Mr750w scanner

MRIs were performed using a 3 Tesla General Electric (GE) MR750w scanner (GE Healthcare, Waukesha, WI) with a 32-channel head coil at the Alberta Children’ Hospital Research Imaging Suite. High-resolution T1-weighted fast spoiled gradient echo brain volume (FSPGR BRAVO) anatomical images were obtained in the axial plane [voxels = 1 mm isotropic, no skip, 166–225 slices, repetition time (TR)/echo time (TE)/inversion time (TI) = 8.5/3.2/600 ms, flip angle = 11°, duration ~ 5:00]. Diffusion-weighted images were also obtained axially for 32 non-collinear directions (voxels = 2.5 mm isotropic, 60 slices, b-value = 750 s/mm², 3 b = 0 volumes, TR/TE = 11.5 s/69 ms, duration ~ 6:00). Resting-state functional MRI images were obtained while participants fixated on a centrally presented black cross and were told to think of “nothing in particular” (voxels = 3.6 mm isotropic, 36 axial slices, 150 volumes, TR/TE = 2000/30 ms, flip angle = 90°, duration ~ 5:00).

Both whole-brain functional and T1-weighted MRI scans were carried out on a 3.0T GE MR750W scanner (GE Healthcare) with a standard head coil. Each participant was instructed to stay awake with eyes closed and relax their minds until the examination was over (28 (link), 29 (link)). The whole-brain anatomical T1-weighted images were collected with a three-dimensional spoiled gradient-recalled echo sequence with following parameters: repetition time (TR)/echo time (TE), 8.5 ms/3.3 ms; gap, 0 mm; field of view (FOV), 240 × 240 mm²; acquisition matrix, 256 × 256; thickness, 1.0 mm; and flip angle, 12°.
The whole-brain fMRI data was recorded by applying gradient-recalled echo-planar imaging sequence with parameters as follows: TR/TE, 2,000 ms/25 ms; gap, 1.2 mm, thickness, 3.0 mm; FOV, 240 × 240 mm²; acquisition matrix, 64 × 64; 35 axial slices; and flip angle, 90°. The whole scanning time was ~15 min, and a total of 240 volumes of functional images were acquired.