function list_properties = component_properties(EEG,blink_chans,lpf_band) % Copyright (C) 2010 Hugh Nolan, Robert Whelan and Richard Reilly, Trinity College Dublin, % Ireland % nolanhu@tcd.ie, robert.whelan@tcd.ie % % This program is free software; you can redistribute it and/or modify % it under the terms of the GNU General Public License as published by % the Free Software Foundation; either version 2 of the License, or % (at your option) any later version. % % This program is distributed in the hope that it will be useful, % but WITHOUT ANY WARRANTY; without even the implied warranty of % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the % GNU General Public License for more details. % % You should have received a copy of the GNU General Public License % along with this program; if not, write to the Free Software % Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA list_properties = []; % if isempty(EEG.icaweights) fprintf('No ICA data.\n'); return; end if ~exist('lpf_band','var') || length(lpf_band)~=2 || ~any(lpf_band) ignore_lpf=1; else ignore_lpf=0; end delete_activations_after=0; if ~isfield(EEG,'icaact') || isempty(EEG.icaact) delete_activations_after=1; EEG.icaact = eeg_getica(EEG); end for u = 1:size(EEG.icaact,1) [spectra(u,:) freqs] = pwelch(EEG.icaact(u,:),[],[],(EEG.srate),EEG.srate); end list_properties = zeros(size(EEG.icaact,1),5); %This 5 corresponds to number of measurements made. for u=1:size(EEG.icaact,1) measure = 1; % TEMPORAL PROPERTIES % 1 Median gradient value, for high frequency stuff list_properties(u,measure) = median(diff(EEG.icaact(u,:))); measure = measure + 1; % 2 Mean slope around the LPF band (spectral) if ignore_lpf list_properties(u,measure) = 0; else list_properties(u,measure) = mean(diff(10*log10(spectra(u,find(freqs>=lpf_band(1),1):find(freqs<=lpf_band(2),1,'last'))))); end measure = measure + 1; % SPATIAL PROPERTIES % 3 Kurtosis of spatial map (if v peaky, i.e. one or two points high % and everywhere else low, then it's probably noise on a single % channel) list_properties(u,measure) = kurt(EEG.icawinv(:,u)); measure = measure + 1; % OTHER PROPERTIES % 4 Hurst exponent list_properties(u,measure) = hurst_exponent(EEG.icaact(u,:)); measure = measure + 1; % 10 Eyeblink correlations if (exist('blink_chans','var') && ~isempty(blink_chans)) for v = 1:length(blink_chans) if ~(max(EEG.data(blink_chans(v),:))==0 && min(EEG.data(blink_chans(v),:))==0); f = corrcoef(EEG.icaact(u,:),EEG.data(blink_chans(v),:)); x(v) = abs(f(1,2)); else x(v) = v; end end list_properties(u,measure) = max(x); measure = measure + 1; end end for u = 1:size(list_properties,2) list_properties(isnan(list_properties(:,u)),u)=nanmean(list_properties(:,u)); list_properties(:,u) = list_properties(:,u) - median(list_properties(:,u)); end if delete_activations_after EEG.icaact=[]; end