[FieldTrip] ERP image from EEGlab in fieldtrip and power normalisation without baseline

[Vitoria Piai]

Hi everyone,

In EEGlab, there is an interface to make the so-called ERP image: 
single-trial data is sorted, for example on the basis of RT, and plotted 
with a vertical line showing stimulus onset and another line showing the 
RTs. An example is shown here:
http://sccn.ucsd.edu/wiki/File:1ERPimageinf.gif
Has anyone ever implemented this in fieldtrip in a straightforward way? 
Or managed to interface with EEGlab and make these plots with FT 
structured data?
I scripted some code outside of FT to make this kind of figure but they 
didn't look as nice - neither the code nor the figure :)
I've never tried exporting from FT to EEGlab, maybe that's the only way 
to go about... but if anyone has thought about this as well, I'd be 
happy to hear.

The other thing I was wondering about is whether it'd work to make the 
same kind of figure but instead of using single-trial phase-locked 
activity, I'd use single-trial alpha power over time (averaged over a 
frequency range) instead.
The problem I have in this case is that I don't have a valid baseline 
period to normalise against. I was reading some earlier threads about 
power normalisation (e.g., 
http://mailman.science.ru.nl/pipermail/fieldtrip/2012-March/004862.html) 
but many of the suggestions made still rely on pre- vs. post-stimulus 
normalisation. The usual (cond1 - cond2) / (cond1 + cond2) and its 
variations won't work here either since it's single-trial data. Should I 
give up or is there something I actually could do?

I'm looking forward to hearing any thoughts you may want to share!
Cheers, Vitória