July 2, 2018 Issue

What’s it like to undergo a brain scan while being burned, poked, prodded, and electrically shocked? Nicola Twilley’s absorbing “Seeing Pain,” in this week’s issue, tells us, and a marvellous bit of medical technology springs to life:

During the next couple of hours, I had needles repeatedly stuck into my ankle and the fleshy part of my calf. A hot-water bottle applied to my capsaicin patch inflicted the perceptual equivalent of a third-degree burn, after which a cooling pack placed on the same spot brought tear-inducing relief. Each time Tracey and her team prepared to observe a new slice of my brain, the machine beeped, and a small screen in front of my face flashed the word “Ready” in white lettering on a black background. After each assault, I was asked to rate my pain on a scale of 0 to 10.

Pain is notoriously indescribable. Twilley’s piece is about a neuroscientist, Irene Tracey, who uses a technique called functional magnetic resonance imaging (fMRI) to produce “blob maps.” Twilley writes, “Watching a succession of fiery-orange jellyfish flaring up in my skull, she had seen my pain wax and wane, its outlines shifting as mild discomfort became nearly unbearable agony.”

Twilley’s prose is clear and concrete. I relish her descriptions:

As the cryogenic units responsible for cooling the machine’s superconducting magnet clicked on and off in a syncopated rhythm, the imaging technician warned me that, once he slid me inside, I might feel dizzy, see flashing lights, or experience a metallic taste in my mouth. 

Near the end of her piece, she writes,

Over the phone, Segerdahl talked me through my scans. “That map is actually really difficult to make sense of,” he said. “Your brain is really, really, really lit up—there’s just a lot going on.” But then he showed me a sequence of images that had been processed in such a way that the color coding appeared only in regions that had elevated blood flow while I endured the prolonged pain of the capsaicin cream. The characteristic pattern of pain began to emerge, and Segerdahl recited the names of the active regions like old friends.

That last sentence is inspired. Strange to say, even though it’s about pain, I enjoyed “Seeing Pain” immensely.