Wednesday, October 8, 2008

Measured In Bowies.. I Mean Teslas



"The tesla (symbol T) is the SI derived unit of magnetic field B (which is also known as "magnetic flux density" and "magnetic induction"). The tesla is equal to one weber per square meter and was defined in 1960[1] in honor of inventor, scientist and electrical engineer Nikola Tesla."


And it's the unit of measurement of strength of an MRI and fMRI. (Although someone recently told me that I have this wrong... apparently there are two different kinds of tesla measurements, and I need to do a bit more research on this. But since I'm not going to be a medical doctor... and this is more out of a general interest for me, I'll leave it at that for now...)
Magnetoencephalography is an imaging technique used to measure the magnetic fields in the brain. And it is really, bloody cool. Imagine wearing a giant helmet full of something called "SQUIDs" (superconducting quantum interference devices), which are basically super-sensitive devices that are sensitive to picking up magnetic fields and someone cancelling out the earth's magnetic pull. The helmet never actually touches your head but kind of hovers between 6 and 12 inches away.


Okay, I totally cop to the fact that as my prof was explaining this stuff to my class, I was imagining I was Magneto. That I was Ian McKellen playing Magneto. And of course, it got me thinking to how we associate famous figures from history and science with the celebrity that played them in somesuch. Someone mentioned teslas, and next thing I knew, I was hippocampus deep in the Thin White Duke. A happy place to be, by all accounts.


It's no secret that nerds and geeks of all walks have long since held up Nikolai Tesla as the epitome of awesomeness. He was a synesthyte!!! He was working on a death ray, people. And honest to god mf DEATH RAY... I don't approve of necessarily using death rays, but I mean COME ON!!! That is mf cool!!! So who else could play this man (in The Prestige - a fair to middlin' movie) stepping into camera shot out of an electrical storm but David Bowie? No one, that's who... When that giant glass eye looked "at" me from the giant screen, I belived he could see my voice as it said "cool as f*ck."


So, my brain is totally in it's happy place when my prof mentions that most MEGs are calibrated(?) to 1.5 teslas, and that there is some controversy about whether or not it is safe for children to be in an MEG of 2 or 3 teslas (the higher the teslas, the sharper the image... not so important for clinicians, but of much use to researchers - I mean think about it... if you can get a kid with ADHD and autism to sit still for 45 minutes, you want a crystal clear image of that brain...) And apparently back in the early 40s, they discovered that leaving someone in an MEG too long (say 4 hours) results in 3rd degree burns. These burns are internal, because essentially, an MEG is like microwaving yourself a bit. It shakes up all the H++ in your oxegen molecules and affects their polarity. Do it for too long and those bonds start to break, creating heat inside the body. Apparently, an hour or two at 1.5 teslas is safe... but we're not quite sure what would happen if we cranked up that sucker to say 3 or 4 Ts (yes, it's lowercase when you spell it out, but uppercase when you use the short form because it's someone's name) and put their poodle in it to dry it out after a rainstorm.


Which confirms scientifically, in the silly little part of my mighty brain, that Ziggy Stardust is smolderingly hot. As if we needed further proof.

4 comments:

LizB said...

Oh my LORD...only you could make science HOT. And distracting. And yummy.

I think it should be measured in "Bowies" too!

And i'm just curious...where was the glass eye in the prestige? If you're talking Bowies' eye itself....it's still real, just damaged. He never LOST the eye, just most of the vision in it.

Nitpickin', i know.

Anonymous said...

You're closer, but not that close. Talk to your Prof, get it right. Even if you're not a scientist, as a psychologist you need to have a good idea of what technology is available to you.

My apologies for being somewhat harsher in my last post (that you deleted).

LizB said...

I am expecting this comment to be deleted myself, but I have to say "anonymous", why not just say WHO you are, instead of hiding behind that wall of anonymity? At least engage, and put a name to the words you are sharing. One is less likely to take you seriously, if you won't even say who you are. Especially when being so vitriolic.

Psyche said...

Hi lizb:

Thanks for your ability to be an effective bystander. I've addressed the issue in another post. I agree that anonymous posting can be a form of "safe aggression," and I won't tolerate any more bad behaviour on my blog. Just as I have something to learn about medical imaging, others have much to learn about basic polite behaviour and citizenship. My hope is that whoever it is, they will take the opportunity to shake hands and be friends. I'm just not the vindictive type!

:)
Thanks again. Bullying does tend to stop when a bystander intervenes!