[Eeglablist] Mismatch in duration between EEG struct and eegplot()

[Oda van Jole]

Hi,


I have encountered a strange problem, namely a mismatch in duration between EEG struct and the x-axis in eegplot(). I am pre-processing a resting state EEG recording that consists of 5 minutes eyes open (EO) and 5 minutes eyes closed (EC), in addition to some seconds before, between, and after these sections.  I extract the two 5 min sections using pop_select() into an EEG struct (EEGconds) containing the resulting two EEG structs from pop_select() - EO and EC. For each of them, EEG.xmax, size(EEG.data, 2), and the "Epoch end (sec)" in GUI indicates a duration of 300s as expected. When calling eegplot() from code, the x-axis will go to 600 seconds, even with an eeglab redraw first. However, if I use eegplot() manually via GUI, it stops at the 300 sec as expected. Why does this happen? Am I doing something wrong?


Code:


% Extract sections

EOstart = EEG.event(find([EEG.event.edftype] == 1)).latency;

EOend = EEG.event(find([EEG.event.edftype] == 2)).latency;

EEGEO = pop_select(EEG, 'point', [EOstart, EOend]);

% Repeat for EC but with correct event edftypes.


EEGconds.EO = EEGEO; EEGconds.EC = EEGEC;


EEG = EEGconds.EO;

EEG.xmax                                       % ~300

size(EEG.data, 2)/EEG.srate        % ~300

eegplot(EEG.data)                        % Now I can scroll to 600 sec

eeglab redraw;

eegplot(EEG.data)                       % can still scroll to 600s


This also occurs even if I delete EEGconds from the workspace after assigning EEGconds.EO to EEG.


Thanks very much in advance for your help!


Best wishes,

Oda van Jole