Dear SPM team,
We are working on trying to use SPM source reconstruction outputs for
source space traveling wave analyses (like in Murphy et al. PNAS 2009
- http://www.ncbi.nlm.nih.gov/pubmed/19164756).
Basically this analysis involves reconstructing source current density
at each time point for all mesh vertices and then track spatial
traveling of currents using streaming algorithms.
I was wondering if it is correct that whole-brain source reconstructed
time course results can be obtained using:
full_output_timecourses = J*T'
where J is SPM 12's D.other.inv{1}.inverse.J{1,:}
(the source amplitude conditional expectation) - in my example output
(5124 vertices x 16 modes)
and T is SPM 12's D.other.inv{1}.inverse.T
(the temporal projector) - in my example output (16 modes x 4001 time points)
It seems that in SPM12 spm_eeg_invert_display would use such a formula
(in line 143) for reconstructing time course of activity for a
selected single source when called from the GUI.
Would the current source density be equivalent to the absolute value
of the obtained time courses?
Thanks so much in advance for your help,
Melanie Boly
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