12 channel radiofrequency head coil

MRI and 1H-MRS data were collected on a Siemens 3-Tesla TrioTIM scanner using a 12-channel radiofrequency head coil. T1-weighted images were collected in the sagittal plane using a five-echo 3D MPRAGE sequence (TR/TE/TI = 2530/1.64, 3.5, 5.36, 7.22,9.08/1200 ms, flip angle = 7°, field of view = 256 × 256 mm, matrix = 256 × 256, 1 mm thick slice, 192 slices, GRAPPA acceleration factor = 2). Using these images, a single 1H-MRS voxel was positioned in the bilateral medial frontal cortex directly superior to the corpus callosum, containing anterior cingulate, middle frontal, and superior frontal gyri (see Fig. 1; [3 (link)]. A PRESS (point-resolved spectroscopy) sequence (TR/TE = 1.5 s/40 ms, voxel size = 20 × 30 × 20 mm, averages = 192) was collected, using an echo time (TE) of 40 ms for improved detection of Glu [12 ]. An unsuppressed water sequence for use as a concentration reference and eddy current correction in post-processing was collected with 16 averages and otherwise identical parameters for each spectrum. Figure 1 depicts the voxel location in a single MRI.

Brain imaging data was acquired with a 3T Siemens Trio scanner and a 12-channel radiofrequency head coil at the Human Neuroimaging Laboratory of Baylor College of Medicine in Houston, Texas. A Magnetization Prepared Rapid Gradient Echo (MPRAGE) sequence was used to acquire 3D anatomical images with a T1-weighted contrast. We used a TR of 1200 ms, an in-plane resolution of 1 mm × 1 mm, and a slice thickness of 1 mm with a field of view (FoV) of 87.5% (matrix of 256 × 256). Anatomical images were acquired in ascending sequential order in the axial plane. An Echo Planar Imaging (EPI) sequence was used to acquire functional data. We used a TR of 3000 ms, a TR delay of 1420 ms for the scanner silent interval, a 90 degree flip angle, and a voxel size of 3.4 × 3.4 × 5 mm. Twenty-six slices per volume were acquired in an interleaved descending order in the axial plane. To optimize the timing synchronization between the task and the scanner, we used in-house NEMO software (Network Experiment Management Objects)