Data were acquired with two synchronized three Tesla Siemens Tim TRIO scanners, where one scanner was triggered by the other one. Twelve-channel head coils were used. A T2* gradient echo-planar imaging sequence was applied with the following parameters: 28 axial slices, with transversal orientation, oriented first to anterior commissure/posterior commissure line and then flipped by −25°, a slice thickness of 4 mm, a gap of 1 mm, a field of view of 192 mm and a voxel size of 3 × 3 × 4 mm3. The repetition time was 1.55 s with the sampling delay of 10 ms and 1.54 s. The echo time was 30 ms, and the flip angle was 73°. Slices were acquired in descending order, with the A/P phase encoding direction. The Generalized Autocalibrating Partial Parallel Acquisition method with an acceleration factor of 2 was used. A total of 327 (triggering)/324 (triggered scanner) scans were collected per condition. The first seven (triggering)/four (triggered scanner) scans were discarded during conversion of Digital Imaging and Communications in Medicine files into 4d niftis by MRIConvert (version. 2.0 rev. 216) to account for saturation effects, resulting in 320 scans available for analysis per condition.
A high-resolution (voxel size 1 × 1 × 1 mm) T1 anatomical scan was acquired for individual anatomical registration purposes.