My Brain on Magnets
by Mark Derewicz
(filed under: health & medicine)
The MRI technician looks at my chart and says, “You worked at a woodshop for a few months; did you work with metal?”
“Um, I don’t think so,” I tell her.
“The reason I ask is because this MRI machine is really just a huge magnet,” she says. “If you have a tiny piece of metal in your eye that floated in from someone grinding metal, then the magnet could move it around” — she waves her hand wildly — “and cut your optic nerve.”
Now I’m scared. I don’t recall bits of metal floating into my eye socket, but I don’t remember a lot from my woodworking days.
I’m at UNC’s Magnetic Resonance Imaging Research Center because I thought I might like to write about being part of a research study, and I needed the $185.
This particular study is for bipolar depression. As far as I know, I’m part of the control group. I’ll have three neuropsych exams, and researchers will take pictures of my brain three times over the course of sixteen weeks. I’ve never had an MRI, but the internet says it’s safe.
When I decide I have no metal in my head, the technician gives me earplugs and headphones, and she attaches a plastic cage around my head. The cage has a mirror, so I can look down the MRI tube and watch the U2 concert DVD I brought along.
She slides me in. There are three inches between my face and the top wall; I feel my hot breath tumbling back on me.
The machine pounds away like an electronic jackhammer, a wall of noise with some funky rhythm and muffled melodies. But I can see Bono clear as day, from his silly sunglasses down to his platform shoes.
A good hour in, an awful knocking sound jolts me and I feel like I’m riding an old washing machine. Not too long after, just as U2 strikes their last chord, the jackhammer stops. The crowd goes wild and I’m set free. And I can still see.
I ask the tech if some people can’t stay in that claustrophobic trap.
“Some try and can’t do it,” she says. “Some squirm around so much that the brain scans are blurry and useless.”
And if the photos are blurry, or people can’t stand the narrow tube, then their neuropsych exams are useless and researchers have to recruit more people.
Those MRIs and neuropsych tests help psychologists create a baseline for how a typical person’s brain works. In one test I have to name as many animals as I can. In another, the research assistant rattles off fifteen words that I have to repeat. I long for the giant magnet, with or without U2.
I ask the assistant if some people circle true or false on the test without reading the questions.
“Yeah, that happens,” she tells me. “That’s why I’m sitting here with you. One guy fell asleep. Some people clearly don’t care. We have to weed them out so their results don’t screw up the study.”
I continue to answer — yes, I’ve been depressed; no, not for months at a time. I plod along for three hours, and I wonder: do I need the money this badly?
Maybe not, but the researchers seem to need me — so long as I don’t have metal in my head.
