Image acquisition, pre-processing and calculation of DTI indices are provided in detail in (Bava et al., 2009). Briefly, participants were imaged in a 3T General Electric Excite MR system with an 8-channel phase-array head coil (General Electric Medical System, Milwaukee, WI, USA). Diffusion-weighted images were generated with a single-shot dual spin echo excitation and collected along 15 non-collinear directions in addition to a reference image with no diffusion weighting (b=0). The following sequence parameters were applied and averaged over four volumes: TE/TR=93/12,000 ms, FOV=240 mm, matrix =128×128, 36 contiguous slices, 3 mm slice thickness, b-value=2000 s/mm2. Two field maps were collected (TE/TR=3.8/1,000 ms) to correct for signal loss and geometric distortion due to B0 field inhomogeneities (Andersson & Skare, 2002; Jezzard & Balaban, 1995).
