<!doctype html public "-//W3C//DTD W3 HTML//EN">
<html><head><style type="text/css"><!--
blockquote, dl, ul, ol, li { padding-top: 0 ; padding-bottom: 0 }
--></style><title>Re: [Eeglablist] channel
cross-coherence</title></head><body>
<div>Dear Arno,</div>
<div><br></div>
<div>I understood that the Lachaux method was used to calculate pure
phase synchrony across channels. It sounds like the cross
channel phase coherence function does essentially the same thing,
although it is unclear how the calculations differ. </div>
<div><br></div>
<div>I will try to run this past Eugenio Rodriques. </div>
<div><br></div>
<div>Thanks.</div>
<div><br></div>
<div>Dan</div>
<div><br></div>
<blockquote type="cite" cite>Daniel Mathalon wrote:<br>
<blockquote type="cite" cite>Re: [Eeglablist] channel
cross-coherence</blockquote>
<blockquote type="cite" cite>Dear EEGLAB gurus,</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>There were a couple of recent posts (see
below) regarding cross-channel coherence analyses. It is unclear
what the distinction is between phase coherence and linear coherence,
and it seems that neither of them calculates pure phase synchrony (as
is done with the Lachaux et al method).<br>
</blockquote>
</blockquote>
<blockquote type="cite" cite>Phase coherence calculates PURE phase
synchrony (which is independent of signal amplitude). Linear coherence
takes indeed phase as well as amplitude information. Amplitude
correlation would take into account only amplitude information. For
the exact formula of phase coherence and linear coherence, see <a
href="http://repositories.cdlib.org/postprints/357/"
>http://repositories.cdlib.org/postprints/357/</a><br>
<br>
I do not know exactly which one of Jean Philippe Lachaux method you
are refering to. His main method I think relates to studying phase
coherence (or ITC/phase locking factor) in single trial using binary
ERP-image like display. Eugenio Rodrigues is working a plugin with
these functions for EEGLAB (do not hesitate to email him to motivate
him).<br>
<br>
Best regards,<br>
<br>
Arno<br>
<blockquote type="cite" cite>Can someone comment on how these
cross-channel coherences are calculated and whether there is a plan to
add a pure cross-channel phase synchrony measure to
EEGLAB?</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>Thanks,</blockquote>
<blockquote type="cite" cite><br>
Dan Mathalon<br>
</blockquote>
</blockquote>
<blockquote type="cite" cite><br>
_______________________________________________<br>
eeglablist mailing list eeglablist@sccn.ucsd.edu<br>
Eeglablist page: http://sccn.ucsd.edu/eeglab/eeglabmail.html<br>
To unsubscribe, send an empty email to
eeglablist-unsubscribe@sccn.ucsd.edu</blockquote>
<div><br></div>
<div><br></div>
<x-sigsep><pre>--
</pre></x-sigsep>
<div>Daniel H. Mathalon, Ph.D., M.D.<br>
Assistant Professor of Psychiatry<br>
Yale University School of Medicine<br>
<br>
Mail Address:<x-tab> </x-tab>Psychiatry Service 116a<br>
<x-tab> </x-tab><x-tab>
</x-tab>VA Connecticut Healthcare System<br>
<x-tab>
</x-tab><x-tab> </x-tab>950
Campbell Ave<br>
<x-tab>
</x-tab><x-tab> </x-tab>West
Haven, CT 06516<br>
<br>
Fax:<x-tab>
</x-tab><x-tab>
</x-tab>(203) 937-3886<br>
Office Phone:<x-tab> </x-tab>(203) 932-5711,
ext. 5539<br>
Pager:<x-tab>
</x-tab><x-tab>
</x-tab>(203) 867-7756</div>
</body>
</html>