Thursday, July 24, 2014

Another EEG

Josh Rasmussen encouraged me to run the toy EEG while I was writing book chapter, presumably as a way to get me to make more progress on our joint book arguing for a necessary being.  So, here it is.

Looks to me slightly intermediate between the graphs for blogging and for feeding in the earlier EEGs.

The topic of the chapter is the same as that of the post I was doing in the earlier EEG.

In case anybody is curious, here's how raw data (not from the above, just from some software testing I was doing) looks like.


Amusingly, one can also touch the electrode to one's chest, put one's fingers in the ear clips, and get an ECG.  I think I got my $21 worth of fun. :-)

6 comments:

William said...

It's very amazing how they have gotten $10,000 or more costs of such equipment down to the pricing they have. It does require some short cuts, but nice stuff nevertheless.

Looking at the tracings, I think they all show normal wakefulness, and the main differentiating factor is the type and frequency of eye movements.

The only way to prove that would be with the raw data, and the device does signal averaging in the hardware, so you have no access to such. Fun though.

Alexander R Pruss said...

Actually, the EEG chip does provide optional access to raw data every 2ms. Unfortunately, the device (coincidentally called the BrainLink) I use for bridging between the PC and the EEG chip can't handle the data flow for that.

I just modified the BrainLink firmware for greater throughput. I can now get raw data approximately every 10 ms or so (not the full resolution provided by the MindFlex, alas). The bottleneck is now my singlethreaded java code for displaying it.

Alexander R Pruss said...

I can capture raw data at close to full speed now, though I can't display it at full speed.

Alexander R Pruss said...

All my code, by the way, is here: https://github.com/arpruss/

Dagmara Lizlovs said...

All this makes me think of is that commercial I used to see on TV with the frying pan and the egg - "This is your brain. This is your brain on drugs..."

Here's my take - "This is your brain. This is your brain on deep thought..." :-)

Alexander R Pruss said...

Or at least on rapid scanning of text.