Imported at 00:00, 15 March 2026

2026-03-15T00:00:00Z

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== A sample script for ERP plots ==

We assume that we are in the data folder.

clear; close all;

DataDir=sprintf(['./']);
nCH=numel(dir([DataDir 'ECoG_ch*']));
n=whos('-file',[DataDir 'ECoG_ch1.mat'],'-regexp','ECoGData_ch1');
ECoG=zeros(nCH,n.size(2));

% load data
load([DataDir 'repEvent']);
for ch=1:nCH
openfile=sprintf('ECoG_ch%d',ch);
ECoG(ch,:)=struct2array(load([DataDir openfile]));
end
ECoG=0.25*ECoG;

% CMR (Common Median Reference)
mECoG=ECoG-ones(nCH,1)*median(ECoG);

% bandpass filter with digital filter
Fs=1000;
N=100;
Wn=[1 30]/(Fs/2);
fil=fir1(N,Wn,'bandpass');
meth='FIR digital filter';
fdmdata=filtfilt(fil,1,mECoG')';

% align on the stimulus onsets
rtime=(-1100:1000);
for t=1:length(repEvent)
fdmrpt(:,t,:)=fdmdata(:,repEvent(t,6)+503*repEvent(t,5)+rtime);
end

% plot standard and deviant ERPs
figure
for ch=1:nCH
subplot(6,6,ch-36*(ceil(ch/36)-1));

% trial rejection
data=squeeze(fdmrpt(ch,:,:));
[I K]=find(std(data,[],2)>(mean(std(data,[],2))+3*std(std(data,[],2))));
trial=[1:size(data,1)]; trial(I)=[];
data=data(trial,:);

% cut data
STD=data(:,rtime>=-603 & rtime<=-3);
DEV=data(:,rtime>=-100 & rtime<=500);

% base line correction
STD=STD-mean(mean(STD(:,1:100)));
DEV=DEV-mean(mean(DEV(:,1:100)));

plot(-100:500,mean(STD),'b'); hold on
plot(-100:500,mean(DEV),'g');
plot([0 0],[-15 15],'k'); hold off
set(gca,'XLim',[-100 500],'YLim',[-15 15],'YDir','reverse')
ylabel(['ch' num2str(ch)])
end

[[File:Demo.jpg|600px]]

Fixation Details - Revision history

Imported at 00:00, 15 March 2026