Whole-brain blood oxygenation level dependent (BOLD) imaging was conducted on a Siemens 3T Magnetom Trio scanner across three functional scans. A whole-brain high resolution anatomical image volume (1.0mm × 1.0mm × 1.2mm voxel dimension) was first collected using a 3D magnetization prepared rapid gradient echo (MPRAGE) sequence for anatomic registration of the functional images. In three functional runs, blood oxygenation level dependent images of 37 slices covering a 111mm superior-inferior extent of the brain were acquired over a 402s period, using a gradient echo echo-planar imaging sequence that incorporated a 3D prospective acquisition correction (acquisition matrix = 96 × 96, voxel size = 2.5mm × 2.5mm × 3.0mm; For 12 subjects (7 HD-FHP, 5 HD-FHN): 134 measurements, TR/TE = 3000/40ms, flip angle = 90°, no acceleration, slice thickness = 2.5mm with 0.5mm interslice gap; For 14 subjects (7 HD-FHP, 7 HD-FHN): 174 measurements, TR/TE = 2250/30ms, flip angle = 78°, GRAPPA acceleration factor = 2, slice thickness = 3.0mm with no inter-slice gap These minor acquisition differences, which were balanced across groups, were necessary given an upgrade to the Trio.
