A few weeks ago I was presented with a new opportunity for which I had no previous inclination to participate in. A friend of mine currently assisting with MRI research at the UofA was in need of a volunteer willing to subject their brain to a scan. For most people, the prospect of laying motionless in a large metal tube from anywhere between 34 to 62 minutes does not hold any appeal, unless of course this event means the difference between life and death. For me, however, this would be yet another strange and baffling experience allotted to me because of the fantastic group of people I choose to surround myself with.* I have recently been working with the musical acoustics concepts of convolution reverb and impulse response, and I was interested in the possibility of MRI technology operating in a similar way, using imperceptible magnetic waves rather than audible sound waves. I would soon be pleasantly surprised.
My friend (who shall remain nameless) guided me to the MR lab in the basement of the University Hospital, a space strangely reminiscent of the vast hallways contained within the U.S.S Starship Enterprise. At the end of this maze there is a 3 walled room, an enclave where we could change into scrubs and wait. After changing out of my metal-filled clothes, a beautiful red-headed P.H.D. student greeted me with various waiver forms. I was asked a multitude of questions about any metal I might still have on my person. One of these questions involved any ‘unseen’ piercings — this gave me a bit of a startle and made me wonder if the P.H.D. student believed me to be the type to keep pieces of metal in my member. This ferrous question became clear when she explained that even while out of the room the machine would tug at her bra straps. She told me that any metal that was brought into the chamber could potentially become a projectile reaching bullet-like velocity. It was good of her to double-check.
I had heard tales of the visceral magnetism of the machine before. My friend had told me that he could feel a presence when he entered the chamber in which the instrument was situated. This prospect excited me, and as we walked towards the experience I readied myself. Unfortunately, for some unknown reason I could not feel this invisible field. I cannot convey how upsetting this was to me.
The machine was quite visually impressive. The large, white, cylindrical body took up a controlling majority of the roughly 10m by 10m room**. The MRI technician greeted me with a smile and a handshake. He explained the procedure: First, I was to lay down on the machine’s bed, where my head would be locked in place while resting on a piece of foam. Absolutely immobilizing my cranium region was a critical necessity. Next, this bed would slide back into the main tube via mechanical actuation. The technician handed me a set of metal-less headphones*** which would allow me to hear the people in the control room. Some sort of hidden monitoring microphone would allow them to hear me. Aside from the stationary nature of my head, this part of the whole experience was reminiscent of past studio experiences.
The technician also handed me a pair of industrial orange-and-yellow earplugs. The moment I received those earplugs I was struck with apprehension. This machine would be loud. All the previous instances of loud machinery I have encountered warned me of the toxic sound which I believed would soon befall my precious sound detection organs. To hell with it, I came for the full experience.
The sounds made by this machine were not atrocious as I had anticipated, but instead were reminiscent of Portishead like synth-tones. Allow me to relate to you the experience as I remember it:
Imagine sliding slowly back into a large tube with an inner circumference slightly larger than the girth of a small horse. Your head is locked into place and despite there being enough light to see in front of your face, there is literally only the plastic piece holding your head in place to look at. You are currently resting your arms across your chest because if you let them hang loose beside you they would drag along the inside of the tube. This slow moving craft comes to a stop and you can now rest your arms on the tube. For a minute or so you sit, fully aware of any minute stimulation of your senses, like an imperfect sensory depravation tank. An eternity or a moment passes and suddenly you hear a voice over the headphones. It is faint at first but quite clear, it says: “Are you ready to begin?” After confirmation of this request you hear three quiet buzzes, sound coming from above your head, and then a pause. You are given just enough time to contemplate whether or not these buzzes represented the maximum volume of the machine and then suddenly your body is immersed in bass-tones with large amounts of harmonic content. The sound seems all-encompassing, but as you regain your wits it becomes apparent that the noise is more heavily oriented on your right side. Your right arm vibrates as it touches the side of the tube. The first tone bath is quite short and when it finishes you hear a faint echo on your left side; a call-response crosstalk with your body in-between. After this time of silence you are once more alerted via the headphones and the next wave begins. This time the burst begins and holds, changing frequencies at some points. As you listen to this continuous-wave, you wonder if there are minute frequency changes caused by the machine or that maybe your brain is listening to the noise and attempting to find a pattern — are these even that different? Then silence, headphone-confirmation, and tones again, this time pulsing on and off as if the volume was modulated by a square wave. Classic audio synthesis.
This procedure continues for some amount of time. When you are in the tube there is absolutely no reference for time. Each iteration comes with similar sounds but slightly different durations and tones. But all things come to an end. I was rolled out on the platform, unstrapped, and allowed to get up. Standing there, awaiting me were my friend, the technician, and the PHD student. “How was it?”, remarked my friend, and my response was an explosion of blabble about audio synthesis. My friend, a proponent of and active participant in sound synthesis, understands. We are kindred spirits made even more apparent by the PHD student’s comment, “Oh yeah, you’re both musicians,” she said, with a mere scientific understanding of my profound musical aesthetic experience.
It is you dear readers, my proxy-friends, who I believe will also relish the description I give. I only wish I could give you the experience instead of describing it (a hopeless exercise in futility, or a futile exercise with no hope). Most people do not get to go into one of these machines without nervousness, since it is often used to scan for possible tumors or damage to the brain. I am left with the sense that I have done you justice with this account of my very unique circumstance.
- S. A. Bjørn, Doctor of Metaphysics in the United States of America
*note: If you want interesting experiences you need interesting friends in your life. If you do not have any I strongly suggest you go out and find some. Suggested locations for search: libraries, ambient noise shows, and the university faculties which interest you.
**note: this is an unverifiable approximation based on my memory of the place. I have never been good at guessing size, distance, or time so please do not fault me if you know the true dimensions of the space.
***note: these headphones, used to communicate with me while in the machine, consist of a regular style of headband and earmuffs but lacked the internal speaker mechanisms of your everyday close-proximity loudspeakers.