All MRS studies were performed on a 1.5T MR system (Signa LX, GE Healthcare, Milwaukee, WI), and were acquired as part of clinically indicated MR examinations. All spectra were acquired using a single-voxel point resolved spectroscopy (PRESS) sequence with a short echo time of 35 milliseconds, a repetition time of 1.5 seconds, 128 signal averages, and a total acquisition time for each spectrum of approximately five minutes, including scanner adjustments. The sizes of the ROIs were typically 3 cm3 and a custom-designed newborn head coil was used to ensure an optimal signal-to-noise ratio. Processing was performed with commercially available LCModel software (Stephen Provencher Inc., Oakville, Ontario, Canada, LCModel Version 6.1-4F) and was fully automated. Concentrations of NAA, Cr, Cho, myo-Inositol (mIns), Glu, and taurine (Tau) were determined. Metabolite concentrations were corrected for varying fractions of cerebrospinal fluid in the selected ROIs [8] . For absolute quantitation, the unsuppressed water signal was used as a concentration reference [37] (link)–[43] (link) as illustrated in Fig. S2.
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