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<p class="MsoNormal"><span lang="EN-US">Dear Fieldtripper,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I’m working on a spectral analysis of LFP data and calculated so far time-frequency spectra for every single trial. To describe the consistency/variability of phases on every time-frequency bin over trials I calculated
‘Inter-trial Phase coherence (ITPC)’ as described in the fieldtrip tutorial. <o:p>
</o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">But, what would I do to determine the consistency/variability of the power (squared amplitude) for every time-frequency bin over trials? Maybe simply calculate for every time-frequency bin a Standard Deviation over trials
and relate this to the according mean:<o:p></o:p></span></p>
<p class="MsoListParagraphCxSpFirst" style="margin-left:20.4pt;mso-add-space:auto">
<span lang="EN-US">Variability(t,f) = Standard Deviation(t,f) / mean(t,f)<o:p></o:p></span></p>
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<span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Would it be that simple, or am I running into some statistical trouble (maybe because the power values are not normally distributed or anything else). Should I baseline correct the single trials before calculating the
‘variability’ of the power amplitude. Or am I missing an important point and the whole idea is not meaningful at all?
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Would be great if anyone has an idea, an answer, or even just a hint for a reference to read (couldn’t find one so far)…<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Thanks!<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Iris <o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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