[FieldTrip] Resting State Data Source Reconstruction - covriance matrix in beamformer, and "avg" field in eLORETA

[Roey Schurr]

Dear Fieldtrippers,


First of all, a big thank you to all members of the community – it is a
wonderful place to learn in and share ideas, thoughts and solutions to
common problems we all face.


I am writing you since I fear I might be missing something trivial: I am
trying to compute an inverse solution to to resting-state EEG data. Two
question arise, depending on the method I am trying to use:


1)      Using a beamformer technique such as LCMV, a covariance matrix is
needed. However, since the data is not time-locked (like ERP), the
covariance matrix cannot be easily computed over the averaged trials. Can
it be estimated using different resting-state trials?

2)      Using eLORETA as the source reconstruction method (since my goal is
a time-domain source reconstruction), it seems the the "avg" field is neeed
in the data. Once again, no such average is available, since these are not
ERP trials.

Would you advise me to revise the code and try to fit it to non-ERP data,
or is there some easier way I'm missing?


Thank you all,

Best,

roey
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