Hi Francois,
Thanks for your reply.
The SSP that I posted earlier, blinks & saccades though had same pattern had different component weights. I have always used ''use existing SSP projectors''
Here are the SSPs remarked:
Blinks 11%
Cardiac 9%
Saccadic 8%
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Sorry if I didn't make it clear at the start, but it is an eye open experiment.
Since it was the first run testing the entire setup, I didn't have a fixation cross. But yes, I have added that now with additional electrodes for future measurements. -
I have processed the dataset in both continuous and epoched files.
With _AUX.ds (previous screenshots) and *.ds today.
Here is what I have done so far:
Linked the epoched (*.ds) file, marked the events.
Computed the SSPs, blinks first, saccades later. Imported the recording as standard & deviant.
Computed FFT for both and marked the bad channels. Removed the power line contamination. Based on those, got the averages, which do look a lot cleaner.
FFT:
Averages: deviant & standard
Got the dSPM for both the conditions.
The localisation has slightly improved, in terms that it at least is now showing us activation in some what reasonable location. However, the eye related artefacts are still present. Interestingly, the activation seems to have 'lateralised' to the left side hemisphere.
Standard average
Deviant average
Lastly, the way I understand the procedure of generating dSPM is that we compute it for every trial and average it in the source space before displaying (induced responses?).
So is there a way to construct sources directly for the cleaner averaged waveform? This wont be as accurate as the method described in the tutorial but wont it get rid off the eye artefacts as those wont be time locked?
Thanks,
Kanad