Figure 1.

Illustration of the feature extraction in FuSeISC for one arbitrary voxel located at coordinate (x,y,z). At first, M ISC matrices are independently computed based on the fMRI time series of N subjects. In our study, the total number of time series was M = 5, corresponding to the total number of tasks (ICBM data) or movie clips (StudyForrest data) of interest. From each N × N ISC matrix, mean and variability are extracted using the Jackknife procedure. These two features are stacked into a single feature vector f_xyz, whose dimension is 2M. This procedure is repeated for each brain voxel to obtain altogether 228,483 and 449,612 feature vectors for cluster analysis, corresponding to the ICBM and StudyForrest data, respectively. [Color figure can be viewed at http://wileyonlinelibrary.com]