Detecting Cortical Activities from fMRI Data Using Delay MUSIC

摘要

The delay MUSIC (DMUSIC) algorithm is based on the delay correlation matrix of the measured fMRI signal y(t) which is defined as R(β) = < y(t) y~T (t + β) >, where β is the delay time. The objective function of the delay MUSIC is J(i) = 1./λ_(min) {A_i~T GG~T A_i, A_i~T A_i}, where G is the signal subspace derived from the correlation matrix, A_i is the transfer matrix of a head model. According to the distribution of J(i), we find the location of the sources by choosing maximus values as the locations of the active regions. An example is shown in Fig. 1