Multiple regression analysis applied to EEG and MEG data

These tools apply multiple linear regression to EEG and MEG data, in contrast to conventional factorial averaging. The input are Neuroscan cnt-files (EEG) or Neuromag fiff-files (MEG), respectively. The output are either ascii, avg (EEG) or fiff-files (MEG), which can be processes just as conventional ERP/ERFs, e.g. with respect to source analysis. These tools are still under development. If you would like more information, please contact olaf.hauk@mrc-cbu.cam.ac.uk . A different approach to regression analysis is also part of SPM5.

In order to run your analysis, you will end up with a script like the following:

% The parameters following ### are defined once for all input files:

+ #param_file /whateverthepath/param_file.txt % file that defines predictor variables for each trigger value

+ #correl_columns 3 4 5 6 7 8 % specifies which columns in param_file contain the predictor variables

+ #trigger_columns 2 % specifies which column in param_file.txt contains trigger value (can be more than 1 column)

+ #info_file /whateverthepath/info_file.txt % output file for number of valid trials per input file

+ #mag_thresholds 2500 0 1500 0 % tresholds for artefact rejection, magnetometers (fT)

+ #grad_thresholds 1000 0 800 0 % tresholds for artefact rejection, gradiometers (fT/cm)

+ #eog_channels 307 308 % channel number of EOG channels

+ #thresholds 150 0 100 0 % tresholds for artefact rejection, EOG (uV)

+ #baseline -100 0 % interval for baseline correction with respect to trigger onset

+ #epoch_length 500 % length of epoch to be analysed

+ #pre_stim_time -100 % start latency of epoch (can be different from baseline)

% The following commands are specified for individual input files:

#fif /whateverthepath/MEG_infile.fif % input fiff-file + #outfif /whateverthepath/MEG_outfile.fif % base for output fiff-file (there will be different files for different regressors) + #fiff_template /whateverthepath/MEG_template.fif % will be used for head coordinates

#fif /whateverthepath/MEG_infile2.fif % input fiff-file + #outfif /whateverthepath/MEG_outfile2.fif % base for output fiff-file (there will be different files for different regressors) + #fiff_template /whateverthepath/MEG_template2.fif % will be used for head coordinates

• You can also run regression analysis across multiple files, e.g. several blocks for the same subject. You can also provide an external list of trigger values.