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5.4.13

Colbert gets fake EEG'd

Hot on the heels of the huge push this week about the NIH BRAIN project, Francis Collins, Director of the massive NIH, made an appearance on the always-awesome Colbert Report (which several friends pointed me to).


During the interview Collins has Colbert place an EEG cap on his head and shows off what's supposed to be Colbert's brain's electrical activity.

Except it's clearly not. At least, not really happening live anyway.

I know a thing or two about EEG and over the years I've personally collected EEG data from more than 100 people. I'm willing to give 5:1 odds on the data being shown being pre-recorded (probably not from Colbert).

This isn't a big deal. But I find it amusing because, remember, Collins is the head of an institute that doles out $30.9 billion each year in biomedical research funding and just announced with the White House a huge $100M project specifically geared toward understanding the brain.

And with all that money Collins still can't get good enough tech to do an honest real-time EEG demonstration.

Here's Colbert with the cap on:


See that thing hanging by his eye? That's an external electrode used to record eye movements and to use as a signal reference. Not hooked up. So what's the signal being referenced to? Maybe another electrode?

Here's a data trace:

The big fluctuations behind Colbert's head are visual alpha (see here for a primer on alpha). The high-frequency activity behind Collins (in the lower left) is muscle artifact (probably frontal cortical); remember muscles work off electrical activity, too, and our face muscles are much closed to the EEG electrodes than the brain so muscle activity shows up as a huge artifact in EEG.

In the upper left you can see some lower frequency (maybe 2Hz?) shifts. While I can't see a time-scale, knowing that the activity behind Colbert is about a 10Hz oscillation (because that's what the visual cortex does) gives me a rough time scale. This low-frequency activity tells me the data aren't being filtered below at least 2Hx.

This all tells me several things:
  1. If this were real data, Collins is boring the shit out of Colbert given how high that visual alpha activity is (visual alpha activity increases when someone is drowsy or has their eyes closed).
  2. The data are not being filtered using too low or too high of a bandpass filter, so artifacts like muscle and movement artifacts (high frequency artifacts) and eye movements and blinks (low frequency) should be visible.
  3. The lack of crazy data noise when Colbert turns his head tells me these data aren't real. When you move your head like Colbert the physical movement of the electrodes and wires, along with all the muscles used to move your head, shows up as a huge artifact.
  4. The lack of any eye blinks or movement artifacts picked up by the frontal electrodes (near the eyes) tells me these data aren't real.
Pretty wild what you can infer from a bunch of squiggles once you know what to look for, huh?

9 comments:

  1. Anonymous06:17

    Plus the camera panned in on the laptop which was showing the ctrl-alt-del to log in page

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  2. Good observations Brad. I agree it's not real -- and good call Anonymous on the laptop screen. Here are more clues I noticed:
    - instant-on cap, no electrode gel? Not with those electrodes -- those don't look like "dry" electrodes (which tend to be huge), and it's certainly not an EGI-type net with sponge electrodes. (But they could have done some creative editing and reshot a faux-capping and decapping without gel to stymie the proliferation of unglamorous screencaps of Stephen looking like a gay pornstar with his hair covered in electrode gel!)
    - where's the amp? methinks even the equipment is a sham, and the duct tape is actually forcing the mating of the EEG connector to an RS232 to a USB cable against nature's will. :-) But if this thing really exists -- i.e., a 64-electrode cap that plugs directly into a USB port -- I want one!

    The reference electrode checks out though. If you look closely at the channel labels on the running EEG, each channel is referenced to "A1A2", so linked mastoids.

    Does anyone recognize the acquisition software?

    ReplyDelete
    Replies
    1. Exactly. No amp, no gel, no EEG hair... what the heck?! And nice spot about the electrical tape. Don't know what the software is.

      Delete
  3. Anonymous22:39

    This bugged me so much I had to search and search to see if anyone picked up on this. My only electrical brain recordings are on mice but even I could tell that this was not a live recording, for all of the reasons mentioned. And the laptop was off....good catch.

    ReplyDelete
  4. Good points. They might have been referencing to something other than EOG (average, Cz, ears) so the hanging EOG is not decisive in itself. But the fact that the recording didn't turn into one huge black blob with head movement is pretty telling.

    Live EEG wouldn't make good TV. You never know in advance whether it's going to look all pretty and wave-y, or a horrible black mess of muscle spikes.

    ReplyDelete
    Replies
    1. That was kind of my point though, NS. The technology and theory is such that we should be able to a live EEG demo quickly, using dry, wireless EEG and real-time artifact cleaning. But the NIH budgets around that are nearly non-existant. Just a little ironic.

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  5. The signal also loops - check out approx 3:52 and 4:20 in the above clip :)

    ReplyDelete
    Replies
    1. You're much more observant than I! I was looking for something like that but couldn't find it. Nice.

      Delete
  6. James16:32

    Francis Collins thinks the amygdala is the brain's pleasure center?

    ReplyDelete