Identification of Alzheimer’s Disease Progression Stages Using Topological Measures of Resting-State Functional Connectivity Networks: A Comparative Study

Figure 1

Flowchart for topological analyses of rs-FC networks. (a) T1-weighted MRI images were used to extract the tissues of gray matter, white matter, and cerebrospinal fluid. (b) Gray matter was coregistered into MNI space. (c) Original fMRI images were smoothed and coregistered into (d) MNI space. (e) Whole-brain parcellation atlas in MNI space was used to parcellate whole-brain into 132 parcels (Table 2), including cerebrum and cerebellum. (f) ROI-specific time serial was obtained by averaging BOLD signal timeseries within ROI voxels. (g) FC adjacent matrix computed with Pearson correlation. (h) FC adjacent matrix estimated with DTW. (i–m) Five ICA components extracted with GIG-ICA.