Harmonic decomposition is FFT on the spatial domain
202211221639
Status:
Tags: functional harmonics fMRI
Harmonic functions, if defined on a circle, are sines and cosines (projection onto spatial dimension)
We expand the fast Fourier transform onto the structure of the brain → FFT is time vs. space (temporal into sinusoidals)
whereas harmonic decomposition → for each timepoint, decompose brain activity into brain states → matrix of Frequency x Time