Functional echo-planar datasets sensitive to BOLD (Blood Oxygen Level Dependent) contrast were acquired at 1.5 Tesla (Siemens Sonata) The sequence, minimizing orbitofrontal signal dropout [55] achieved partial brain coverage (28 slices, 2 mm slice thickness, 1 mm gap, tilted −30° from inter-commissural plane, TR 2.52 seconds per volume, TE 40ms [see figure one]).
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C) Functional MR echo planar images will be acquired while participant complete an established working memory task (n-back); TR=2400ms, 3.3 mm isotropic voxels.
After each syllable sequence, functional gradient-echo planar images (EPI) were acquired (sparse imaging [38, 39]) on a 3 Tesla-scanner (Siemens Allegra, Erlangen, Germany; 42 slices; −5 degree tilt; slice thickness 2 mm, interslice distance 1 mm; cardiac triggering).
We acquired 289 functional T2*-echo planar images (EPI; field-of-view 192 mm, slice thickness 3.5 mm, slice spacing 0.2 mm, repetition time 1850 ms, echo time 26 ms, flip angle 75°, 36 slices, ascending slice acquisition order, whole brain coverage) in each session.
The imaging session consisted of the acquisition of a T1-weighted high-resolution anatomical image (MPRAGE, 176 sagittal slices, voxel size: 1×1×1 mm), followed by the acquisition of a single series of functional images (gradient-echo echo-planar, 520 scans, 35 axial slices, voxel size: 3×3×3 mm, TR = 2.35 s, TE = 30).
For each functional run, an echo planar gradient-echo imaging sequence sensitive to BOLD contrast was used to acquire 33 slices per repetition time (TR) (3 mm thickness), with a TR of 2000 ms, echo time of 30 ms, flip angle of 90 degrees, field of view of 192 mm, and 64×64 matrix.
For functional imaging, an echo planar imaging (EPI) sequence was used (repetition time = 3,000 ms, echo time TE = 50 ms, flip angle 90°, field of view = 192, 30 axial slices, 64 × 64 in-plane matrix, and 5 mm slice thickness).
For functional MRI, an echo planar imaging sequence (flip angle 80°; repetition time = 2300 ms; echo time = 30 ms, matrix, 96 × 96 pixels; field of view 220 × 220 mm) was used, covering the whole brain (40 axial slices; 2.29 mm × 2.29 mm in-plane resolution; 3.0 mm slice thickness).
For functional scans, a Gradient Echo (GE) echo planar imaging (EPI) sequence with TE/TR = 30/2500 was performed, with seventy-four volumes acquired.
