Dear SPMers,

I am trying to use the 'Prepare' function in the MEEG part of SPM to load EEG sensors.

I have converted the data from EEGLAB format using the spm_eeg_convert function. The EEGLAB analysis used version eeglab11_0_4_3b and I am using SPM8 from MATLAB R2008b on a Windows pc.

When I try to 'Assign default' sensors, I get the following error:

??? Reference to non-existent field 'pnt'.

Error in ==> spm_eeg_prep at 269
                sens.pnt = sens.pnt(sel2, :);

Error in ==> spm_eeg_prep_ui>LoadEEGSensTemplateCB at 370
D = spm_eeg_prep(S);

Error in ==> spm_eeg_prep_ui at 16
eval(callback);
 
??? Error while evaluating uimenu Callback

I have also tried using the 'Convert location file' option to select the 'ext1020.sfp' file manually, but this produces the following error:

??? Improper null index in null matrix.

Error in ==> spm_eeg_prep at 175
                elec.pnt(hspind, :) = [];

Error in ==> spm_eeg_prep_ui>LoadEEGSensCB at 427
D      = spm_eeg_prep(S);

Error in ==> spm_eeg_prep_ui at 16
eval(callback);
 
??? Error while evaluating uimenu Callback

The data contains 64 electrodes and the positions are specified as 64 x 3 double in the D.fiducials.fid.pnt field. The labels are specified in D.fiducials.fid.label. However, D.fiducials.pnt is empty -- I am unsure whether or not this is relevant.

I am eventually hoping to use the data for source reconstruction. Any help is much appreciated.

Thanks,

Emma