Open Solutions For EEG, Biofeedback Hardware?

peko asks: "Does anyone have some experience with free/open solutions for eeg/biofeedback gizmos - especially for the PC. I dream about low cost solution for something like: Procomp & Biograph, Bionetica, Neuroscan, Loreta, and ThoughtForm. "

Comments

a continuation...

[^_^x]

Here it is!
http://www.vm3.com/MotionWare/option01.html
Motionware... and they plan on making them under $100. Sure it sounds like vaporware potential, but if it comes out, I'm getting one.

Here's a low cost neuromapping tool called the Mindset.
http://www.aquathought.com/mindset.html
-An Open Standard-
Mindset is based on a completely open software architecture.
Through ActiveX, third-party developers and end users have
unlimited access to extend or customize Mindset. In addition,
the Mindset data record format is an open and published
standard.

...ah, now if only Ono-Sendai hadn't gone out of business...
(Sega VR HMD, sourceless orientation sensor... went bankrupt.)
This link is as close as I can get to finding the original company history.
http://www.hyperreal.org/~mpesce/vitae.html

Open/Homebrew EEG/Biofeedback...

[cr0sh]

I think the MotionWare has turned out to be vaporware - it has been in the "about to be released" mode for about two or more years now (I remember them posting in the hombrew VR mailing list, back when it had real activity, asking if anyone wanted to buy dev/beta units for a grand or so). Not that the tech doesn't work in some regard - they have a patent on the tech, and it is on the IBM patent server (I am not sure if this is the patent, but it is very similar) - just go to the server, and look up the words "vestibular stimulation" - there are other patents available as well.

I also remember an old Ciarcia's Circuit Cellar article in an old issue of Byte magazine - late 70s/early 80s, IIRC - that dealt with building your own EEG machine. What I distinctly remember about the article was that the devices used for amplifying the brain's output, were special op-amps, with extreme isolation and extra-high amplification, with low noise. I remember that he wrote that the op-amps were expensive, around $50.00 a piece (and considering the time, that was damn expensive for a chip). The biggest concern was the isolation (of the skin contact vs. current in the system - essentially to keep you from being electrocuted in any manner), which these special op-amps were designed for. However...

It may be possible to homebrew the sucker using some standard op-amps, set up to perform infinite amplification (by eliminating the feedback resistor), and cascading them (2 or three, via caps probably). Get the sensor pads and gel from a medical supply house (or you might be able to build your own in some way). The problem is that you won't be isolated whatsoever from any current in the system - run the thing off of batteries (this probably won't help much, but it is better than even thinking about using a wall wart). Build a couple, and hook the outputs of the amps into a couple of high performance A/D convertor chips (16 or 24 bits should be enough res - actually, maybe you could use a high end sound card via the analog line-in/mic-in ports).

The output will be noisy as hell - time to write some code (probably a ton of FFT shit here - you will be in for a ride if you get this far) to pick out the details from the noise. If you do get meaningful output, then you just have to figure out what to DO with it (which is pretty much where everyone else is at).

So yeah, it is possible to homebrew it, but it won't be easy - or cheap.