fMRI data acquisition
fatigue
A 3T Siemens (Erlangen, Germany) MAGNETOM Skyra scanner was used for neuroimaging data acquisition. T1-weighted anatomical images (256 × 256 mm matrix; 1 mm isotropic voxels) were acquired using a Magnetization Prepared Rapid Gradient Echo (MPRAGE) sequence (TR: 2100 ms; TE: 3.43 ms). Thirty-four echo-planar, functional slices were obtained in an interleaved order with the following parameters: 3 mm isotropic voxels, interslice gap: 0.3 mm, TR: 2000 ms, TE: 30 ms, field of view: 204 mm × 204 mm, flip angle: 90°. Functional images were acquired at a transversal orientation to the anterior commissure – posterior commissure (AC-PC) axis. Approximately 255 volumes were acquired during each functional run. VAS-F state fatigue ratings made throughout the task were self-paced, which contributed to slightly different numbers of volumes across runs.