of it earlier. But I thought of it now. I had no idea what could happen (I hadn’t seen the iflscience video yet, thank goodness!), but no idea sounded good. At best the metal would mess up the images, at worst, my front tooth would end up on the ceiling of the MRI machine. So I squeezed the emergency button they gave me and quickly told them about the post, apologizing profusely for forgetting.
But I worried for naught. The MRI technician said it shouldn’t be a problem but to let them know immediately if I felt any discomfort. And I didn’t. Phew! (At least not from that quarter.)
It turns out that there is at least one other way that an MRI machine can make a person feel uncomfortable: nausea.
Right away, after being put into the machine, I started experiencing nausea. It wasn’t too bad at first, just a slight wave of it. It did start to get stronger the longer I was in the machine, but once the tasks started, I was distracted and only noticed during the down time between tasks.
About halfway through the tasks, I became overheated and felt really dehydrated, so I asked to be let out in order to get a drink of water. That’s when I realized just how sick I felt. I felt wobbly on my feet, and had that swirly headed feeling you get from spinning around too long—it reminded me a bit of having “sea legs.”
I was honest with the researchers about how I was feeling, and the technician suggested the nausea might be from looking at the computer screen via the mirrors in the helmet they put over my face. That made some sense, but it didn’t seem right for me, and to be honest, I wasn’t sure I was going to be able to make myself get back in the MRI to finish the tasks. But the researchers were kind enough to let me have as much time as I needed, so I drank my water slowly and chatted with them. They showed me some of the images of my brain, which was really cool!
After about fifteen minutes, I felt better enough to keep going. However, they had to redo the initial passive scan, and about five minutes into that the nausea started again. And I had my eyes closed. So at this point I was pretty sure it wasn’t the helmet that was causing the nausea—though spending more than an hour moving only my eyes back and forth probably wasn’t helping.
Fortunately the tasks started up when they did because I was moments away from squeezing the emergency button again. But the tasks took me away from my physical self well enough that I managed to finish the scans. However, I was again terribly nauseated and wobbly when I was done. And again, I mentioned it to the technician, who this time told me that some people can experience nausea if they have very sensitive inner ears!!
Apparently I have sensitive inner ears.
I did a little looking, to verify what the technician told me (mostly because everyone I told afterwards seemed a bit skeptical that it was the magnets themselves and not my eye movements or the weird viewing angle that caused the sick feelings). And it’s true. A study by Johns Hopkins University researchers found that people can experience vertigo because of the way the magnetic field inside the machine affects the inner ear.
Of course, there was no way to know beforehand that I would react that way, so I’m not sure it would have been helpful to have been warned ahead of time. But I do know one thing: I’m never doing that again if I can help it!
Sources mentioned in this post: