<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//DE"><HTML><HEAD><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii"><TITLE>Message</TITLE></HEAD><BODY>Hi Bjoern,<br>
<br>
I am not sure what you mean by 'back/front'. If you
want a simple 2D topoplot, this is how I do it. I assume that you have
already loaded your two conditions in the eeglab GUI. Alternatively,
replace 'ALLEEG' with the names of the variables holding your two EEG
sets. The code is a bit verbose for the sake of clarity. Of course, the
code could be more compact. <br>
<br>
Cheers,<br>
Niko<br>
<br>
PS: I sent this message to your email addresses before, but the emails bounced back.<br>
<br>
%-------------------------------------<br>
% Average over a time window, specified in SECONDs. Convert the time to<br>
% sampling points.<br>
win_start = 0.100;<br>
win_end = 0.300;<br>
tlim = round(eeg_lat2point( [win_start win_end], 1, ALLEEG(1).srate, [ALLEEG(1).xmin ALLEEG(1).xmax])); <br>
<br>
% Average data over trials, then subtract the two conditions to get the<br>
% effect. Finally, average the effect over your time window of interest.<br>
data1 = mean(ALLEEG(1).data,3);<br>
data2 = mean(ALLEEG(2).data,3);<br>
effect = data2 - data1;<br>
<br>
winmean = mean(effect(:,tlim(1):tlim(2)),2);<br>
<br>
% Plot the figure. Modify the topoplot options as you see fit.<br>
figure;<br>
topoplot(winmean, ALLEEG(1).chanlocs); <br>
%-------------------------------------</BODY></HTML>