Two ways to go! The first one is to use REST. Pressing REST's Functional connectivity button, you will see a GUI pops up, click "Power spectrum" in the bottom right corner, add one EPI image of a subject (make sure the functional images have been normalized, and converted into multiple 3D hdr/img pairs first), then you will see the time course at any voxel you choose, also you will see the power spectrum of it.
The another way is to utilize REST's function and make a simple Matlab script. The main procedures are: 1. Get a ROI averaged time course by using REST --> Extract ROI signals; 2. use "fft" to calculate power spectrum. The example script is like this (should be modified before apply to your data).
Submitted by ZHANG_RESTadmin on Sun, 12/07/2014 - 14:06 Permalink
Re: average power spectrum of a roi
Two ways to go! The first one is to use REST. Pressing REST's Functional connectivity button, you will see a GUI pops up, click "Power spectrum" in the bottom right corner, add one EPI image of a subject (make sure the functional images have been normalized, and converted into multiple 3D hdr/img pairs first), then you will see the time course at any voxel you choose, also you will see the power spectrum of it.
The another way is to utilize REST's function and make a simple Matlab script. The main procedures are: 1. Get a ROI averaged time course by using REST --> Extract ROI signals; 2. use "fft" to calculate power spectrum. The example script is like this (should be modified before apply to your data).
theFreqSeries =fft(theTimeCourseNoTrend, thePaddedLen);
theFreqSeries =abs(theFreqSeries([theXLim(1):theXLim(2)]));
theFreqSeries(1:end) =theFreqSeries(1:end).^2 /length(theTimeCourse);
theFreqSeries(1:end-1) =theFreqSeries(1:end-1) *2;
plot(theFreqLim, theFreqSeries, 'Color', 'blue');