Standard 12 channel head coil

Functional MRI data were collected at Mara Hospital, Bethel Epilepsy Center, using a 3T Siemens Verio scanner with a quantum gradient and a standard 12-channel head coil (Siemens, Erlangen, Germany). Functional images were acquired using a single T2-weighted gradient echo planar imaging sequence with the following parameters: slice thickness 4 mm (1 mm gap), repetition time (TR) 2,100 ms, echo time (TE) 30 ms, flip angle 90^°, field of view (FOV) 192 × 192 mm, matrix size 64 × 64, voxel size 3 × 3 × 4 mm. The number of volumes was 377, each containing 30 axial slices covering the whole brain and measured in descending order parallel to the hippocampus. Using the software Presentation^® (Neurobehavioral Systems Inc., Berkeley, CA, USA), visual stimuli were displayed on a screen inside the MRI scanner, which the participants saw through a mirror attached to the head coil. Before the EPI sequence, field map sequences were applied to control for magnetic field inhomogeneities. In addition, high-resolution anatomical images were acquired using a T1-weighted, 3-dimensional magnetization-prepared rapid gradient echo sequence (slice thickness 0.8 mm, TR 1,900 ms, TE 2.5 ms, inversion time 900 ms, flip angle 9^°, FOV 240 × 240 mm, matrix size 320 × 320, voxel size 075 × 0.75 × 0.75 mm, 192 slices).

Functional and structural images were acquired with a 1.5-Tesla Siemens Symphony whole-body scanner (Siemens, Erlangen, Germany) with a quantum gradient system and a standard 12-channel head coil (Siemens, Erlangen, Germany). Functional images were obtained using a single shot T2*-weighted gradient-echo planar imaging (EPI) sequence. The number of volumes was 210, each containing 30 transversal slices covering the whole brain and measured in descending order parallel to the AC-PC line (slice thickness = 4 mm; 1 mm gap; TR = 3000 ms; TE = 59 ms; flip angle = 90°; field of view = 192 × 192 mm²; matrix size = 64 × 64; voxel size = 3 × 3 × 4 mm³). During scanning, participants lay comfortably in a supine position in the MR scanner. An adjustable head holder restricted head movements. Visual stimuli were displayed on a back-projection screen (1280 × 1024 pixels) near the tube end. Subjects watched the screen via a dual-mirror which was mounted to the head coil. The angle of vision was approximately 11 degrees vertically and 18 degrees horizontally. Before the beginning of the experiment, high-resolution anatomical images were acquired using a T1-weighted, three-dimensional Magnetization Prepared Rapid Gradient Echo (MPRage) sequence.

The MRI scans were performed at the Imaging Center for Brain Research, Beijing Normal University using a Siemens Trio 3-T scanner with a standard 12-channel head coil (Siemens, Erlangen, Germany). A standard radiofrequency head coil was used with foam padding to restrict head motion. A 3D T1-weighted Magnetization Prepared Rapid Gradient Echo Imaging (MPRAGE) sequence was used to acquire high-resolution anatomical scans with the following parameters: 176 sagittal slices, repetition time (TR) = 2530 ms, echo time (TE) = 3.45 ms, flip angle (FA) = 7°, slice thickness = 1 mm, acquisition matrix = 256 × 256, in-plane resolution = 1 × 1 mm². Other MRI modalities were not used in the current study and therefore were not described here.