[Eeglablist] Rejecting data using events

[Arnaud Delorme]

Dear Puneet,

there is no way yet to remove events the way you mentioned using EEGLAB 
graphic interface. However, while preserving backward compatibility, we 
have added a duration field to each event that will be standard and 
could be processed in EEGLAB (this was possible before but the duration 
information could not be used in a systematic way). So we are heading in 
that direction.
In the meantime, you can always remove events from the command line, 
using something like

% find events 1 latencies
% --------------------------
eventtypes       = cell2mat( {EEG.event.type}); % assumes number for type
eventlatencies = cell2mat( {EEG.event.latency});
boundaries = find(eventtypes == 1);
eventlatencies = eventlatencies(boundaries);

% remove regions
% ------------------
removeregions = reshape( eventlatencies, length(eventlatencies)/2, 2);
EEG = eeg_eegrej(EEG, removeregions)

% update GUI
% -------------
[ALLEEG EEG CURRENTSET] = eeg_store(ALLEEG, EEG, CURRENTSET);
eeglab redraw;

Arno

Puneet Khattar wrote:

> We have continuous eeg data that is collected in neuroscan (cnt 
> file) and we want to remove the artifacts. It seems that EEGLab only 
> allows artifact rejection in continuous data through visual 
> inspection. We went into neuroscan and set a threshold to mark the 
> artifacts. When we imported this cnt file into EEGLab, the marked off 
> areas that we want to reject are inbetween events of type 1. Is there 
> a way to remove the continuous data inbetween two events? (start 
> removing data when event 1 occurs, stop when event 1 occurs again, and 
> repeat)
>  
> Puneet Khattar
> Cognitive Neuroscience Laboratory
> UCSD



-- 

*Arnaud Delorme, Ph.D.*
Computational Neurobiology Lab, Salk Institute
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