腦電EEG靜息態求頻域各指標

關於靜息態求頻域的腳本

%
% Written By Yizhou
% resting or praying
% Using the code without proper understanding the code and relevant background
% of EEG may lead to confusion, incorrect data analyses,or misinterpretations
% of results.
% The author assumes NO responsibility for inappropriate or incorrect use
% of this code.
% WX：         17373158786

%

%頻域分析設置
% Fs採樣率
Fs = 512;
%分段長度 256*2
L = 1024;
%T = 1/Fs;
%t = (0:L-1) * T;
NFFT = 2^nextpow2(L);
%創建頻域列表
f = Fs/2 * linspace(0,1,NFFT/2+1);



% 路徑設置爲預處理的文件夾
anal_path = 'E:\Docu\Work\1_Projects\Rest_8\anal_V2\resting';cd(anal_path);
files = dir([anal_path,filesep,'R_ICA*resting.set']);

if ~exist([anal_path,filesep,'fft_result'],'dir')
    mkdir([anal_path,filesep,'fft_result']);
end
fre_path = [anal_path,filesep,'fft_result'];%%% 頻域結果儲存路徑
cd(fre_path);


for sub_No = 1:length(files)
    setname = files(sub_No).name;
    EEG = pop_loadset([anal_path, filesep, setname]);
    %對於所有通道
    for ii=1:size(EEG.data,1)
        %對於所有分段
        for jj=1:size(EEG.data,3)
            %提取第ii個通道 第jj個分段 所有時間點數據
            y = squeeze(EEG.data(ii,:,jj));
            %做FFT變換 求真實幅值----------------------------------指標1：幅值
            temp = fft(y,NFFT)/ L;
            fuzhi(jj,:) = 2*abs(temp(1:NFFT/2+1));
            % 做FFT變換，求功率（uV平方）%-------------------------指標2：功率
            temp = fft(y,NFFT)/L;
            power(jj,:)=(2*abs(temp(1:NFFT/2+1))).^2; % fft results, in power
            % 做FFT變換，求功率譜密度（PSD）（單位 uV平方/ Hz）%----指標3：功率譜密度
            temp = 2*abs(fft(y,NFFT)).^2/L/Fs;
            PSD(jj,:) = temp(1:NFFT/2 + 1);
            % 做FFT變換，求功率譜密度（PSD）（單位 dB ）%----------指標4：功率譜密度
            temp = 2*abs(fft(y,NFFT)).^2/L/Fs;
            DB_PSD(jj,:) = 10*log10(temp(1:NFFT/2+1));
            
        end
        %數據彙總：被試*通道*頻率
        
        
        mean_fuzhi(sub_No ,ii,:) = squeeze(mean(fuzhi,1)); clear fuzhi;
        mean_power(sub_No ,ii,:) = squeeze(mean(power,1)); clear power;
        mean_PSD(sub_No ,ii,:) = squeeze(mean(PSD,1)); clear PSD;
        mean_DB_PSD(sub_No ,ii,:) = squeeze(mean(DB_PSD,1)); clear DB_PSD;
        
    end
    % 保存各個指標
    
end

% 保存結果文件到當前路徑，代碼中爲fft_results;
save ('fuzhi.mat', 'mean_fuzhi');
save ('power.mat', 'mean_power');
save ('PSD.mat', 'mean_PSD');
save ('DB_PSD.mat', 'mean_DB_PSD');
% %             clear mean*;