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--></style></head><body lang=EN-GB link=blue vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal>Hi,</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I have 10 patients and 10 controls and I am interested in analysing their connectivity (e.g., wPLI). Each subject’s EEG was recorded with 28 electrodes.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Each subject has ~ 50 trials of resting state with open eyes.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The ultimate goal is to investigate whether there are differences in connectivity between patients and controls inside a band (e.g., alpha) in any given pair of electrodes.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>So far, I have based my processing pipeline for each subject on <a href="https://www.fieldtriptoolbox.org/tutorial/networkanalysis_eeg/">the EEG network analysis tutorial</a>, BUT I stayed at the electrode-level and I have not done anything related to source estimation. Thus, the pipeline is roughly:</p><p class=MsoNormal><o:p> </o:p></p><ol style='margin-top:0cm' start=1 type=a><li class=MsoListParagraph style='margin-left:0cm;mso-list:l0 level1 lfo1'>Re-referencing (<i>ft_preprocessing</i>)</li><li class=MsoListParagraph style='margin-left:0cm;mso-list:l0 level1 lfo1'>Frequency filtering (<i>ft_preprocessing</i>)</li><li class=MsoListParagraph style='margin-left:0cm;mso-list:l0 level1 lfo1'>Definition of trials (<i>ft_redefinetrial</i>)</li><li class=MsoListParagraph style='margin-left:0cm;mso-list:l0 level1 lfo1'>Computing Fourier complex spectrum (<i>ft_freqanalysis </i>with <i>cfg.output=’fourier’</i>)</li><li class=MsoListParagraph style='margin-left:0cm;mso-list:l0 level1 lfo1'>Computing connectivity (<i>ft_connectivityanalysis</i>)</li></ol><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Now, I would like to aggregate the subject-level data and perform some visual/statistical analysis on group-level data. Unfortunately, I have not found anything in the Wiki nor the repo on how to compute the grand average of connectivity data (I tried <i>ft_freqgrandaverage </i>but it crashes).</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I searched inside this mailing list’s archives, and found <a href="https://mailman.science.ru.nl/pipermail/fieldtrip/2013-December/007355.html">this</a> thread where Bart confirms he has “... averaged the connectivity measures between subjects for the grand average comparison”, but does not state how.</p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Despite the caveats mentioned by Jan-Mathijs in that thread, how can I compute the grand average between the subject-level connectivity measures?</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Also, how can I conduct a statistical test for this experiment (similarly to ft_freqstatistics)?</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks in advance!</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Best regards,</p><p class=MsoNormal>Luis Bolanos</p></div></div></body></html>