Marking eeg signal


#1

Hello everyone,

I’m an experimental psychologist using Muse and its SDK to examine correlations between specific subjective meditative states with eeg data. To conduct that kind of research I need to find a way to have my participants send a marker on the recording signal when these subjective experiences do occur. In order to do that I can not use the Markers function in the SDK. Rather I’d like to use a usb response box such as the one provided by Inquisit http://www.blackboxtoolkit.com. Does someone know if there is anyways to interface the SDK with such a device.
Thank you for your time and insight.

Stephane


#2

Hi swith,

To record markers in the same file as Muse data you just need to send OSC messages representing those markers to the recording process. So to use an external button or similar device, you would need to write a simple program to turn the button press event into an OSC message, and then send that OSC message to either MuseLab or MusePlayer listening for incoming OSC messages on a particular port.


#3

Hi Swith and Tom,

I would be also interested to use some markers while recording the signals.
Swith were you able to do it? Could anyone share a sample of the simple program to write in order to turn the button press event into an OSC message…?

Thank you in advance!


#4

I am also interested in looking at correlations between subjective meditative states and EEG data. I’ve found that jaw clenches and eye blinks work great for marking event times. For example, I usually take a few minutes to settle into my meditation, then when ready to begin, I do a simple jaw clench to indicate I’m starting. At the end, I use another jaw clench to indicate the finish. If I am counting my breath and at some point lose track of the count, I indicate this with a series of 3 eye blinks; when I begin the count again, I use 2 eye blinks. A short sequence of eye blinks can be used by the subject to indicate any event of interest and I find that it doesn’t interfere with the meditation period as much as a button press might. Both jaw clenches and eye blinks are already part of the Muse data stream, so nothing else needs to be added. See www.still-breathing.net.


#5

NJM, did you ever get a response, or get anything working that could send a simple OSC message to act a a marker that you could share or e mail to me at ja356 at kent dot ac dot uk ?

Many thanks
John


#6

If you’re using Muse Monitor to stream or record data, there is “Markers Buttons” option in settings which will give you five numbered buttons at the bottom of the screen. Tapping them will inject “/Marker/1” etc into the stream.

Alternatively, you can use the USB Aux port on the Muse as a time stamp. Micro USB Pin 4 on the MU-02 model 2016 Muse is the Aux channel. You can send a pulse down this which will get logged in time sync with the other data for later parsing.


#7

Thanks Enigma644. I’d seen the Marker buttons but I needed a software solution, which I now have :slight_smile:

I’ve got pyliblo working on my mac to send OSC Marker messages through to MuseLab. (I’ve also got this working with PsychoPy so that I can inject stimulus onset event markers into the data stream.)

Next challenge it to compile liblo on my Windows 8.1 / 64bit system to get it working on that.


#8

update on this - switched to use pyOSC on Windows and now successfully injecting marker events into the data stream from python / PsychoPy