marking 'events' [artifacts]
nejemia
argentina
Hello !
I need to mark events during the Recording of the EEG, like Blink Eyes, Head moving, etc.
How do I do that with the OpenBCI_GUI?
Thanks a lot.
Nelson
Comments
Nelson, these are not generally called 'events'. That term is usually applied to external triggers such as stimulus presentation, button presses, etc. The actual term is artifact. Some algorithms in the next post.
https://www.google.com/search?as_q=artifact+algorithm&as_sitesearch=openbci.com
In particular see this thread with the algorithm link for SARA,
https://openbci.com/forum/index.php?p=/discussion/1258/artifact-detection-thresholds-algorithms
Hello William.
Excellent reference.
I am looking for a way that I can stamp manually on the Recorded study a mark that once I do post analysis of the EEG I can reference the particular event, not an artifact, lets say, patient closed eyes, patient moved head, this is information that I want to analyze after recording, not only to suppress the artifact. I want also to have this information superimposed on the recording. Like Minute 3:32 patient Closed Eyes.
If I can insert in some place of the stream a single character (for instance) this will do !
Sorry, it is hard for me to express the idea in English... But I believe you understand.
Cheers.
Nelson.
Manual operator annotation of EEG records can be done with EDFBrowser and other EEG editing utilities. OpenBCI_GUI does not do this.
The use of External Triggers on one of the three Cyton Aux channels, could provide a marker in the EEG stream, but not annotation.
https://docs.openbci.com/docs/02Cyton/CytonExternal
You got it! This is exactly what I was looking for. So, the mark of an external event must be done on the Cyton, I will work it out.
Thanks a lot.
Nelson
These artifacts occur so frequently, that manual button press 'event' marking of such artifacts, will be extremely tedious and error prone. Not to mention the human reaction time delay factors.
Also, any EEG technician can recognize eye blink, head motion artifacts in a recording, just by the nature of what is visible on the different channels. Eye blinks are more prominent in frontal areas. Head motion tends to skew all channels momentarily. Etc.
Dear William.
The manual "marking" option is our neurologist requirement. The idea is to provide the recorded studies with additional information for the post processing task. Of course it is not mandatory, but since they are used to have this feature with other display software, I believe that providing the OpenBCI_GUI with it, will be an asset.
I will dig more on the issue and keep you posted.
All the best!
Nelson