[FieldTrip] timelockanalysis and beamformer

[Tyler Grummett]

?Hello fieldtrip,


I was just wondering when it is appropriate to use the configuration cfg.keeptrials = 'yes' in ft_timelockanalysis, and when it is appropriate to have it as 'no'.


I have continuous data of 30 seconds. However its separated into a 5, 6 and 19 second segments. So they arent event-related events.


At present I am not asking timelockanalysis to keep the trials, or ft_sourceanalysis  (LCMV beamformer) for that matter. Is this bad? Im worried about unstable spatial filters (if I calculate covariance matrices and spatial filters for each trial) and loss of phase (if I average the covariance matrices over trials and produce one spatial filter).


I noticed that in the tutorial connectivityextended that they never specify these things and therefore use the default, which is cfg.keeptrials = 'no' and they calculate . Is that my answer?


Tyler


*************************

Tyler Grummett ( BBSc, BSc(Hons I))
PhD Candidate
Brain Signals Laboratory
Flinders University
Rm 5A301
Ext 66125
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