Fig. 3.

Comparisons across disease phases.

VBM sub-group analyses of patients in disease Phases I (rD50 < 0.25, n = 34) and II (rD50 = 0.25–0.5, n = 48) at the time of MRI acquisition. (A) In Phase I GM density decreases were observed for inferior-frontal and temporal areas in contrast to healthy controls. (B) The Phase II patients showed an extended pattern of GM and WM atrophy as compared to healthy controls. (C) The direct comparison of both phases indicated that pathology spreads beyond the motor system, including frontal, temporal and occipital GM areas. The WM density decreases were even more extensive and emphasized in subparietal projections. (TFCE; FWE corrected p < 0.001; nuisance co-variates: age, gender, total intracranial volume, onset-type, D50)

Abbreviations: GM: Gray Matter; MRI: Magnetic Resonance Imaging; TFCE: Threshold-Free Cluster Enhancement; FWE: Family-Wise Error; VBM: Voxel-Based Morphometry; WM; White Matter.