Source localization of frequency bands

Discussions
1

Hi,

First, I would like thank you for the outstanding effort, and the amazing tutorial.
I came across this article “The applications of time-frequency analyses to ictal magnetoencephalography in neocortical epilepsy” by Yagyu ea al. PMID 20605700
In this article the authors “projected” beta/alpha bands on a 3D rendering of the MRI. Unfortunately, it was not clear in the article how this projection was done, and whether it was a simple geometric projection vs. it was based on source modeling and inverse problem solution. I understand it is not currently possible to compute the sources for frequency bands in brainstorm because the band values are average of the power values of the individual frequencies. I’m just wondering about your thoughts on how the authors were able to do it, and if it is something you can do/add to brainstorm.

Thank you

R

2

Sorry for the delay in responding:

I agree that the best way to proceed is to compute the power spectrum at each cortical location and display maps in the frequency bands of interest. As it happens, we are working actively on new features that will do exactly this and which should be released by the end of April. They will also include Hilbert transforms that will generate time-resolved maps of signal envelopes in frequency bands of interest; which relates to your question as well. So please stay tuned for major updates by looking at our What’s New page: http://neuroimage.usc.edu/brainstorm/News

Hope this helps,

3

Thanks a lot !!