[Eeglablist] Merging two dataset

Tue Sep 24 00:17:15 PDT 2024

Hi dear community,

I have one problem that I could not solve myself. I have two eeg datasets, one for mother and one for infant. They are for eeg hyperscanning experiment. I recorded these two datasets with separate amplifiers and in separate files with brain recorder. As I should use a pipeline for analyzing my data, I should import infant and mother's data to MATLAB in one file and not separated. Therefore, I should merge my data. Bothe data has the same sampling rate 500 but there is two problems:

1.The name of the channels in two datasets are different
2.Data points in two datasets are different because I started recording for one of the participants with delay as I had two systems(they have the same number of markers)

I solved the channel's name. I changed the channels' name of one of the datasets to avoid any confusion. But I do not know how I can match the data point in two datasets and then I can merge them.

Below, it is a code that I am using for changing the channels' name and merging but it prefers one of the channels' names and ignores the channels' name of other dataset and then merges both datasets.

% Load EEGLAB
eeglab;

% Define file paths and file names for the first dataset
filepath1 = 'C:\Users\goharbakhsh\Desktop\EEG\ostracism hyper\original EEG data\New folder\New folder'; % Replace with your actual path
filename1 = 'infant.vhdr';       % Replace

% Load the first dataset
EEG1 = pop_loadbv(filepath1, filename1);

% Define file paths and file names for the second dataset
filepath2 = 'C:\Users\goharbakhsh\Desktop\EEG\ostracism hyper\original EEG data\New folder\New folder'; % Replace with your actual path
filename2 = 'mother.vhdr';       % Replace

% Load the second dataset
EEG2 = pop_loadbv(filepath2, filename2);

% Example: Add a prefix "m_" to all channels in EEG2
for i = 1:length(EEG2.chanlocs)
    EEG2.chanlocs(i).labels = ['m_' EEG2.chanlocs(i).labels];
end

% Display updated channel labels in EEG2
disp({EEG2.chanlocs.labels});

% Merge the two datasets
EEG_merged = pop_mergeset(EEG1, EEG2, 0);

% Saving mergeg data
pop_writebva(EEG, fullfile(outputPath, outputFilename));

The *vhdr file of the data should be in the format below for the pipelin. There are 64 channels, half of them is for the mothers and half is for infants.

[Channel Infos]
; Each entry: Ch<Channel number>=<Name>,<Reference channel name>,
; <Resolution in "Unit">,<Unit>, Future extensions..
; Fields are delimited by commas, some fields might be omitted (empty).
; Commas in channel names are coded as "\1".
Ch1=Fz,,0.1,µV
Ch2=F3,,0.1,µV
Ch3=F7,,0.1,µV
Ch4=F9,,0.1,µV
Ch5=FT7,,0.1,µV
Ch6=FC3,,0.1,µV
Ch7=FCz,,0.1,µV
Ch8=Cz,,0.1,µV
Ch9=C3,,0.1,µV
Ch10=T7,,0.1,µV
Ch11=CP3,,0.1,µV
Ch12=Pz,,0.1,µV
Ch13=P3,,0.1,µV
Ch14=P7,,0.1,µV
Ch15=PO9,,0.1,µV
Ch16=O1,,0.1,µV
Ch17=Oz,,0.1,µV
Ch18=O2,,0.1,µV
Ch19=PO10,,0.1,µV
Ch20=P8,,0.1,µV
Ch21=P4,,0.1,µV
Ch22=CP4,,0.1,µV
Ch23=TP10,,0.1,µV
Ch24=T8,,0.1,µV
Ch25=C4,,0.1,µV
Ch26=FT8,,0.1,µV
Ch27=FC4,,0.1,µV
Ch28=F4,,0.1,µV
Ch29=F8,,0.1,µV
Ch30=F10,,0.1,µV
Ch31=VEOG1,,0.1,µV
Ch32=VEOG2,,0.1,µV
Ch33=2_Fz,,0.1,µV
Ch34=2_F3,,0.1,µV
Ch35=2_F7,,0.1,µV
Ch36=2_F9,,0.1,µV
Ch37=2_FT7,,0.1,µV
Ch38=2_FC3,,0.1,µV
Ch39=2_FCz,,0.1,µV
Ch40=2_Cz,,0.1,µV
Ch41=2_C3,,0.1,µV
Ch42=2_T7,,0.1,µV
Ch43=2_CP3,,0.1,µV
Ch44=2_Pz,,0.1,µV
Ch45=2_P3,,0.1,µV
Ch46=2_P7,,0.1,µV
Ch47=2_PO9,,0.1,µV
Ch48=2_O1,,0.1,µV
Ch49=2_Oz,,0.1,µV
Ch50=2_O2,,0.1,µV
Ch51=2_PO10,,0.1,µV
Ch52=2_P8,,0.1,µV
Ch53=2_P4,,0.1,µV
Ch54=2_CP4,,0.1,µV
Ch55=2_TP10,,0.1,µV
Ch56=2_T8,,0.1,µV
Ch57=2_C4,,0.1,µV
Ch58=2_FT8,,0.1,µV
Ch59=2_FC4,,0.1,µV
Ch60=2_F4,,0.1,µV
Ch61=2_F8,,0.1,µV
Ch62=2_F10,,0.1,µV
Ch63=2_VEOG1,,0.1,µV
Ch64=2_VEOG2,,0.1,µV

Do you have any ideas how can I marge my data to get this format?
Thank you very much for your time.

Kind regards,
Niloofar

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Niloofar Goharbakhsh

PhD student in Developmental and Educational Psychology,
University of Bremen, Germany