Events Segmentation in EEGLAB

Hello ! I am having an EEG data from more than 100 participants and it consist of 120 events. How can I segment the events into half as I am using eeglab script to process the data ? I want to analyze the first half and second half separately. Thanking you in anticipation.

Answer 1

[Prasanna]

Hi,

To segment and analyse the first and second halves of EEG events separately for each participant using EEGLAB, you can identify the events you want to segment around, create epochs for these events, and then divide the dataset based on these epochs. Given that you have 120 events per participant, and you wish to split these into two halves, here's a sample code for the same:

participants = dir('/path/to/your/data/*.set'); % Adjust the path and extension if necessary 
 
for i = 1:length(participants) 
    filename = participants(i).name; 
    EEG = pop_loadset('filename', filename, 'filepath', '/path/to/your/data/'); 
     
    % Segment into first half 
    EEG_firstHalf = pop_selectevent( EEG, 'event', [1:60], 'deleteevents', 'off', 'deleteepochs', 'on', 'invertepochs', 'off'); 
     
    % Segment into second half 
    EEG_secondHalf = pop_selectevent( EEG, 'event', [61:120], 'deleteevents', 'off', 'deleteepochs', 'on', 'invertepochs', 'off'); 
     
    % Analysis code for each half goes here 
end

For more details on the “pop_selectevent” function you can look at the documentation provided here: https://sccn.ucsd.edu/~arno/eeglab/auto/pop_selectevent.html

Hope this helps.