fMRI_data

Data were acquired at the Stanford University Richard M. Lucas Center for Imaging on a 3T General Electric SIGNA Premier scanner using a 48-channel head coil (GE Healthcare, Milwaukee, WI, USA). Blood oxygenation level-dependent (BOLD) functional MRI data were acquired using a simultaneous multislice gradient-echo echo-planar pulse sequence. Sequence parameters were similar to those used as part of the Human Connectome Project: TR 1000 ms, TE 30 ms, flip angle 64°, 2.4 mm isotropic voxels, matrix 88 × 88 × 65, multi-slice 5× acceleration. Minimization of signal dropout was achieved by visually selecting a slice plane approximately 25° from the anterior-posterior commissural plane towards the coronal plane. A T1-weighted anatomical scan was acquired in each session using a 3DFSPGR three-dimensional sequence: TR 1891 ms, TE 1.172 ms, TI 400 ms, flip angle 11°, 1.0 × 1.0 × 1.2 mm voxels, matrix 256 × 192 × 132. A gradient-echo B0 fieldmap was acquired to correct for spatial distortions: TE 6.5, 8.5 ms with slice prescription/spatial resolution matched to the BOLD sequence.Data collected during a visual fixation task were used for functional connectivity analysis. The patient fixated a black ‘+’ symbol presented at the center of a light gray screen. The patient was asked to remain as still as possible, and to remain awake and focused throughout the duration of each run. In between runs, the patient was asked if he was able to successfully stay still during the previous run, to reinforce the expectation that this should be closely monitored. Each run lasted 7m 2s and three functional runs were collected.