[Eeglablist] EEG Coherence

[T. Almabruk]

Hi List

I asked a question before about measuring EEG coherence by EEGLAB. I got benifits from the answer i got  but still have something wrong. I applied the function to the same dataset provided with EEGLAB tutorial. i filtered the data first and then extract the epoches (153). After that i run ICA and ploted component cross-coherence between channel 4 and channel 9.
As you can see fig(1) was the result and i tried to zoom it in (fig 2).
I wanted to compare the result with that can be done by matlab function (Mcoher) and fig(3) represents the results i got.
My question is that, there is a big difference in the coherence's amplitude between the two functions where using EEGLAB the amplitude is less that 0.1 where with Mcohere as you can see is close to 1.

I'm sure i miss undeerstand something because i'm new with this area and hope i can find some help from you .

Cheers,
Tahani

http://www.flickr.com/photos/94417587@N05/
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