How to analyze the data obtained from OpenBCI_GUI unsing Ganglion board

lettiemdmlettiemdm United States
in OpenBCI_GUI
Hi everybody!

I'm a community college student and I am working in a neuroscience project. We got a headset and a ganglion board and collected data using openBCI GUI software. 
Now that we have the raw data, we are unsure as how to analyze the data (for example, we want to see if the data shows significant increase in alpha waves).
Can anybody help us?

Comments

  • wjcroftwjcroft Mount Shasta, CA
    Lettie, hi.

    Have you experimented with the Band Power widget? It shows the EEG signal amplitude (or rather, power), in each brainwave band. The band powers can also be output to a stream with the Networking widget.

    Regards,

    William

  • zfmengzfmeng Japan
    Hi!

    How could the band power be output ?

    Thank you very much.
  • wjcroftwjcroft Mount Shasta, CA
    The pulldown menu in the Networking widget allows several stream formats to be selected. And the other pulldown selects what data is to be sent over the stream. One of the data types is the Band Power data. I have not tried this personally myself, and am unclear how the 5 band values are placed into the various stream formats. This feature might have only been debugged with the serial stream format. Which likely separates the powers as CSV values.
  • zfmengzfmeng Japan
    Thank you very much.

    Could you show us a normal data file (channels, band power included) saved from OpenBCI GUI ?

    Thank you.
  • wjcroftwjcroft Mount Shasta, CA
    No, the GUI currently does not have that option.

    You could just go into the source and modify it to print the values onto a file.


    The reason I suggested the Networking widget, is that ability already exists. The idea would be to write a simple Python LSL program that receives the LSL stream from the GUI and writes to a file.


    ----

    Then again we don't exactly know the details of how the Networking widget streams the LSL band powers, you can check source,


    See lines 1457 onward, looks like the LSL case is covered at 1498. My impression is that (for Ganglion), the code is streaming 4 channels, but instead of placing the raw channel sample values in the stream -- for each 'chunk' it sends the 5 band powers. So this is assuming you sync up at the start so you know which band you are reading from the stream. Starting with delta of course, then theta, alpha, beta, gamma. Then repeat for next chunk.

    I'm not sure if chunks are at the Ganglion sample rate (200hz), or slower, check code.


  • zfmengzfmeng Japan
    Thank you very much.

    I'd like to try as you suggested.
    By the way, could the OpenBCI GUI or other available software process (like filtering) the raw data?

    Thank you. 
  • wjcroftwjcroft Mount Shasta, CA
    If you want to do more general DSP digital signal processing, the VPL, visual programming languages such as OpenViBE, BrainBay, LabView, NeuroPype, can make the DSP much easier. VPL connect DSP processing elements visually as a graph to represent signal flows.

  • lettiemdmlettiemdm United States
    Thank you so much for your help! I will try that!
  • zfmengzfmeng Japan
    Thank you very much.

    I'd like to try that. I want to get filtered signals, eliminating artifacts and get spectrograms.

    Thank you.
Sign In or Register to comment.

© Vanilla Keystone Theme 2026