All MRI data were preprocessed using the software package SPM8 (Statistical Parametric Mapping 8; http://www.fil.ion.ucl.ac.uk/spm/software/spm8). The first three frames of each fMRI session were dropped to allow signal equilibrium. Then, anatomical and functional images were reoriented to the anterior commissure and coregistered to the anatomical MNI T1 template. The anatomical images were segmented and normalized to the MNI T1 template. Functional data were realigned and unwarped and spatially normalized to the MNI T1 template using the normalization parameter created by the segmentation process. Further, fMRI data were smoothed with a full width half maximum (FWHM) of the Gaussian smoothing kernel of 8 × 8 × 8 mm. The data were temporally bandpass filtered (0.01–0.1 Hz) and corrected for head motion (i.e., six head motion regressors from SPM realignment procedure), white matter and ventricular signal using the conn toolbox (http://www.nitrc.org/projects/conn).
