Matlab files in this directory:

vb_actfile_combine_key	Combine activities and register into activity file (.act.mat)
vb_megfile_remove_environmental_noise	Remove environmental noise by using temporal PCA of reference sensor signal
vb_megfile_remove_noisysensor	Remove sensors that is possibly broken.
vb_megfile_remove_noisytrial	Remove trials that is contaminated by noise.
vb_megfile_remove_offset	Remove offset of signal by subtracting the mean signal amplitude
vb_megfile_remove_trial	Remove trials specified by ix_trial_remove from MEG data
vb_megfile_remove_trial_ext	Remove trials based on external signals
vb_megfile_write_pretrigger	Overwrite pretrigger of MEG data