Hello MNE forum! I am running into problems when trying to use LCMV beamformers on evoked MEG data (mags & grads) with a volume source space. using an empty-room noise covariance matrix and a data covariance matrix computed from the epochs leads to confetti-like source activation values (upper r…

[image] richard: Not sure what the “correct” approach would be! I would use the rank of the matrix that is doing the whitening. So @sophie in your case compute rank from the empty-room raw, not from the epoched / evoked task data, or process the empty-room in an identical way and you will pro…

MRG, ENH: Add warning about bad whitener conditioning mne-tools:main ← larsoner:cond opened 05:41PM - 28 Jan 21 UTC (UTC) [larsoner] larsoner …

Strange source activity with lcmv beamformer in volume source space (empty room covariance)

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larsoner (Eric Larson) January 28, 2021, 5:41pm 21

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Strange source activity with lcmv beamformer in volume source space (empty room covariance)

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