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Dear community,</div>
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Although I’ve seen other questions related to this topic, I still have some questions regarding baseline correction when executing a time-frequency analysis:</div>
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After time-frequency analysis, I want to use the trial output either to compare (within participants) trials from different conditions or to put the datapoints of different trials into a regression (also on participant level). </div>
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The question for me is how to deal with a baseline correction in this situation? The data before each trial of interest is in reaction to viewing a fixation cross.</div>
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<font face="Calibri,sans-serif">If I understand it correctly, with the default config setting for</font> <span style="font-size: medium;">cfg.polyremoval the mean of the whole trial is subtracted (prior to spectral analysis) </span><span style="font-family: Calibri, sans-serif;">to
get rid of the offset in oscillations.</span></li><li><font face="Calibri,sans-serif">Does it mean that since I’m doing analyses on a participant level first, I only need to do this kind of baseline correction (from stimulus onset on)?</font></li><li><span style="font-family: Calibri, sans-serif; font-size: 14px;">I thought that I should
</span><i style="font-family: Calibri, sans-serif; font-size: 14px;">not</i><span style="font-family: Calibri, sans-serif; font-size: 14px;"> subtract the mean of a window prior to stimulus onset, from the raw trial data before doing time-frequency analysis
(the kind of baseline correction you would do with ERP analyses), but I see this happening in some articles. Did I not get it right, or is this related to the distinction between evoked and induced power, or something else?</span></li><li><font face="Calibri,sans-serif">Or is it an option (and should I) subtract the mean of a window prior to stimulus </font><font face="Calibri,sans-serif">onset only after decomposition of the data in the </font><font face="Calibri,sans-serif">power spectrum,
for all trials?</font></li></ol>
<div>Thanks a lot!</div>
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<div><font face="Calibri,sans-serif">Best,</font></div>
<div><font face="Calibri,sans-serif">Esther</font></div>
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