Importing MEG Resting State data with BAD segments/events

Bugs
1

Hi Brainstorm developers,

I marked my raw recordings with some bad segments. However, when I import to the database, the program doesn't recognize that only a section of the data is marked as bad, and it doesn't detect any recordings in the process one tab. I think this is because events are oriented towards epoched data, and any epochs with bad segments would be ignored from the analysis, and in my case, the program interpreted my entire 3 minutes of imported data as an epoch that contains a bad segment.

I have a screenshot here detailing how I imported the data from the raw file link, which had the bad event tag:

importing bad segments primo.png3360×1050 630 KB

Note here that after importing the data, Brainstorm doesn't recognize that there are any recordings in the Imported data folder, but it recognizes that the raw files folder contains a recording:

importing bad segments.png3360×1050 637 KB

I can confirm that the program correctly detects recordings for subjects without bad events/tags, because I only realised this error when I wanted to compute the sources for all 32 of my subjects and Brainstorm only detected 24 files (which didn't have the Bad event tags).

Is there a workaround for this or do I have to somehow get rid of the noisy segments?

Thanks,

Aquila.

2

In the continuous files (“Link to raw”), the bad segments are considered individually. If you compute a PSD from this link, only the bad segments will be considered as bad.

When importing your recordings (= epoching = copying to the database), the epochs that contain at least one sample marked as bad will be considered as bad. The bad epochs are then completely ignored from the analysis, and cannot be selected in the Process1 tab. This corresponds to a logic of ERP analysis, and I agree it may not correspond to all the types of analysis.

To get access to this data again, you need to mark the epoch as good (right-click on it in the database explorer), but this will not consider the bad segment anymore. Otherwise, split the recordings in smaller epochs and mark as bad only the ones that contain the artifacts.
Why do you need to import such long epochs? If your goal is to compute power measures, you can do this from the continuous recordings directly.