<div dir="ltr"><div class="gmail_signature"><div dir="ltr"><div>Dear all,</div><div><br></div><div>I have 60 channel EEG resting state data, and after discarding bad channels, I am left with 48 channels common to all subjects. </div><div><br></div><div>I applied scalp current density to my data before extracting power information from my EEG data. The EEG cap that I used was in a 10-10 system, and I don't have the electrode position file. Hence, I used the default electrode position file named 'standard_1005.elc' for the purpose.</div><div><br></div><div>Here's the part of my script for the surface Laplacian:</div><div><br></div><div><br></div><div><div> cfg_neighb.method = 'template';</div><div> cfg_neighb.layout = 'EEG1010.lay';</div><div> cfg_neighb.channel = 'all';</div><div> cfg_neighb.feedback = 'no';</div><div> </div><div> neighbours = ft_prepare_neighbours(cfg_neighb, data7);</div><div> </div><div> cfg = [];</div><div> cfg.method = 'finite';</div><div> cfg.elecfile = 'standard_1005.elc';</div><div> cfg.elec = ft_read_sens(cfg.elecfile);</div><div> cfg.trials = 'all';</div><div> cfg.neighbours = neighbours;</div><div> cfg.conductivity = 0.33;</div><div> </div><div> data8 = ft_scalpcurrentdensity(cfg, data7);</div></div><div><br></div><div>When I tried to extract power from data8 (after surface Laplacian), I keep getting an error message (see below). I'm not sure why this would be the case, and would appreciate very much if someone could help me resolve the error!</div><div><br></div><div>Thank you!</div><div><br></div><div>Here's my script for extracting the power:</div><div><div> cfg = [];</div><div> cfg.output = 'pow';</div><div> cfg.channel = {'all'};</div><div> cfg.method = 'mtmfft';</div><div> cfg.keeptrials = 'no';</div><div> cfg.tapsmofrq = 5;</div><div> cfg.layout = 'EEG1010.lay';</div><div> </div><div> % for frequencies up to 30 Hz</div><div> cfg.foilim = [1 30]; % either the full range of frequencies (data2.hdr.Fs/2) or up to 100 Hz</div><div> cfg.taper = 'hanning';</div><div> </div><div> % find the index for the c200 condition</div><div> pre_c200_idx = find(data8.trialinfo == 200);</div><div> cfg.trials = pre_c200_idx;</div><div> LF_pre_c200 = ft_freqanalysis(cfg, data8);</div><div><br></div><div>Here's the output plus error message:</div><div><br></div><div>the input is raw data with 48 channels and 343 trials</div><div>Error using ft_datatype_sens (line 375)</div><div>inconsistent number of channels in sensor description</div><div><br></div><div>Error in ft_datatype_raw (line 138)</div><div> data.elec = ft_datatype_sens(data.elec);</div><div><br></div><div>Error in ft_checkdata (line 223)</div><div> data = ft_datatype_raw(data, 'hassampleinfo', hassampleinfo);</div><div><br></div><div>Error in ft_freqanalysis (line 209)</div><div>data = ft_checkdata(data, 'datatype', {'raw', 'raw+comp', 'mvar'}, 'feedback',</div><div>cfg.feedback, 'hassampleinfo', 'yes');</div><div> </div></div><div>Best regards,</div><div>Hweeling</div><div><br></div></div></div>
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