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<p>Dear all</p>
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<p>I am using FieldTrip to explore connectivity in resting-state EEG data and aimed to use the debiased weighted phase lag index (dwPLI) to index this. However, I am finding a lot of negative values in my connectivity matrices when I compute the dwPLI, and
I am unsure why this might be - has anyone found this previously, or have an idea of why this might be happening? I do not get this if I compute other connectivity measures (e.g. coherence) and I have a decent amount of clean trials (around 80 per subject)
on which to run the connectivity. I am computing the dwPLI from fourier coefficients exported from a straightforward FFT. </p>
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<p>Many thanks in advance for any advice</p>
<p>Best wishes</p>
<p>Lizzie</p>
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<p class="MsoNormal" style="margin-bottom:0.0001pt"><span style="font-family:"Garamond","serif"; color:#1F497D">---------------------------------------------------------------------------</span><span style="font-family:"Garamond","serif"; color:black"></span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt"><span style="font-family:"Garamond","serif"; color:#1F497D">Lizzie Shephard, PhD</span><span style="font-family:"Garamond","serif"; color:black"></span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt"><span style="font-family:"Garamond","serif"; color:#1F497D">Postdoctoral researcher</span><span style="font-family:"Garamond","serif"; color:black"></span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt"><span style="font-family:"Garamond","serif"; color:#1F497D">2.21 MRC SGDP Centre</span><span style="font-family:"Garamond","serif"; color:black"></span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt"><span style="font-family:"Garamond","serif"; color:#1F497D">Institute of Psychiatry, Psychology, & Neuroscience</span><span style="font-family:"Garamond","serif"; color:black"></span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt"><span style="font-family:"Garamond","serif"; color:#1F497D">King’s College London</span><span style="font-family:"Garamond","serif"; color:black"></span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt"><span style="font-family:"Garamond","serif"; color:#1F497D">De Crespigny Park</span><span style="font-family:"Garamond","serif"; color:black"></span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt"><span style="font-family:"Garamond","serif"; color:#1F497D">London, SE5 8AF</span><span style="font-family:"Garamond","serif"; color:black"></span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt"><span style="font-family:"Garamond","serif"; color:#1F497D">0207 848 5272</span><span style="font-family:"Garamond","serif"; color:black"></span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt"><span style="font-family:"Garamond","serif"; color:#1F497D">elizabeth.1.shephard@kcl.ac.uk</span></p>
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