Hello Jan-Mathijs,<br><br>I'm able to find the complex trial data now, but I've been avoiding the mtmconvol method because I don't have very good grasp on it. I'm getting phase angles greater than pi. Is there a simple way to run it on some simulated data? <br>
<br>I'm trying to find a periodic signal at 2Hz with non-stationary gamma transients linked to its phase.<br><br>Thanks for any feedback!<br><br>-karl<br><br><div class="gmail_quote">On Wed, Mar 10, 2010 at 3:32 PM, jan-mathijs schoffelen <span dir="ltr"><<a href="mailto:jan.schoffelen@donders.ru.nl">jan.schoffelen@donders.ru.nl</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">Hi Karl,<br>
<br>
freqanalysis with method = 'mtmconvol' allows you to keep the fourier coefficients (cfg.output = 'fourier') so you'll get a complex representation there.<br>
<br>
Best,<br>
<br>
Jan-Mathijs<div><div></div><div class="h5"><br>
<br>
<br>
On Mar 10, 2010, at 2:36 PM, Karl Doron wrote:<br>
<br>
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
Hello,<br>
<br>
I'm looking at some MEG data and have a hypothesis about cross frequency<br>
coupling. Specifically, a relationship between lower frequency phase and<br>
higher frequency amplitudes. I'm trying to save and view the phase angles<br>
after doing wavelet analysis using wltconvol.<br>
<br>
If this is implemented -great! Otherwise, it seems that somewhere after line<br>
216 of ft_freqanalysis_wltconvol.m (after the ifft), I should be able to<br>
save the complex numbers and use angle(input) to find the phase angle of<br>
each time point on a trial by trial basis. It seems easier to do in the<br>
'tfr' wavelet code, but the time domain covolution is very slow.<br>
<br>
Thanks for any help!<br>
<br>
Karl Doron<br>
<br>
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The aim of this list is to facilitate the discussion between users of the FieldTrip toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also <a href="http://listserv.surfnet.nl/archives/fieldtrip.html" target="_blank">http://listserv.surfnet.nl/archives/fieldtrip.html</a> and <a href="http://www.ru.nl/neuroimaging/fieldtrip" target="_blank">http://www.ru.nl/neuroimaging/fieldtrip</a>.<br>
<br>
</blockquote>
<br></div></div>
Dr. J.M. (Jan-Mathijs) Schoffelen<br>
Donders Institute for Brain, Cognition and Behaviour,<br>
Centre for Cognitive Neuroimaging,<br>
Radboud University Nijmegen, The Netherlands<br>
<a href="mailto:J.Schoffelen@donders.ru.nl" target="_blank">J.Schoffelen@donders.ru.nl</a><br>
Telephone: 0031-24-3668063<div><div></div><div class="h5"><br>
<br>
----------------------------------<br>
The aim of this list is to facilitate the discussion between users of the FieldTrip toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also <a href="http://listserv.surfnet.nl/archives/fieldtrip.html" target="_blank">http://listserv.surfnet.nl/archives/fieldtrip.html</a> and <a href="http://www.ru.nl/neuroimaging/fieldtrip" target="_blank">http://www.ru.nl/neuroimaging/fieldtrip</a>.<br>
</div></div></blockquote></div><br>
<p>----------------------------------</p>
<p>The aim of this list is to facilitate the discussion between users of the FieldTrip toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis.</p>
<p> http://listserv.surfnet.nl/archives/fieldtrip.html</p>
<p> http://www.ru.nl/fcdonders/fieldtrip/</p>