honestrosewater said:
Anyway, how was it? Did you learn anything?
It was OK. I don't have any fear of enclosed spaces, but I was still a bit uncomfortable and anxious to slide into that very small MRI space strapped down and everything. But that went away pretty quickly.
Subjectively, the most interesting thing was the noises made by the fMRI machine. First of all, it's quite loud, and they had me put in earplugs before going in. There's a perpetual, rhythmic banging kind of noise that the experimenter joked would make a good techno beat. (I guess that noise is related to the generation of the magnetic field.) Then whenever they scan your brain while you're doing some task, there's an additional noise whose sound I've mostly forgotten by now-- I think it was kind of whiney and droning.
Finally there was a third kind of noise that occurred when they were doing the structural scan (which is what generated the pictures I've posted here). That was the really interesting one. It was a periodic droning electronic kind of noise (lasting about 3 or 4 seconds I'd say) that steadily rose in pitch, from deep to fairly high, before pausing briefly and beginning all over again. It was very trancey. There was something like 10 or 15 minutes of this. As time went on, the bursts of trancey noise rose in pitch earlier in their lifespans-- I'm guessing this was because they were doing their axial scans one by one, starting from about my chin and moving up, so the spatial source of the noise was changing with respect to my ears. Anyway, what was interesting to me about this was that if I chose to focus my attention on the trancey drones, they would actually sound different than if I paid them no particular attention. In particular, towards the end of each cycle, if I paid attention, I heard what seemed like mildly hallucinatory dancings and phrasings and echos playing off from the actual noises. (Don't know if that makes sense, it's hard to explain.) I wonder what the cause was-- I wonder if something about the magnetic field or radio waves in my immediate environment was having some subtle effect on the activity of my auditory neurons. Or then again maybe it's nothing that exotic, but it's still strange.
Yes, that structural scan was pretty trancey with the droning tones and the perpetual beat of the MRI machine floating in the background. I was also instructed during this time to stay still and keep my mind free of thoughts, and I was in that enclosed space where the only thing I could see (via a mirror) was what was projected onto a screen, which during this time was someone's laptop computer desktop image of huge bright yellow flowers against a deep blue clear sky, a kind of exaggeratedly calm and almost trippy image in its own right. So with all that going on I did get into a bit of a zone.
As for the experiment itself, nothing too special there. I was shown a series of images, some of them of negative emotional valence and some neutral, and after viewing each image I rated how aroused I felt on a scale of 1 to 5, and also how 'bad' I felt, from 1 to 5. Before each image I saw one of three cues which told me what to expect. One meant "neutral image coming up," one meant "negative image coming up-- just react naturally" and one meant "negative image coming up-- reinterpret the image so it doesn't seem negative." The reinterpretation consisted of things like "oh, those are just actors, that's not a real situation" or "OK, he's hurt, but he's about to get medical attention and he'll be fine." I was free to make up whatever interpretation I wanted, though the experimenter went over some strategies with me beforehand.
There wasn't really much to be learned for me from the experiment. The main thing I guess they were looking for was to see what brain regions mediate negative emotional reactions and particularly, what brain regions mediate cognitive inhibition of or coping with negative emotional reactions. That's stuff to be learned from the brain scan in conjunction with the data of my responses. I don't think it's too informative if you just look at the behavioral components.
