[Eeglablist] Extracting Phase Angle from ITC Matrix

[Arnaud Delorme]

Dear Zach and Indir,

I would recommend to use the function timefreq instead of phasecoher  
to compute single-trial wavelet decompositions (and ITC).
Phasecoher is an old function that will be retired soon (and replaced  
by timefreq).

Best,

Arno

On Nov 27, 2009, at 6:18 PM, Zachary Moran wrote:

> Thank you, everyone!  These are incredibly helpful tips.
>
> On Fri, Nov 27, 2009 at 11:44 AM, Indir Jaganjac  
> <ijaganjac at yahoo.com> wrote:
> Hi Zach,
>
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> 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]
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> regards,
> I. Jaganjac
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> From: Zachary Moran <zdmoran at gmail.com>
> Precedence: list
> MIME-Version: 1.0
>
> To: eeglablist at sccn.ucsd.edu
> Date: Tue, 24 Nov 2009 15:28:00 -0800
> Message-ID: <93a92c840911241528v33775b77q8319fffc9354f77b at mail.gmail.com 
> >
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> Subject: [Eeglablist] Extracting Phase Angle from ITC Matrix
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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
>
>
>
>
> <ATT00001.txt>

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