[Eeglablist] Extracting Phase Angle from ITC Matrix

[Indir Jaganjac]

Hi Zach,
 
 
 
 
 
 
Mr.Bradley Voytek and Dr.Aranud Delorme have made excellent comments.
 
 
My experience is:
 
Inter-Trial Coherence (ITC) or phase-locking factor is important for detection of
transient event-related spectral perturbation (ERSP). 
ERSP/ITC frequency range is usually in 3-25 Hz.
 
You can extract phase angle P and magnitude M, from Inter-Trial Coherence (ITC) matrix in this way:
P = angle(ITC), where P is phase angle matrix in radians, for each element in ITC matrix (in interval -pi,+ pi).
M = abs(ITC), where M is magnitude.
 
You can also try function phasecoher for estimating inter-trial amp/coherence using Gaussian wavelets:
[amps,cohers ] = phasecoher(data,frames,srate,freq,cycles);
amps = mean amplitude at each time point
cohers = phase coherence at each time point [0,1]
 
 
 
  
 
 
 
 
regards,
I. Jaganjac
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
From: Zachary Moran <zdmoran at gmail.com>
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Hey everyone,
I'm wondering whether anyone knows how to extract an estimate of phase angle
(or average phase angle) from the newtimef ITC output matrix.  When I look
at the matrix, I can see that the estimates in each cell are provided in
complex number form - does part of this number pertain to phase angle for
that frequency and time point?  Any help or information would be greatly
appreciated!
Many thanks,
Zach

 


      
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