Hello Brainstorm Community,
I would like to import my resting state MEG recordings (3 minutes = 180s) after cleaning my data using the linked file system presented in the tutorials. However, upon importing, BS asks to select my epochs (again, resting state, so no events). In the past, I've used 120 seconds and divvied them into 2 second epochs (for a total of 60 raw files). I cannot compute the source localisation on the raw files because they're not continuous, and as such I have to average them. The result is a 2 second file which is the average of all 60 epochs per subject.
However, I have 2 problems with this method:
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After projecting to the default anatomy, and trying to compute the PSD, I get a warning that the 2 seconds aren't enough. In other words, the 2 second data form is limiting analyses.
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Averaging, to me, means I lose a lot of data. Condensing entire recordings to 2 seconds seems anti-climatic.
So, my question is as follows:
Is there a way to compute sources on my entire recordings without splitting the data into epochs when I import them to the database? My idea is to create one epoch that defines the length of my recordings (epoch length: 0-180s, one epoch). If that is not advisable, what would be a recommended epoch length?
The resting OMEGA tutorial uses the CTF system which lets them convert their raw recordings (without the need to average) between epochs and continuous data, a luxury I don't have. I get the error message "Conversion from epoched to continuous is only available for CTF .ds files" when I try to do that.
My warmest gratitude for your time and response.
Best,
Aquila.