[Eeglablist] Problem with base line in time-frequency

[Johan.poncelet]

Dear all,

I use EEGlab for a few month now for Evoked potential in olfaction. I 
tried to make some time frequency but the result have not convinced me. 
In fact, i have a problem in baseline.

I have epoched my data from -1000 ms to +2000ms in order to have a very 
large one.
When I apply the time frequency function (study, compute ERSP), I obtain 
a time freq representation from -126ms to 1200ms maxi.

Why?

I have done the ERSP with this parameters:
 'cycles', [3 0.5], 'padratio', 4, 'freqs', [2 100], 'lowmem', ['on'] , 
'freqscale', ['linear'],

Now i would like to do different ERSP. I would like that the [-1000, 
-500] period to be my baseline. And then have a representation from -500 
to +1500.  Is it possible? I have tried with the option 'baseline' in 
the ERSP box but EEGlab give me error message.

Regards
Johan.Poncelet

-- 
Johan Poncelet
Laboratoire Neuroscience et Systèmes Sensoriels
CNRS UMR 5020
Equipe Variabilité et Plasticité de l'Audition
Université Claude Bernard Lyon 1
50, avenue Tony Garnier
69366 LYON cedex 07
Tel 06 81 88 66 92
Johan.poncelet at olfac.univ-lyon1.fr
Johan.poncelet at gmail.com