James Hedberg

Electroencephalography – or a lot of little wires near my brain

August 28th, 2010 by

So, I let my noggin get hooked up to an EEG machine the other day. Despite the slight discomfort from the chin strap and the repetitive task I had to perform, it was mostly a fun time. I think my next at-home project will be to try to build one of these things. It doesn’t look terribly complicated, just a few wires, electrodes, and some sensitive electronics. Also, based on the setup this particular lab was using, it seems like there’s a lot of room for improvement, from an instrumentation stand point. (e.g. they’re using ribbon wires to carry the signal from the head to the pre-amps, about 2 meters away, a very poor setup for trying to measure tiny signals. Not to mention the CRT display just a few feet from the electrodes.)  Nonetheless, it’s pretty damn cool to see the little lines on the screen dance around in response to the goings-on in the mind. During one experiment, I tried thinking about tigers the whole time, per the recommendation of my friend Jacob, when he was still a scientist. It’s not clear if it’ll disrupt their data, but I’m pretty sure it wasn’t one of the control variables in the experimental design.