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Dear fieldtrip users,<br><br>I am trying to compute a spatial filter<br>to localize alpha-band activity in an<br>eyes closed resting state meg recording<br>using the LCMV-method.<br><br>The condition of my covariance matrix is > 1*10e6<br>so I set lambda = 0.01. When I then plot the NAI<br>I find two clusters of activity: <br>one in the center of the head,<br>one in the occipital cortex.<br><br>In Exercise 5 of the tutorial, it is <br>mentioned to set lambda to 1e-29 in order <br>to suppresses the center of head artifact.<br><br>I wanted to ask if anybody could tell me what the<br>rationale was to set lambda = 1e-29? <br>Is there a standardized way to compute lambda?<br><br>Best regards,<br><br>Fred<br><br>-- <br>Frédéric Roux, PhD student<br>Department of Neurophysiology<br>Max Planck Institute for Brain Research<br>D-60529 Frankfurt am Main<br>Frederic.Roux@brain.mpg.de<br>+49(0)69630183225<br><br> </div></body>
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