fMRI: A Few Cardinal Rules

There are a few cardinal rules of brain scanning, using fMRI.  Foremost, because the scanner is a strong magnet that can draw in a piece of metal from across a room, damaging the machine and anything in it’s path (including people), no one is allowed to enter the scanning room with nickels, dimes or quarters in their pockets or any kind of metal on their heads or body.  Tooth fillings are fine.  But pace-makers, intra-uterine devices, jewelry, the underwire of a bra, belt buckles, credit cards, lip and face decorations and other metal accessories: all must be removed.  Many of these are well anchored, of course.   But they are likely to tug uncomfortably, as well as interfere with data collection.

Claustrophobic people aren’t happy in the scanner.   The scanner is snug--a long, slim donut hole in the middle of a huge machine.  Even if a claustrophobic individual forces him/herself to lie inside this tube, their fear can alter brain circuits and skew our results.  Those taking any kind of antidepressant aren’t candidates either, as these drugs change activity in the brain regions we are studying.

Moreover, participants must remain motionless; the slightest movement of the head will alter our data.  So Helen goes to great lengths to make a subject comfortable, offering pillows under the knees to relax the back, a blanket, earplugs to soften the bizarre groaning noises of the machine, and spongy padding around the head to help the person keep it still.

Then, when the participant is settled comfortably on the gurney just outside the machine, we suspend a mirror over their eyes so they can see the images we will show them while in the scanner.

Last, we give them a little rubber bulb to squeeze if they want to get out of the machine at any time.  The experiment will be ruined; but the comfort of the participant must come first.  If squeezed, we get them out immediately—although this has (luckily) never happened in any of our experiments,

For our first study of early-stage intense romantic love, we used a 1.5 Tesla scanner at Stony Brook University in New York.